PH meter - XL 15 Meter: Table of Contents Introduction

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Unformatted text preview: XL 15 Meter: Table of Contents Introduction ..................................................................1 Unpacking the Meter ...........................2 XL Series Meters Specifications .............................. 3-4 Getting Started XL Series Meters Connectors .................................. 5-8 Start-up and Shut down procedures ............................9 pH and Ion probes ............................................... 11-12 Using the XL Series Meter Touch Screen Operation...................................... 15-16 Screen Contrast Adjustment ......................................16 Using The Stylus........................................................17 Stylus Calibration .......................................................17 Setting Time And Date...............................................18 On-Screen Keyboard .................................................19 Expansion Cards .......................................................20 Connecting To The Internet .......................................21 Button Functions .................................................. 22-25 Channel Assignment............................................ 26-27 Display Setup.............................................................28 pH Setup pH Setup Screen And Function Buttons ....................29 Access pH Setup .......................................................30 Set Sample ID#..........................................................31 Select Buffer Group ...................................................32 Select Buffer Recognition ..........................................33 Select Auto Read Mode ............................................33 Set Ph Stability Criteria ..............................................34 Set Default Temperature............................................34 Set Isopotential Point ................................................35 Set Alarm Limits.........................................................35 Set Print Criteria.........................................................36 Set Data Storage Criteria...........................................37 Set Display Criteria Setup..........................................38 View Stored Data ................................................. 39-40 mV Setup mv Setup Screen And Function Buttons ....................41 Access mv Setup .......................................................42 Set Sample ID#..........................................................43 Set Alarm Limits.........................................................44 Set Print Criteria Setup .............................................45 Set Data Storage Criteria...........................................46 Set Display Criteria ....................................................47 View Stored Data ................................................. 48-49 pH Operation About pH Measurement........................................... 111 Standardizing with Auto Buffer Recognition .................................. 112 Standardizing with Manual Buffer Recognition.............................. 113 Temperature Standardization .................................. 114 pH Measurement with Auto Read On And Off............................................................. 115 Graphing Function .................................................. 116 mV Operation About mv Measurement .......................................... 117 Absolute mv Measurement...................................... 118 Relative mv Standardization and Measurement...... 118 Graphing Function .................................................. 119 Warranty ................................................................. 160 Compliance ............................................................ 160 Appendix Setting the XL Series Meters User Profiles ......161-163 XL Series Meters Factory Default Settings ...................................164-166 XL Series Meters Print Function ...................................................167-168 Background and Color Adjustment...................169-170 Determining Isopotential Points Experimentally ...................................................... 171 pH Theory.........................................................172-175 Replacement Parts ...........................................185-187 68X374204 Rev 5 Jan’08 i Introduction XL15, 20, 25, 30, 40, 50 and 60 meters Thank you for selecting a Fisher Scientific accumet meter. You have one of these XL series models: ● XL15 – pH/mV/Temp meter ● XL40 - DO/BOD/OUR/SOUR meter ● XL20 - pH/mV/Temp/Conductivity meter ● XL50 - pH/mV/Temp/Ion/Conductivity meter ● XL25 - pH/mV/Temp/Ion meter ● XL60 - pH/mV/Temp/DO/Ion/Conductivity meter ● XL30 – Conductivity/ Resistivity/TDS/Salinity/Temp meter This manual describes the operation of the accumet XL series meters. For the model of your purchase, simply use the model’s Table of Content to guide you to your meter’s operating instructions. The state-of-the art meter that you have purchased runs on a Windows CE platform and has a similar framework of a pocket PC (or "Palm Pilot"). It is easy to operate and will guide you through the various functions by displaying easy to understand prompts. This operating manual should answer any questions that might arise in operating your meter; however, do not hesitate to call our accumet Technical Support Hotline at 1-888-358-4706, if you need any assistance. This meter is designed to provide all the information necessary to guide you through the measurement process with a series of prompts on the screen. The XL series meters provide microprocessor precision in a compact bench top design that is easy to use, letting you: ●Measure pH or pH (FET); absolute mV or relative mV ●Measure ion concentration ●Measure conductivity, resistivity, Total Dissolved Solids (TDS) and salinity (Applicable only for XL15, XL20, XL25, XL50, and XL60) (Applicable only XL25, XL50, and XL60) (Applicable only for XL20, XL30, XL50, and XL60) (Applicable only for, XL40 and XL60) (Applicable only for XL15, XL20, XL25, XL50, and XL60) (Applicable only for XL15, XL20, XL25, XL50, and XL60) (Applicable only for XL20, XL30, XL50, and XL60) (Applicable only for XL15, XL20, XL25, XL50, and XL60) (Applicable only for XL20, XL30, XL50, and XL60) (Applicable only for XL25, XL50, and XL60) (Applicable only for XL40, and XL60) (Applicable for XL15, XL20, XL25, XL30, XL40, XL50, and XL60) (Applicable for XL15, XL20, XL25, XL30, XL40, XL50, and XL60) (Applicable only for XL25, XL50, and XL60) (Applicable for XL15, XL20, XL25, XL30, XL40, XL50, and XL60) (Applicable for XL15, XL20, XL25, XL30, XL40, XL50, and XL60) ●Measure DO, BOD, OUR and SOUR ●Select one of three sets of standard pH buffer groups ●Standardize with up to 5 pH standard or custom buffers ●Standardize with up to 4 conductivity standards ●Implement automatic pH buffer recognition ●Implement automatic conductivity standard recognition ●Select one of six ion standardization methods ● Standardize Dissolved Oxygen with up to two standards ●Customize your display and operating parameters ●Assign operator and sample identification numbers ●Specify ion selective electrode type ●Store 1000 data points per user in the meter’s memory or transfer data to a computer or printer. ●Access extensive help with just a touch of a button It all adds up to rapid, completely automatic, intuitive operation. 1 Introduction XL15, 20, 25, 30, 40, 50 and 60 meters Unpacking the Meter The following is a listing of what you should have received with your new accumet XLseries bench top meter. Meter with kit includes: meter power supply electrode arm support bracket electrode arm manual and literature pH electrode (13-620-130) Conductivity 13-620-100, 2 cell, 1.0 cell constant ATC probe (13-620-19) BOD probe (13-620-SSP; with XL60D kit only) XL15 XL20 XL25 XL30 XL40 XL50 XL60 ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● XL30 XL40 ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● XL60 Meter only includes: meter power supply electrode arm support bracket electrode arm manual and literature XL15 XL20 XL25 XL50 ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● If any of these items are missing, please contact the accumet Technical Support Hotline at 1-888-358-4706. Accessory Conductivity Probes and Ion Selective Electrodes are available and can be ordered by calling Fisher Customer Service at 800/766-7000. Accessory pH, ISE, and Conductivity probes are available and can be ordered by calling Fisher Customer Service at 800/766-7000 . Useful tips will appear in this box throughout this manual. 2 XL Series Meters Specifications XL15, 20, 25, 30, 40, 50 and 60 meters Display screen size menu options help screens configurable display keypad controls General inputs/outputs 640x480 digit LCD 4 1/2” x 6” extensive extensive yes context specific touchscreen (Applicable for XL15, XL20, XL25, XL30, XL40, XL50, and XL60) electrical requirements output from PSU line voltage tolerance input impedance meter size meter weight Memory internal diagnostics programmable data storage programmable data output print interval programmable alarm BNC, ATC, DIN (FET)- ( XL15, XL20, XL25, XL50, and XL60) DIN (Conductivity) – (XL20, XL30, XL50, and XL60) DIN (DO) – XL40, and XL60 RS232, USB-B, USB-A, RJ45 – (Applicable for all models) 115 V/60 Hz, 230 V/50 Hz 9VDC, 3.3A center negative ± 10% >10 12 ohms 6.75"x9.25"x3.5" 2.8 lb. 1000 data pts yes store on stable, time, manual timed or logged data 3 to 86400 sec yes (Applicable for XL15, XL20, XL25, XL30, XL40, XL50, and XL60) pH Mode range resolution relative accuracy automatic buffer recognition manual buffer recognition calibration points auto lock FET -2.000 to 20.000 0.1/0.01/0.001 ± 0.1/0.01/0.002 + 1 Lsd yes yes 5 yes yes (Applicable only for XL15, XL20, XL25, XL50, and XL60) mV Mode range resolution accuracy ± 2000.0 0.1 ± 0.2 (Applicable only for XL15, XL20, XL25, XL50, and XL60) 1x10–6 to 9.99x1010 2 / 3 or 4 digits ±0.17n% 5 KA, KS, AA, AS (Applicable only for XL25, XL50 and XL60) Ion Mode range resolution relative accuracy calibration points incremental methods continued on next page 3 XL Series Meters Specifications XL15, 20, 25, 30, 40, 50 and 60 meters Conductivity Mode cell constants range conductivity resistivity 0.1, 1.0, 10 0 to 500 mS/cm over 4 ranges 0 to 200.0 µS, 200.0 µS to 2.000 mS, 2.000 to 20.00 mS, 20.00 to 500.0 mS 3 ohm-cm to 100 megohm-cm over 4 ranges 0 to 20.00 KOhms, 20.00 to 200.0 KOhms, 200.0 KOhms to 2.000 MOhms, 2.000 to 100.0 Mohms 0.0 to 500.0 ppt over 4 ranges (depending on the TDS factor) 0 to 200.0 x TDS factor ppm, 200.0 x TDS factor to 2000 x TDS factor ppm, 2.000 x TDS factor to 20.00 x TDS factor ppt, 20.00 x TDS factor to 200.0 x TDS factor ppt 0 to 90 ppt over 4 ranges 0 to 0.094 ppt, 0.094 to 1.000 ppt, 1.0 to 11.50 ppt, 11.50 to 90.00 ppt 0.5% of full scale + 1 digit (Applicable only for XL20, XL30, XL50, and XL60) Total Dissolved Solids (TDS) salinity accuracy Dissolved Oxygen Mode range resolution accuracy Temperature Mode range range resolution accuracy Barometric Pressure range resolution accuracy Salinity Correction range 0 to 60 mg/L (0 to 1272 mbar) 0 to 600 % saturation 0.01 mg/L (0.1 mbar) 0.1 % saturation 0.1 + 1 least significant digit (Applicable only for XL40 and XL60) -5.0 to +105.0 °C (for meter only) (Applicable only for XL15, XL20, XL25, XL30, XL50, and XL60) -5.0 to +46.0 °C 0.1 °C ± 0.2 °C (Applicable only for XL40 and DO mode in XL60) 450 to 825 mmHg 1 mm Hg ±1 mm Hg + 1 least significant digit (Applicable only for XL40 and XL60) 0 to 45 ppt (Applicable only for XL40 and XL60) Operating Conditions operating temperature operation humidity maximum operating altitude installation category Pollution category degree 5-45 °C 5-80 % noncondensing 2000m II 2 (Applicable for XL15, XL20, XL25, XL30, XL40, XL50, and XL60) 4 Getting Started: XL Series Meters Connectors XL15 and 20 meters 1. Review the layout and arrangement of the rear connector panel. XL15 rear connector panel XL20 rear connector panel 5 Getting Started: XL and Shut down procedures Getting Started: StartupSeries Meters Connectors XL60 meter XL15, 20, 25, 30, 50 and 60 meters Important: It is recommended to follow the following start-up and shut down procedures to avoid crashes, lock-ups or data loss. Start and shut down procedures are also illustrated on the slip attached with the adaptor cable. Start-up procedure: 1. Connect the 9V DC power jack of the adaptor to the rear connector panel of the XL meter. 2. Connect 2 pin power plug into the power outlet or terminal strip. 3. Switch power on (wall socket or terminal strip). 4. Press the black button on the base of the meter for 5 seconds. 5. Release the button to power on the meter. Shut down procedure: 1. 2. 3. 4. Close all applications and log off. From the HOME screen tap the bottom of the screen to bring up the task bar. Tap Start>Shut down. This launches Shut down window. Tap the Yes button on Shut down window to power off the meter. Caution: Do not remove power from the XL meter until the meter shuts down. 9 Getting Started: XL and Shut down procedures Getting Started: StartupSeries Meters Connectors X 40 meter XLL60 meter Important: It is recommended to follow the following start-up and shut down procedures to avoid crashes, lock-ups or data loss. Start and shut down procedures are also illustrated on the slip attached with the adaptor cable. Start-up procedure: 1. Connect the 9V DC power jack of the adaptor to the rear connector panel of the XL meter. 2. Connect 2 pin power plug into the power outlet or terminal strip. 3. Switch power on (wall socket or terminal strip). 4. Press the black button on the base of the meter for 5 seconds. 5. Release the button to power on the meter. Shut down procedure: 1. 2. 3. 4. Close all applications and log off. From the HOME screen tap the bottom of the screen to bring up the task bar. Tap Start>Shut down. This launches Shut down window. Tap the Yes button on Shut down window to power off the meter. Caution: Do not remove power from the XL meter until the meter shuts down. 10 Getting Started: pH and Ion Probes XL15, 20, 25, 50 and 60 meters The XL series meters - XL15, XL20, XL25, XL50 and XL60 - allows you to use two types of pH electrodes: the conventional glass pH electrode and the AccuFET field effect transistor (FET) pH electrode. 1. Carefully remove the protective cover from the end of the electrode. Before first using your glass pH electrode, or whenever the electrode is dry, soak it 2-4 hours in an electrode storage solution, pH 4 Buffer, or KCl solution. 2. Remove the shorting cap on BNC connector. Connect the combination pH electrode by plugging it into the BNC input connector (twisting to lock in place). If a combination electrode isn’t used, connect the indicating pH electrode into the BNC input connector. Plug the reference electrode into the reference pin jack. Also, install the ATC probe into the ATC jack. Note: Be sure to connect all probes to the appropriate channel connectors (for example: pH1, Ref 1 and ATC1). Option: Connect the optional AccuFET electrode by plugging it into the FET jack on the back meter panel. Allow the AccuFET to warm up five minutes before use. Connect ion specific electrodes in the same manner as pH electrodes. Shorting cap Do not discard the BNC shorting cap. 11 Getting Started: pH and Ion Probes XL15, 20, 25, 50 and 60 meters 3. Rinse and blot-dry (don't wipe) electrodes between each measurement. Rinse electrodes with distilled or deionized water, or a portion of the next solution to be measured. 4. Between measurements, store conventional pH electrodes in electrode storage solution, pH 4 buffer, or KCl solution. Always leave the filling hole of liquid filled combination electrodes open. Refill when the level of solution gets below the manufacturer's recommended level. Store ion specific electrodes according to electrode manufacturer’s recommendations. Proper electrode care is fundamental to obtaining reliable pH measurements. Improper care of the electrode may cause the meter reading to drift, respond slowly, or produce erroneous readings. For this reason, the electrode should always be conditioned and used in accordance with manufacturer’s instructions. 12 Using the XL Series Meter: Touch Screen Operation XL15, 20, 25, 30, 40, 50 and 60 meters When the meter is turned on it first goes though self test, displays the FISHER Catalog cover, briefly displays the desktop screen (Home) before loading the XL series program which results in the display of the measurement screen. Example:- XL 60 Desktop screen (Home) Example of XL series measurement screen: XL60 meter - pH, pH, DO, and conductivity quadruple measurement screen 15 Using the XL Series Meter: Touch Screen Operation XL15, 20, 25, 30, 40, 50 and 60 meters The new accumet XL series benchtop meter operates with a state-of-the-art touch screen. The touch screen makes this the easiest meter on the market to operate and care for. When the meter is first plugged in, the meter runs a self-test and takes you to the measurement screen. Touch any icon to access the functions of the meter. Your XL series meter also includes a stylus that you can use to tap on your screen. The stylus easily stores inside the back panel of the meter. The buttons on the right side of the screen control all of the functions of the meter. A light touch on the screen is all that you need to access the various functions. Once you touch a button you will get an audible tone; the screen will not change until you lift your stylus. This design prevents rapid uncontrolled scrolling through the various function screens. Function buttons and options change from screen to screen. Easy to understand prompts guide you through the operation of the meter in the selected mode. If you are ever in doubt about what to do, just touch Help on the bottom right corner of the screen for detailed information about that screen. Your meter was shipped with a clear protective sheet to protect the LCD display and “bubbles” may appear on the screen. The screen will respond better and visibility will improve if it is removed. Alternatively, you may choose to leave this on for added protection. Screen contrast adjustment You can adjust the contrast of your screen to your requirements. 1. From the HOME screen, tap the bottom edge of the screen to access the Task bar. Tap Start > Settings > Control Panel. This launches the Control Panel screen. 2. Double tap the Display Contrast icon. 3. Tap the up and down arrows to select your desired contrast level. 4. Tap the Close key to exit control adjustment. 16 Using the XL Series Meter: Using the Stylus XL15, 20, 25, 30, 40, 50 and 60 meters Your XL series meter comes with a stylus that you should use to tap on your screen. The stylus easily stores inside the back panel of the meter. You can perform two basic actions using the stylus: Tap Lightly touch the screen to select or open an item. Lift the stylus after you tap an item. Tapping is equivalent to clicking an item with the mouse on your personal computer. Note: Some program items require a double tap to select or launch. Double tap on the icons from the Desktop (Home) page and single click in the XL series icon application. Drag Place the point of the stylus on the screen and drag an item across the screen without lifting the stylus until you have completed the selection. Dragging is equivalent to dragging with the left mouse button pressed on your personal computer. Stylus Calibration If the meter is not responding properly to your taps, you may need to recalibrate your screen. 1. From the HOME screen, tap the bottom edge of the screen to access the Task bar. Tap Start > Settings > Control Panel. This launches the Control Panel screen. 2. Double tap the Stylus icon. 3. Tap the Calibration tab to access the calibration screen. 4. Tap the Recalibrate button. 5. Carefully tap and briefly hold the stylus on the center of the target. Repeat tapping the target as it moves to the 4 corners of the screen. If you miss the target center, keep the stylus on the screen, slide it over the target’s center, and then lift the stylus. 6. Once the calibration is complete, the target will disappear. Tap anywhere in the screen to accept the new calibration and go back to the “Stylus Properties” window. Tap OK to close the “Stylus Properties” window. CAUTION: To prevent damage to your XL series meter screen, never use any device other than the stylus that comes with the meter or an approved replacement to tap on the screen. Order extra or replacements if you lose or break your stylus. 17 Using the XL Series Meter: Setting Time and Date XL15, 20, 25, 30, 40, 50 and 60 meters Setting the Time 1. From the HOME screen tap the bottom left of the screen to access the Start menu. Tap Start > Settings > Control Panel. This launches the Control Panel screen. 2. Double tap Date/Time icon. This launches the Date/Time Properties window. 3. Tap the time-zone down arrow, and select the appropriate time zone. 4. Tap the hour, minutes, or seconds. Tap up and down arrows to adjust. 5. Tap AM or PM. Use up and down arrow to select. 6. Tap Apply button. 7. Tap OK to save the time. Setting the Date 1. From the HOME screen tap the bottom left of the screen to access the Start menu. Tap Start > Settings > Control Panel. This launches the Control Panel screen. 2. Double tap Date/Time icon. This launches the Date/Time Properties window. 3. Tap the left or right arrow to select a month and year. 4. Tap a day. 5. Tap Apply button. 6. Tap OK to save the time. You need to reset your time zone, time, and date if: • The time changes or you are traveling to a different time zone. The time on the meter can be synchronized with your personal computer through Microsoft® "Active sync". 18 Using the XL Series Meter: On-Screen Keyboard XL15, 20, 25, 30, 40, 50 and 60 meters Using the On-Screen Keyboard Use the stylus to tap letters, numbers, and symbols on the on-screen keyboard to enter typed text directly onto the screen. 1. From any application, screen tap the bottom right of the screen to access the input panel. Tap the Pencil/Keyboard icon (see below). A pop-up menu will appear. 2. Tap LargeKB to display a large keyboard with all function keys. Tap keyboard for a basic function alphanumeric keyboard. 3. Tap desired letters, numbers and symbols on the keyboard. Hit the Enter key. 4. To remove the keyboard, tap on the Pencil icon. The pop-up menu will appear. Tap Hide Input Panel to remove keyboard. To see symbols, tap the Shift key. 19 Using the XL Series Meter : Expansion Cards XL15, 20, 25, 30, 40, 50 and 60 meters Secure Digital (SD) Expansion Cards You can expand the memory and connectivity of your XL series meter. Use optional expansion cards for: • Expanding the memory of your XL series meter • Viewing the content of memory cards Expansion cards must be purchased separately and are not included with your XL60 meter. Installing an Secure Digital (SD) Expansion Card To install a Secure Digital (SD) card into an expansion slot on the XL series meter: 1. Locate the SD card slot on the back of XL series meter. 2. Remove the protective plastic card. 3. Insert the SD card into the SD slot and push firmly If your expansion card is not recognized, follow the card manufacturer’s instructions to install it. Removing a Secure Digital (SD) Expansion Card 1. Close all applications that are using the SD card. 2. Remove SD card from the SD slot by slightly pushing down on the card to unlock it. 3. When the card disengages and pops up, pull it from the expansion slot. CAUTION: SD cards must first be unlocked before removal. Viewing the Content of Secure Digital (SD) Expansion Cards Use Windows Explorer to view the files that are located on your optional Secure Digital card. 1. From the Start menu, tap Programs >Windows Explorer. 2. Tap the root directory of My Device, and select the Storage Card folder (SDIO) to see a list of files and folders. 20 Using the XL Series Meter: Connecting to the Internet XL15, 20, 25, 30, 40, 50 and 60 meters Connecting the Internet The XL series meter allows you to connect internet through the RJ-45 port located at the back panel of the XL series. 1. Connect Internet cable to RJ-45 port on the back of the XL Series meter. 2. Power on the XL Series meter. 3. To access and view websites on XL series meter follow the steps mentioned below. Entering an Internet Address With Pocket Internet Explorer and a connection to the Internet, you can view Web sites on your XL series meter by typing an address or Universal Resource Locator (URL) in the Address bar. Web sites that use HTML 4.0, DHTML, animated GIF images, and Java applets may not work correctly in Pocket Internet Explorer without additional software. To enter an Internet address (URL) on your XL series meter: 1. From the Start menu, tap Programs > Internet Explorer > Address Bar. If the Address Bar is not visible, tap the View tab > Address Bar to turn it on. You may also double tap the Internet Explorer icon on the Home screen to launch Internet Explorer. 2. Enter the Internet address (URL) in the Address bar using the on-screen keyboard. 3. Tap the Go icon. Caution: The internet cable should be connected to the RJ-45 port before the XL meter is switched on to avail the internet connection. If user tries to connect cable after the meter is switched on, the screen will display ’The page cannot be displayed’. Using a Favorites List With Pocket Internet Explorer and a connection to the Internet, you can view Web sites on your XL series meter by selecting one from your Favorites list. To select a Web site from your Favorites list: 1. From the Start menu, tap Internet Explorer. 2. Tap the Favorites icon and the Web site you want to view. 21 Using the XL Series Meter: Button Functions XL15, 20, 25, 30, 40, 50 and 60 meters The touch screen of your XL series bench meter has “buttons” along the right side of the screen that are common to many of the screens. The following indicates the function of these common buttons. The Channel 1, Channel 2, Channel 3, Channel 4 and Channel 5 buttons access the single display screen corresponding to each channel. If you wish to perform standardization or printing from any of the channels, you need to use single channel mode. The Graph can only be viewed in the single channel mode. Channel 1 Channel 2 Channel 3 Channel 4 Channel 5 pH, mV or *(ion) channel pH, mV or *(ion) channel pH (FET) channel DO, BOD, OUR, SOUR channel Conductivity, Resistivity, TDS or Salinity channel NOTE: *(ion) channel is for XL25, XL50 and XL60 meters only. Available in XL15, XL20, XL25, XL50 and XL60 Available in XL25, XL50 and XL60 Available in XL15, XL20, XL25, XL50 and XL60 Available in XL40 and XL60 Available in XL20, XL30, XL 50 and XL60 The Mode button allows you to switch between the various operations of the meter— pH, mV, ion, pH (FET), DO, conductivity, resistivity, TDS and salinity. It also lets you configure the display options, select input parameters, and view the software revision and serial number details. The Setup button will access the setup screens of the channels that you are currently using. The Log Data button sends data to the data storage center of the meter if sample ID # has been assigned to your sample. The Profile button lets you view your profile (User ID, Password, Company Name, User Group). You can change only your profile and not of any other user. You can change to a different user only if you are the default user of the system. The Home button accesses the Windows CE desktop. The XL series application does not shut down if Home is pressed and the current user remains logged in. Double tap on the XL series icon to return to the previous screen before the Home button was pressed. The Logoff button allows you to logoff the current user from the XL series application. The XL series application shuts down returning to the Win CE desktop. When you restart the application, you go to the main screen of the application. The second time you are logged in as the default user of the system. The Help button allows you to access helpful information on any screen. Touching the Help button gives you information about the current screen. This information will include step-by-step instructions for operating the meter from the current screen and possible applications information for that screen. 22 Using the XL Series Meter: Button Functions XL15, 20, 25, 30, 40, 50 and 60 meters The following buttons appear in the XL series meters Mode screen: *Replatinization is the process of replacing the platinum on the surfaces of the 2 cell conductivity probes that may flake or wear off over time. The platinum on the surface of the probe is used to increase the surface area of the measuring surface resulting in decreased polarization error. Replatinization is a relatively quick procedure to perform, taking no more than 5 minutes. See ‘Appendix: Replatinization’ for procedure. *Note: Replatinization function is available in XL20, XL30, XL50 and XL60 meters only. The About button lets you view the software revision and serial number details. The Sys.Setup button allows you to turn on or off the beep status. This is the audible beep that sounds each time any button is touched. The *Multi Channel button lets you view multiple channels at the same time. *Note: This is available in XL20, XL25, XL50 and XL60 meters only. Single Channel Display ● XL15 (Display - Ch1/Ch3) ● XL30 (Display – Ch5) ● XL40 (Display – Ch4) ● XL20 (Display 1 & 2 - Ch1/Ch3/Ch5) ● XL25 (Display 1 & 2 - Ch1/Ch2/Ch3) ● XL50 (Display 1, 2 & 3 – Ch1/Ch2/Ch3/Ch5) ● XL60 (Display 1 , 2 , 3 & 4 – Ch1/Ch2/Ch3/Ch4/Ch5) Dual Channel Display Triple Channel Display Quadraple Channel Display The *Display Setup button lets you configure the display to read the inputs from the channels of your choice. *Note: Display Setup function is available in XL20, XL25, XL50 and XL60 meters only. 23 Using the XL Series Meter: Button Functions XL15, 20, 25, 30, 40, 50 and 60 meters The following buttons appear in the related XL series meters Mode screen after Channel 1, 2, 3, 4 or 5 is selected: The pH mode button allows you to switch to the various pH operations of the meter (available in Ch 1 and 2 of the XL15, XL20, XL25, XL50, and XL60 meters only). The mV mode button allows you to switch to the various mV operations of the meter (available in Ch 1 and 2 of the XL15, XL20, XL25, XL50, and XL60 meters only). The Ion mode button allows you to switch to the various ion concentration operations of the meter (available in Ch 1 and 2 of the XL25, XL50, and XL60 meters only). The pH (FET) mode button allows you to switch to the various pH (FET) operations of the meter (available in Ch 3 of the XL15, XL20, XL25, XL50, and XL60 meters only). The DO mode button allows you to switch to the various dissolved oxygen operations of the meter (available in Channel 4 of the XL 40 and XL60 meters only). The BOD button allows you to enter the BOD Parameter Calculations Screen in the BOD measurement screen (available in Channel 4 of the XL 40 and XL60 meters only). The OUR button allows you to Start and Stop the OUR measurement in the OUR measurement screen (available in Channel 4 of the XL 40 and XL60 meters only). The SOUR button allows you to Start and Stop the SOUR measurement in the SOUR measurement screen (available in Channel 4 of the XL 40 and XL60 meters only). The Conductivity mode button allows you to switch to the various conductivity operations of the meter (available in Channel 5 of the XL 20, XL30, XL50 and XL60 meters only). The Resistivity mode button allows you to switch to the various resistivity operations of the meter (available in Channel 5 of the XL 20, XL30, XL50 and XL60 meters only). The TDS mode button allows you to switch to the various TDS operations of the meter (available in Channel 5 of the XL 20, XL30, XL50 and XL60 meters only). The Salinity mode button allows you to switch to the various salinity operations of the meter (available in Channel 5 of the XL 20, XL30, XL50 and XL60 meters only). 24 Using the XL Series Meter: Button Functions XL15, 20, 25, 30, 40, 50 and 60 meters The following button appears in all XL series meters single channel screens: The Print button will send information to the output device that is connected to your meter. If you selected the “Log data” option in the “Print criteria” setup, clicking on the print button will dump the logged data to the printer. The Standardize button accesses the standardization screen from the various measure modes and initiates standardization of the meter once the standardization screen is accessed. Not available from mV screen. The Measure button directs the meter to measure your sample when in the Auto Read function. Not available from mV, BOD, OUR, and SOUR screens. The following buttons appear in the XL15, XL20, XL25, XL50 and XL60 meters mV single channel screen: The rel mV button returns the meter into the relative millivolt mode when in the absolute mV mode. When this mode is activated, a window will appear asking you to set a relative mV value or accept the default value of 0 mV. This feature may assist the user to standardize certain analytical and monitoring activities such as titration. The abs mV button returns the meter to absolute millivolt mode when the meter is in relative mV mode. It only appears when the meter is in the relative mV mode. The following buttons appear in the XL40 and XL 60 meters *Dissolved Oxygen channel screen: The BOD button allows you to enter the BOD Parameter Calculations Screen from the BOD measurement screen. The OUR button allows you to Start and Stop the OUR measurement from the OUR measurement screen. The SOUR button allows you to Start and Stop the SOUR measurement from the SOUR measurement screen. The following buttons appear in all XL series meters standardization screens: The Confirm button accepts current value of the buffer or standard solution. The Clear button clears all previous standardization points. The Cancel button cancels current standardization and returns to the measurement screen. The Temp Std button allows you to check the accuracy of your temperature probe and standardize to an accurate thermometer. 25 Using the XL Series Meter: Channel Assignment XL15, 20, 25, 30, 40, 50 and 60 meters The XL series meters features up to five channels depending on the models you have purchased. ● XL15 – Channel 1/3 (pH,mV / pH FET) ● XL20 – Channel 1/3/5 (pH,mV, / pH FET / Conductivity,Resistivity,TDS,Salinity) ● XL40 – Channel 4 (DO,BOD,OUR,SOUR) ● XL50 – Channel 1/2/3/5 (pH,mV,ion / pH FET / Conductivity,Resistivity,TDS,Salinity) ● XL25 – Channel 1/2/3 (pH,mV,ion / pH FET) ● XL 60 – Channel 1/2/3/4/5 (pH,mV,ion / pH FET / DO,BOD,OUR,SOUR /Conductivity,Resistivity,TDS,Salinity) ● XL30 – Channel 5 (Conductivity,Resistivity,TDS,Salinity) Assigning the channels 1. Touch the Mode button on the Measure screen. 2. Choose the desired channels for your application. • XL15 - Touch the input channel (Ch1 and/or Ch3) on the back panel image to select the parameter assigned to that channel. Touch the appropriate parameter icon to assign an input to each desired channel. • XL30 and XL40 - Touch the appropriate parameter icon to assign an input to each desired channel. • XL20, XL25, XL50 and XL60 - Touch Channel button (Ch1, Ch2, Ch3, Ch4 and/or Ch5) to select the parameter assigned to that channel. Touch the appropriate parameter icon to assign an input to each desired channel. 3. To deselect a channel, simply touch the Channel button again (or input channel on back panel). 4. If multiple channels are assigned, touch the Display Setup button to select and assign displayed windows (refer to next page for directions). 5. To return to measurement mode, touch Multi Channel (if two or more channels are assigned) or touch Single Channel (if one channel is assigned). Assigning channel for XL15 meter 26 Using the XL Series Meter: Channel Assignment XL15, 20, 25, 30, 40, 50 and 60 meters Assigning channel for XL30 t Assigning channel for XL40 t Assigning channels for XL20, XL25, XL50 and XL60 (example shown is XL60) Based on the assigned channels, selected meter models can feature up to a quadruple (XL60), triple (XL50), dual (XL20 and XL25), or single (XL15, XL30 and XL40) display mode where all selected screens are shown simultaneously. The parameters being displayed is based on the Display Setup (see ‘Using the XL Series Meter: Display Setup’ section for directions). This is only available in XL20, XL25, XL50 and XL60 meters since XL15, XL30 and XL40 meters features only single display mode. 27 Using the XL Series Meter: Display Setup XL15, 20, 25, 30, 40, 50 and 60 meters Your XL series meters have the following display configuration: ● XL15 – 1 Display (Selectable from Ch1/Ch3) ● XL20 – Up to 2 Displays (Selectable from Ch1/Ch3/Ch5) ● XL40 – 1 Display (Selection from Ch4) ● XL50 – Up to 3 Displays (Selectable from Ch1/Ch2/Ch3/Ch5) ● XL25 – Up to 2 Displays (Selectable from Ch1/Ch2/Ch3) ● XL 60 – Up to 4 Displays (Selectable from Ch1/Ch2/Ch3/Ch4/Ch5) ● XL30 – 1 Display (Selection from Ch5) According to the above configuration, the Display Setup mode lets you select which channel will appear in each display. Access the Display Setup button from the Mode screen when multiple channels are selected. To configure the display: 1. Touch the desired Display box. 2. Touch any one of the Channel boxes to the right of the display box to assign the channel to the selected display. 3. To reassign any of the displays, touch the Display box again and the allocation clears. Touch the M. Channel button to save the configuration and return to the Measurement screen. Touch the OK button to save the display configuration and return to the Mode screen. Touch the Cancel button to exit and return to the Mode screen without saving changes. When you touch the Help button, information about the current screen appears. This information includes step-by-step instructions for operating the meter from the current screen and possible applications information for that screen. Example: - XL60 Display Setup screen 28 pH Setup: pH Setup Screen XL15, 20, 25, 50 and 60 meters Available only in XL15, XL20, XL25, XL 50 and XL60 meters, the pH Setup screen presents many options to control the pH operating parameters of the meter. The meter is factory set with regard to these options, and is ready for use under most circumstances (see ‘Appendix: XL Series Meters Factory Default Settings’ section for default settings). The pH Setup section will guide you through the various options available in the pH setup mode. Example: - XL60 pH Setup screen Function Buttons on pH Setup Screen Touch OK to confirm pH Setup and return to the pH Measure screen. Touch Cancel to exit and return to the pH Measure screen without confirming pH Setup. Touch View to view all pH data points stored in memory. See ‘pH Setup: View Stored Data’ section for details. When you touch the Help button, information about the current screen appears. This information includes step-by-step instructions for operating the meter from the current screen and possible applications information for that screen. Touch Reset to reset all pH Setup Criteria to the factory default. 29 pH Setup: Access pH Setup XL15, 20, 25, 50 and 60 meters To access the Setup screen: 1. Make sure you are in the pH Measure screen. 2. Touch the Setup button to access the pH Setup screen. If you were in quadruple, triple or dual display mode, you have access to the Setup mode for each channel displayed. Touch the Setup Channel buttons at the top of the screen to toggle back and forth between the setup screens for each channel. To change pH parameters, select the pH Setup button. If you were in single display mode, you will access the Setup mode for the single channel displayed only. 30 pH Setup: Set Sample ID# XL15, 20, 25, 50 and 60 meters A sample ID is required if you wish to log data or activate a timed printing. Whenever this option is active, each time you touch Log Data (available on the single display pH Measure screen), the pH (or pH FET) value along with date/time/channel and the sample ID will be sent to data storage. You can manually enter an alphanumeric identification number of 10 characters for any sample or you can have the meter sequentially number your samples beginning at the number of your choice. You can also choose to deactivate the sample ID. To set sample ID — Manual: 1. Touch Manual for manual Sample ID entry 2. The current ID is displayed on the screen 3. Use the alphanumeric keypad on the screen to enter the desired Sample ID. The BS key will allow you to backspace to remove a character that was incorrectly entered. 4. Touch Enter to accept current Sample ID and return to the pH (or pH FET) Setup screen. To set sample ID — Sequential 1. Touch Sequence for sequential Sample ID entry 2. The current ID is displayed on the screen 3. Use the numeric keypad on the screen to enter the desired Sample ID number that you would like your sequential Sample ID assignment to begin with. Every time you touch Print or Log Data on the pH Measure screen, the Sample ID will increase by 1. The BS key will allow you to backspace to remove a character that was incorrectly entered. 4. Touch Enter to accept the first sequential Sample ID and return to the pH (pH FET) Setup screen. To deactivate the sample ID assignment — None 1. Touch None to deactivate the sample ID assignment 31 pH Setup: Select Buffer Group XL15, 20, 25, 50 and 60 meters This setup option allows you to select from 3 different buffer groups, for auto buffer recognition. Or you can create a custom group of buffers for auto buffer recognition by touching custom. The 3 existing buffer groups are: USA buffers: 2.00, 4.00, 7.00, 10.00, 12.00 European buffers: 1.00, 3.00, 6.00, 8.00, 10.00, 13.00 NIST buffers: 1.68, 4.01, 6.86, 9.18, 12.45 To select a buffer group 1. Touch USA, EURO, NIST or CUSTOM from the setup screen to select a buffer group. To set a Custom pH buffer group This option allows you to create a custom buffer group of up to 5 buffers (2 buffer minimum) to be used for auto buffer recognition. To obtain optimal results, it is important to maintain at least 1 pH unit between selected buffers in the custom group. 1. Touch CUSTOM on the setup screen to select a custom buffer. This will display a set of 5 custom beakers each initialized to zero. 2. Touch one of the beakers to display the numeric keypad. 3. Enter a value for the custom pH buffer that you want set in your custom buffer set. 4. Press Enter in the keypad to accept the value. 5. Repeat steps 2 through 4 until all 5 custom buffer beakers are populated with desired values. 6. To modify the value entered, touch the particular beaker and key in the new value using keypad. 7. To clear all custom buffer values, touch CLEAR. 32 pH Setup: Select Auto Read Mode XL15, 20, 25, 50 and 60 meters Select Buffer Recognition This option allows you to select Automatic buffer recognition or manual buffer recognition when standardizing. With the automatic buffer recognition activated, the meter will automatically recognize the buffers from the chosen buffer group and accept them when the meter recognizes the reading as stable. When in the Manual buffer recognition mode, you must enter the buffer value during the standardization procedure. The meter will accept the manually entered buffer when you recognize that the measurement is stable. During the standardization procedure, you may accept the buffer value before the meter recognizes it as stable by touching the Standardization button. To select Buffer Recognition 1. Touch MANUAL or AUTO to choose the method of buffer selection Select Auto Read Mode You can use this meter when the Auto Read function is active or when it is inactive. When the Auto Read function is active, the meter will lock onto a reading when the meter recognizes it as stable. The meter will not deviate from this reading until Measure is touched. If the Auto Read function is inactive, then the meter will continuously monitor the pH of the sample and the Measure screen display will indicate any fluctuation in the sample pH. To select Auto Read Mode 1. Touch MANUAL or AUTO to choose the desired read mode. 33 pH Setup: Set Default Temperature XL15, 20, 25, 50 and 60 meters Set pH Stability Criteria This setup screen allows you to determine how quickly the meter will respond to electrode drift. There are 3 speed settings: fast, medium and slow To set pH Stability Criteria 1. Touch FAST, MEDIUM, SLOW to choose the desired stability criteria. Stability criteria are more stringent at the slower setting. Therefore, if the highest precision is required, then a slow setting would be desired. The default setting is the FAST and this should be adequate for the majority of applications without making any changes. Set Default Temperature It is a well known fact that pH is a temperature dependent measurement. The factory default setting is 25°C. If you are taking the pH of a solution that is not 25°C and you are not using an Automatic Temperature Compensation (ATC) probe, then you should enter the temperature value of that solution in order to get the correct pH value. The current default temperature setting will be displayed on the screen. The default temperature can be set from -5°C to 105°C. To set Default Temperature 1. Select temperature units by touching the appropriate unit button: C (Celsius), F (Fahrenheit) or K (Kelvin) 2. Touch the Default Temperature box and use the numeric keypad to enter the desired default temperature (-5°C to 105°C). 3. Press Enter in the keypad to return to pH (pH FET) Setup screen The use of an ATC probe provides a measured temperature value to the meter and will override any value entered in the default temperature screen. This measured value will be used by the meter to make pH calculations. 34 pH Setup: Set Alarm Limits XL15, 20, 25, 50 and 60 meters To set Isopotential Point The isopotential point is the millivolt reading for an electrode at which temperature has no effect on the measurement. pH electrodes are constructed so that the isopotential point is theoretically zero millivolts. This is very close to a pH of 7. Most pH electrodes do not achieve this value precisely. However they are close enough so that it is not usually necessary to use an isopotential point other than zero. The true isopotential point of any given electrode must be determined experimentally. (See Appendix: Determining Isopotential Points Experimentally). The isopotential point can be set from -100 to +100. To set Isopotential Point 1. Touch the Isopotential Point box and use the numeric keypad to enter the desired mV setting for the new isopotential point. 2. Touch Enter to accept this value and return to pH (pH FET) Setup screen. To set Alarm Limits This option allows you to set alarm limits for the pH measuring mode. If the pH value of the measurement is outside of the boundaries set by the minimum and maximum limits, audible and visual warnings will let you know that your sample measurement was outside of the set limits. For the pH mode, the alarm limit can be set from -2 pH to 20 pH. As for the pH (FET) mode, the alarm limit can be set from 0 pH to 14 pH. To set Alarm Limits 1. Touch ON or OFF to set the status of the alarm of pH (pH FET) mode 2. Touch the Low box and use keypad to enter the new limit values. 3. Touch Enter on the keypad to accept this limit and return to the pH (pH FET) Setup screen. 4. Touch the High box and use keypad to enter the new limit values. 5. Touch Enter on the keypad to accept this limit and return to the pH (pH FET) Setup screen. 35 pH Setup: Set Print Criteria XL15, 20, 25, 50 and 60 meters This screen allows you to select which criteria are printed with the measurement when you print the data. The status of the current print criteria is displayed on the screen. The criteria option is active if ON appears to the right of the option. It is inactive if OFF appears to the right of the option. Any active criteria will be printed on demand. To set Print Criteria 1. Touch the Touch here to edit button next to the Print Criteria to access the pH Print Criteria Setup screen. 2. Touch ON or OFF to change the status of a criteria you want to modify. 3. Repeat step 2 for all the remaining criteria except Print Interval (or Print Option). 4. For Print Interval (or Print Option) select between Log Data and Timed. If “Log Data” is selected, clicking on the “Print” button from the Measurement screen will send the logged data to the printer. If “Timed” is selected, you can print data at an interval you select. This data is buffered and is sent to the printer when the page is full. 5. Touch OK button to accept the changes of the entire group of print criteria and return to the pH (pH FET) Setup screen. 36 pH Setup: Set Data Storage Criteria XL15, 20, 25, 50 and 60 meters This screen allows you to select which criteria are stored in the data logger with the measurement when you store the data. The status of the current data storage criteria is displayed on the screen. The criteria option is active if ON appears to the right of the option. It is inactive if OFF appears to the right of the option. Any active criteria will be stored on demand. To set Data Storage Criteria 1. Touch the Touch here to edit button next to the Data Storage Criteria to access the pH Data Storage Setup screen. 2. Touch ON or OFF to change the status of a criteria you want to modify. 3. Repeat step 1 for all the remaining criteria except Data logging Interval (or Data storage Interval). 4. For Data logging Interval (or Data storage Interval), touch MANUAL to log pH data only when the Log Data button is pushed, touch STABLE to automatically log pH data when the pH reading is stable, or touch TIMED to set a specific timed interval in seconds to log pH data. 5. Touch the OK button to accept the changes of the entire group of data storage criteria and return to the pH (pH FET) Setup screen. 37 pH Setup: Set Display Criteria XL15, 20, 25, 50 and 60 meters This screen allows you to choose what information you would like to be displayed on the pH Measure screen, particularly the information contained in the data box at the bottom of the Measurement screen. The status of the current display criteria is displayed on the screen. The criteria option is active if ON appears to the right of the option. It is inactive if OFF appears to the right of the option. To set Display Criteria 1. Touch the Touch here to edit button next to the Display Criteria to access the pH Display Criteria Setup screen. 2. Touch ON or OFF to change the status of a criteria you want to modify. 3. Repeat step 2 for all the remaining criteria except Display Resolution. 4. For Display Resolution, touch X.X to display pH with one decimal place, touch X.XX to display pH with two decimal places, or touch X.XXX to display pH with three decimal places. 5. Touch the OK button to accept the changes of the entire group of display criteria and return to the pH (pH FET) Setup screen. 38 pH Setup: View Stored Data XL15, 20, 25, 50 and 60 meters The XL15, XL20, XL25, XL 50 and XL60 have a memory capacity to store up to 1000 data points. The View Stored Data screen allows you to look at specific data points stored in the meter based on the meters memory capacity. The meter stores pH or pH (FET) data under the following parameters: Reading Date / Time / Channel Sample Id Temperature Current Buffers To View Stored Data 1. Touch the View button in the pH Setup screen. mV Measurement Slope Last Standardizations Meter Model / Serial No Operator You can only log 1000 data points at a time. To clear space for new data points, you have to delete the same number of old data points as you want to add new data points. Function buttons on View Stored Data Screen Touch OK to go back to the pH Setup screen from the View Stored Data screen. When you touch the Help button, information about the current screen appears. This information includes stepby-step instructions for operating the meter from the current screen and possible applications information for that screen. Touch Delete to delete a selected data point from the list. To delete a data point, first touch the data point you want to delete then touch the Delete button. Touch Delete All to delete all the data point in the memory. Touch Print to print all the data points in the memory. See next page on Export View and Header (or Export View) for explanation. 39 pH Setup: View Stored Data XL15, 20, 25, 50 and 60 meters Touch Export View and Header (or Export View) to save your data in HTML format. The file can be stored in either the Nand flash, SD Card or any of the other available locations as shown in the window. After having selected the path, touch the alphanumeric keypad to name your file. Touch the alphanumeric keypad to name your file. Export view in HTML format 40 mV Setup: mV Setup Screen XL15, 20, 25, 50 and 60 meters Available in XL15, XL20, XL25, XL 50 and XL60 meters, the mV Setup screen presents many options to control the operating parameters of the meter. The meter is factory set with regard to these options, and is ready for use under most circumstances (see ‘Appendix: XL Series Meters Factory Default Settings’ section for default settings). The mV Setup section will guide you through the various options available in the mV setup mode. Example: - XL60 mV Setup screen Function buttons on mV Setup Screen Touch OK to confirm mV Setup and return to the mV Measure screen. Touch Cancel to exit and return to the mV Measure screen without confirming mV Setup. Touch View to view all mV data points stored in memory. See ‘mV Setup: View Stored Data’ section for details. When you touch the Help button, information about the current screen appears. This information includes step-by-step instructions for operating the meter from the current screen and possible applications information for that screen. Touch Reset to reset all mV Setup Criteria to the factory default. 41 mV Setup: Access mV Setup XL15, 20, 25, 50 and 60 meters To access the Setup screen: 1. Make sure you are in the mV Measure screen. 2. Touch the Setup button to access the mV Setup screen. If you were in quadruple, triple or dual display mode, you have access to the Setup mode for each channel displayed. Touch the Setup Channel buttons at the top of the screen to toggle back and forth between the setup screens for each channel. To change mV parameters, select the mV Setup button. If you were in single display mode, you will access the Setup mode for the single channel displayed only. 42 mV Setup: Set Sample ID# XL15, 20, 25, 50 and 60 meters A sample ID is required if you wish to log data or activate a timed printing. Whenever this option is active, each time you touch Log Data on the mV Measure screen, the mV value along with date/time/channel and the sample ID will be sent to data storage. You can manually enter an alphanumeric identification number of 10 characters for any sample or you can have the meter sequentially number your samples beginning at the number of your choice. You can also choose to deactivate the sample ID. To set sample ID — Manual: 1. Touch Manual for manual Sample ID entry. 2. The current ID is displayed on the screen. 3. Use the alphanumeric keypad on the screen to enter the desired Sample ID. The BS key will allow you to backspace to remove a character that was incorrectly entered. 4. Touch Enter to accept current Sample ID and return to the mV Setup screen. To set sample ID — Sequential 1. Touch Sequence for sequential Sample ID entry 2. The current ID is displayed on the screen 3. Use the numeric keypad on the screen to enter the desired Sample ID number that you would like your sequential Sample ID assignment to begin with. Every time you touch Print or Log Data on the pH Measure screen, the Sample ID will increase by 1. The BS key will allow you to backspace to remove a character that was incorrectly entered. 4. Touch Enter to accept the first sequential Sample ID and return to the mV Setup screen. To deactivate the sample ID assignment — None 1. Touch None to deactivate the sample ID assignment 43 mV Setup: Set Alarm Limits XL15, 20, 25, 50 and 60 meters This option allows you to set alarm limits for the mV measuring mode. If the mV value of the measurement is outside of the boundaries set by the minimum and maximum limits, audible and visual warnings will let you know that your sample measurement was outside of the set limits. The Alarm Limit can be set from -2000.0 mV to 2000.0 mV To set Alarm Limits 1. Touch ON or OFF to set the status of the alarm of mV mode 2. Touch the Low box and use keypad to enter the new limit values. 3. Touch Enter on the keypad to accept this limit and return to the mV Setup screen. 4. Touch the High box and use keypad to enter the new limit values. 5. Touch Enter on the keypad to accept this limit and return to the mV Setup screen. 44 mV Setup: Set Print Criteria XL15, 20, 25, 50 and 60 meters This screen allows you to select which criteria are printed with the measurement when you print the data. The status of the current print criteria is displayed on the screen. The criteria option is active if ON appears to the right of the option. It is inactive if OFF appears to the right of the option. Any active criteria will be printed on demand. To set Print Criteria 1. Touch the Touch here to edit button next to the Print Criteria to access the mV Print Criteria Setup screen. 2. Touch ON or OFF to change the status of a criteria you want to modify. 3. Repeat step 2 for all the remaining criteria except Print Interval (or Print Option). 4. For Print Interval (or Print Option), select between Log Data and Timed. If “Log Data” is selected, clicking on the “Print” button from the Measurement screen will send the logged data to the printer. If “Timed” is selected, you can print data at an interval you select. This data is buffered and is sent to the printer when the page is full. 5. Touch OK button to accept the changes of the entire group of print criteria and return to the mV Setup screen. 45 mV Setup: Set Data Storage Criteria XL15, 20, 25, 50 and 60 meters This screen allows you to select which criteria are stored in the data logger with the measurement when you store the data. The status of the current data storage criteria is displayed on the screen. The criteria option is active if ON appears to the right of the option. It is inactive if OFF appears to the right of the option. Any active criteria will be stored on demand. To set Data Storage Criteria 1. Touch the Touch here to edit button next to the Data Storage Criteria to access the pH Data Storage Setup screen. 2. Touch ON or OFF to change the status of a criteria you want to modify. 3. Repeat step 2 for all the remaining criteria except Data logging Interval (or Data storage Interval). 4. For Data logging Interval (or Data storage Interval), touch MANUAL to log mV data only when the Log Data button is pushed, touch STABLE to automatically log mV data when mV reading is stable, or touch TIMED to set a specific timed interval in seconds to log mV data. 5. Touch the OK button to accept the changes of the entire group of data storage criteria and return to the mV Setup screen. 46 mV Setup: Set Display Criteria XL15, 20, 25, 50 and 60 meters This screen allows you to choose what information you would like to be displayed on the mV Measure screen, particularly the information contained in the data box at the bottom of the Measurement screen. The status of the current display criteria is displayed on the screen. The criteria option is active if ON appears to the right of the option. It is inactive if OFF appears to the right of the option. To set Display Criteria 1. Touch the Touch here to edit button next to the Display Criteria to access the mV Display Criteria Setup screen. 2. Touch ON or OFF to change the status of a criteria you want to modify. 3. Repeat step 2 for all the remaining criteria except Display Resolution. 4. For Display Resolution, touch X to set display with 1 mV resolution or touch X.X to set display with 0.1 mV resolution. 5. Touch the OK button to accept the changes of the entire group of display criteria and return to the mV Setup screen. 47 mV Setup: View Stored Data XL15, 20, 25, 50 and 60 meters The XL15, XL20, XL25, XL 50 and XL60 has a memory capacity to store up to 1000 data points. The View Stored Data screen allows you to look at specific data points stored in the meter based on the meters memory capacity. The meter stores mV data under the following parameters: Reading Date / Time / Channel Sample Id Temperature To View Stored Data 1. Touch the View button in the mV Setup screen. Offset Meter Model / Serial No Operator You can only log 1000 data points at a time. To clear space for new data points, you have to delete the same number of old data points as you want to add new data points. Function buttons on View Stored Data Screen Touch OK to go back to the mV Setup screen from the View Stored Data screen. When you touch the Help button, information about the current screen appears. This information includes step-by-step instructions for operating the meter from the current screen and possible applications information for that screen. Touch Delete to delete a selected data point from the list. To delete a data point, first touch the data point you want to delete then touch the Delete button. Touch Delete All to delete all the data point in the memory. Touch Print to print all the data points in the memory. See next page for Export View and Header (or Export View) explanation. 48 mV Setup: View Stored Data XL15, 20, 25, 50 and 60 meters Touch Export View and Header (or Export View) to save your data in HTML format. The file can be stored in either the Nand flash, SD Card or any of the other available locations as shown in the window. After having selected the path, touch the alphanumeric keypad to name your file. Touch the alphanumeric keypad to name your file. Export view in HTML format 49 pH Operation: About pH Measurement XL15, 20, 25, 50 and 60 meters For the XL15, XL20, XL25, XL50 and XL60 meters, in the pH measurement mode, you will able to measure the pH of a wide variety of samples. Before measuring pH, you will need to standardize the meter using buffers with known pH values. It is good practice to standardize the meter frequently using a minimum of two buffers. Using two buffers allows the meter to calculate and display an actual slope for the electrode, and therefore produce more accurate measurements. If there is no standardization in the memory of the meter or if only one buffer has been used to standardize the meter, the slope value will appear as “......”. You can standardize your meter using automatic or manual buffer recognition. With the Automatic buffer recognition activated (ON), the meter will automatically recognize the buffers from the chosen buffer group and flash the current buffer. When the reading is stable, you must confirm the buffer. In the Manual buffer recognition mode, you must enter the buffer value during the standardization procedure. The meter will flash the manually entered buffer you must confirm the buffer when the reading is stable. During the standardization procedure, you may accept the buffer value before the meter recognizes it as stable by touching confirm. See ‘pH Setup: Select Auto Read Mode’ section to select desired buffer recognition. Remember to setup your pH measuring mode parameters. Refer to the pH Setup section for instructions. Connect the electrodes you will be using to the meter. Touch the Channel 1, 2, or 3 buttons (single pH channel screen) to access the standardization screen. Standardization is not available from multiple display modes. pH measure screen without standardization 111 pH Operation: Standardizing XL15, 20, 25, 50 and 60 meters To Standardize the meter with Auto Buffer Recognition 1. Make sure Auto Buffer Recognition is selected in the Setup screen. 2. Immerse your rinsed electrode(s) and temperature probe in a buffer solution from the selected buffer group that you chose during the pH setup process and stir gently. The selected buffer group appears on the standardization screen. 3. Touch Standardize on the Channel 1, 2 or 3 pH measure screen to access the standardization screen. 4. Touch Clear if necessary to delete all previous standardization values. If the screen says “Not standardized” proceed to step 5. 5. The screen will flash a beaker icon of the buffer solution you have selected. When the reading is stable, STABLE appears on the screen. 6. Touch Confirm to standardize buffer. The meter will return to the pH measure screen. 7. Touch Standardize on the pH measure screen to access the standardization screen. Repeat process to standardize with up to 5 buffers. The efficiency of the electrode is reported as the slope. When doing a multi-point standardization, the slopes of the individual segment are calculated by the meter. The slope that appears on the screen is the slope applicable to that zone (in which the measurement is currently being made). For optimal results, the meter should be standardized at a minimum of every 8 hours. For more accurate measurements, the meter should be standardized more frequently. If there is no previous standardization, there is no need to click the Clear button. If your meter already has a calibration in memory, click Clear if you need to clear the previous calibration values. pH calibration screen with Auto Buffer Recognition Once the meter is calibrated, the pH Measure screen shows the buffers that have been standardized and last standardization time/date 112 pH Operation: Standardizing XL15, 20, 25, 50 and 60 meters To standardize the meter with Manual Buffer Recognition The Manual mode requires a minimum two-point calibration. When you press the Enter key after the first calibration point, a message appears: “Minimum 2 buffers need to be standardized to apply the standardization in measurement’. 1. Make sure Manual Buffer Recognition is selected in the Setup screen. 2. Immerse your rinsed electrode(s) and temperature probe in a buffer solution from the selected buffer group that you chose during the pH setup process and stir gently. The selected buffer group appears on the standardization screen. 3. Touch Standardize on the Channel 1, 2, or 3 pH measure screen to access the standardization screen. 4. Touch Clear if necessary to delete all previous standardization values. If the screen says “Not standardized” proceed to step 5. 5. The screen will flash each beaker icon once, then a numberic keypad will appear. Using the displayed keypad input the value of the buffer that you are using to standardize the meter and then touch Enter. The meter now shows the buffer value in the flashing beaker. 6. When the reading is stable, STABLE appears on the screen. Touch Confirm to standardize the buffer. The meter will then return to the pH measure screen. 7. Touch Standardize on the pH measure screen to access the standardization screen. Repeat process to standardize with up to 5 buffers. If there is no previous standardization, there is no need to click the Clear button. If your meter already has a calibration in the memory, use the Clear button if you need to clear the previous calibration values. pH calibration screen with Manual Buffer Recognition Once meter is calibrated, pH Measure screen shows standardized buffers and last standardization time/date 113 pH Operation: Temperature Standardization XL15, 20, 25, 50 and 60 meters To Standardize Temperature of the Meter 1. Touch Standardize on the pH measure screen to access the standardized screen. 2. Immerse your ATC probe into a solution of known temperature, such as a temperature bath, for a few minutes while temperature stabilizes. 3. Make sure ATC probe is attached to meter. 4. Touch Temp Std to access temperature standardization 5. The Temperature Standardization screen appears. Check the current temperature displayed with that of the solution of known temperature. Touch the Standardization Temperature box and use numeric keypad to enter the current temperature. Press Enter to confirm value. 6. Touch OK to confirm Standardization Temperature and return to the pH Measure screen. Touch Reset to reset and enter a new standardization temperature. Touch Cancel to cancel temperature standardization and return to the pH Standardization screen. Note: The meter will not allow entered value to exceed ±5° of the ATC probe value. If entered value exceeds ±5° an error window will appear and you will have to re-enter value or cancel out of the temperature screen. This might indicate that you have a problem with the ATC probe. 114 pH Operation: pH Measurements XL15, 20, 25, 50 and 60 meters The measure screen provides readout of the current sample measurement. You can use this meter when the Auto Read function is active or when it is inactive. When the auto read function is active, the meter will lock onto a reading when the meter recognizes it as stable. The meter will not deviate from this reading until the Measure button is touched. If the Auto Read mode is inactive, then the meter will continuously monitor the pH of the sample and the measure display screen will indicate any fluctuation in the sample pH. Regardless of the status of the Auto Read mode, STABLE will flash as the meter recognizes the measurement as stable. Once the meter is standardized, you are ready to take pH measurements of your sample. pH Measure screen with Auto Read OFF To Measure pH of a Sample with Auto Read ON 1. Immerse the rinsed electrode(s) in the sample and stir gently. 2. Touch Measure to begin measuring your sample. The meter will accept the reading and display STABLE* when the measurement meets the selected stability criteria. OR To Measure pH of a Sample with Auto Read OFF 1. Immerse the rinsed electrode(s) in the sample and stir gently. 2. Record the reading once the measurement has become stable. STABLE* will appear once the meter recognizes that the measurement is stable. * Please note that STABLE will only appear if you have completed a successful two point calibration. NOTES: You can access other functions of the meter with the remaining buttons on the measure screen. • Touching Setup will access the pH Setup screen. • Touching Measure will initiate a new measurement of a sample with Auto Read ON. • At anytime, you can touch Mode to access another mode of operation. 115 pH Operation: Graphing Function XL15, 20, 25, 50 and 60 meters You can view your data as a real-time graph on screen to display mV changes over time. Time is plotted in seconds. The graph refreshes every hour from the start of graphing. 1. To view your data in graph format, touch Show Graph. 2. To start plotting data, touch Start Plotting. To stop plotting data, touch Stop Plotting. Once the plotting is stopped, the displayed graph can be dragged left/right and up/down. 3. To view your data more closely, touch. Zoom In. To view more data at one time, touch Zoom Out. 4. To hide the graph, touch Hide Graph. 116 mV Operation: About mV Measurement XL15, 20, 25, 50 and 60 meters This mode is used to measure oxidation/ reduction potential (ORP/redox), perform titration and to verify the function of the meter.The mV measure function allows you to continuously monitor the mV potential of the electrodes in use. This can be done in either absolute or relative mV. In the millivolts mode, the current millivolt output from the electrodes being used is monitored and displayed on the screen. The meter will continually monitor the millivolts reading in this mode and will not lock onto a single reading. However, once the reading has become stable, a STABLE will be displayed. Remember to setup your mV measuring mode parameter; refer to mV Setup section for instructions. Absolute mV measurement screen Relative mV measurement screen 117 mV Operation: mV Measurement XL15, 20, 25, 50 and 60 meters In the mV mode, you will be able to make measurements in either absolute or relative millivolts, access the mV Setup screens and print your results to a printer or a computer. Connect the electrodes you will be using to the meter. Absolute mV Measurements 1. Access the mV measure screen from the main screen 2. Immerse the rinsed electrode(s) in the sample and stir gently. 3. Record the measurement when STABLE is displayed. Relative mV Standardization and Measurement In the relative mV mode, we have an option either to adjust the displayed value within a ±150 mV window or equate it to zero. 1. Access the mV Measure screen from the main screen. 2. Immerse the rinsed electrode(s) in the mV (ORP) standard solution and wait for STABLE to appear. 3. Touch rel mV to access the Relative mV screen. When rel mV is touched, a dialog box appears. 4. Touch SET to set relative mV using numeric keypad and press Enter to confirm value. OR Touch DEFAULT to accept the default value (0 mV) OR Touch CANCEL to cancel and return to previous screen. 5. The meter is now ready to take relative mV measurements. Rinse the electrode with water and shake dry. Do not wipe the electrode. Wiping the electrode can cause a static charge on the glass bulb that will result in inaccurate readings. 118 mV Operation: Graphing Function XL15, 20, 25, 50 and 60 meters You can view your data as a real-time graph on screen to display mV changes over time. Time is plotted in seconds. The graph refreshes every hour from the start of graphing. 1. To view your data in graph format, touch Show Graph. 2. To start plotting data, touch Start Plotting. To stop plotting data, touch Stop Plotting. Once the plotting is stopped, the displayed graph can be dragged left/right and up/down. 3. To view your data more closely, touch. Zoom In. To view more data at one time, touch Zoom Out. 4. To hide the graph, touch Hide Graph. 119 Warranty / Compliance Meter, Electrode and Probe Warranty Statement The Fisher Scientific Company (“Fisher”) warrants to the direct purchaser that the accumet meters and Accumet, AccuTupH, AccuFET, AccupHast, and Microprobe electrodes will be free from defects in material or workmanship for a specified warranty period. During that period, Fisher will repair or replace the product or provide credit, at its sole option, upon prompt notification and compliance with its instructions. Warranties listed below are from delivery date. WARRANTY FOR METER For Display: 12 months For All Other Meter Components: 36 months WARRANTY FOR ELECTRODES & PROBES For electrode models 13-620-532 to 13-620-539: 6 months For other electrode models: 12 months Unless otherwise agreed, the warranty is limited to the country in which the product is sold. No Fisher employee, agent or representative has the authority to bind Fisher to any oral representation or warranty concerning any product sold. Any oral representation or warranty made prior to purchase of any product and not set forth in writing and signed by a duly authorized officer of Fisher shall not be enforceable by the purchaser. FISHER EXPRESSLY DISCLAIMS ALL OTHER WARRANTIES, EXPRESS OR IMPLIED, INCLUDING THE IMPLIED WARRANTY OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. Fisher’s sole responsibility and the purchaser’s exclusive remedy for any claim arising out of the purchase of any product listed above is repair, replacement or credit as described above, where applicable. In no event: 1) shall the cost of the exclusive remedy exceed the purchase price: 2) shall Fisher be liable for any special, indirect, incidental, consequential, or exemplary damages, howsoever arising, even if Fisher has been advised of the possibility of such damages. Each article that Fisher furnishes will conform to the written specifications given in this manual, or those of a further improved model. Changes are made often to the information in the manual and will be incorporated into future editions. Notice of Compliance WARNING: This meter generates, uses, and can radiate radio frequency energy. If not installed and used properly, that is in strict accordance with the manufacturer’s instructions, it may cause interference to radio communications. It has been tested and found to comply with the limits for a Class A computing device pursuant to Subpart J of Part 15 of FCC Rules, which are designed to provide reasonable protection against such interference when operated in a commercial environment. Operation of this equipment in a residential area may cause interference, in which case the user, at his own expense, will be required to take whatever measures may be required to correct the interference. This product is to be used only as described in the manual. This product is for indoor use only, and must be used in a well ventilated area. WARNING: To meet or exceed FCC regulations and comply with CE requirements, the Fisher-supplied power supply must be used. Use of a power supply that is not approved by Fisher Scientific may cause safety hazards and/or cause unit to exceed EMC limits and/or damage unit. When using this meter with a computer or printer, a shielded RS232 cable must be used to meet or exceed FCC regulations, and comply with CE Mark requirements. 160 Appendix: Setting the XL Series Meters User Profiles XL15, 20, 25, 30, 40, 50 and 60 meters The XL series meters are equipped with a User Profiles setup or the User Profile Management Application. Setting user profiles saves an individual user unique Setup preferences, calibration data and stored data. The meter can be used without setting a user profile but it will recognize all users as Default. Accessing User Profile Screen 1. Touch Home on any measurement or the Mode screen to access the Home screen. 2. Double tap on AdminUser. The User Login dialog box will appear. 3. Touch the User ID box. The alphanumeric keypad will appear. Key in your User ID or "admin". To set up new users or delete users you must log in using the "admin" user ID. The BS key will allow you to backspace to remove a character that was incorrectly entered. Press the Enter key. 4. Touch the Password box, use the alphanumeric keypad on the screen to key in the password. NOTE: When entering the User Profiles setups for the first time, use admin as the Password. Press the Enter key. The User Login screen will appear with User ID and Password entered. Touch Login to enter the User Profiles screen. From this screen you can update Password and Company Name information by tapping in the appropriate boxes, if you are logged in as a user. If you are logged in as "Admin" user ID you can add and delete users. Adding User Profiles 1. After logging in under User ID "admin" the User Detail fields will show information for "Admin". Touch Clear to clear all information from the User detail box to enter a new user. You can now begin entering information for new users 2. Touch the User ID box; use the alphanumeric keypad on the screen to key in the new User ID. The User ID cannot exceed 10 characters. Press Enter key to confirm User ID. 3. Touch the Password box; use the alphanumeric keypad on the screen to key in a Password. The Password cannot exceed 12 characters. Press Enter key to confirm Password. 4. Touch the Confirm Password box; use the alphanumeric keypad on the screen to key in the same password used in step 3. Press Enter key to confirm Password. 5. Touch the Company Name box; use the alphanumeric keypad on the screen to key in the Company Name. Press Enter key to confirm Company name. 6. Touch Add, a dialog box will ask "Are you sure, you want to add this user?" Touch Yes or No. If you touch Yes, the new user will be added. If you touch No, you may still edit the current user. NOTE: The administrator has authority to add or delete user names. Users may modify their password and company name only by entering User ID and Password in place of Admin on the User Login screen. 161 Appendix: Setting the XL Series Meters User Profiles XL15, 20, 25, 30, 40, 50 and 60 meters Function Buttons on User Profiles Screen Touch Add/Modify to add or modify the current details. Touch Delete to delete the user, applicable only to the Administrator. When you touch the Help button, information about the current screen appears. This information includes step-by-step instructions for operating the meter from the current screen. Touch Clear to clear all user details. Touch Exit to User Profiles screen. Touch Apply to current user to apply Default Setting or Delete User Data function buttons to current user only. Touch Apply to all user to apply Default Setting or Delete User Data function buttons to all users. Touch Default Setting to reset current or all users to factory default setting of meter Touch Delete User Data to delete all measurement data for current or all users. 162 Appendix: Setting the XL Series Meters User Profiles XL15, 20, 25, 30, 40, 50 and 60 meters Once you add a User Profile, the User Login dialog box will automatically pop-up when you turn on the meter. You must either log in with the correct password or log in as a Default user. The Default user does not require a password. User Login 1. When the meter is turned on the User Login box will appear on the Home screen. 2. Select a User ID 3. Touch the Password box, use the alphanumeric keypad on the screen to key in the password. The BS key will allow you to backspace to remove a character that was incorrectly entered. Press the Enter key. NOTE: If you selected Default as a User ID, you do not need to enter a password. Touch Login, the meter enters the measurement mode. 163 Appendix: XL Series Meters Factory Default Settings XL15, 20, 25, 30, 40, 50 and 60 meters The following is a list of XL series meters factory default settings. Reset your meter to the factory default settings by accessing the Reset to Factory Defaults from the System Setup screen. Screen Display Configuration Print Configuration Data Configuration Buffer Group Sample ID PH SETUP MODE Isopotential Point Print Interval Display Resolution Buffer Recognition Auto Read Mode Temperature Units Default Temperature Stability Criteria Alarm Limits Alarm Limit Low Alarm Limit High Display Configuration Print Configuration mV SETUP MODE Data Configuration Sample ID Print interval Display Resolution mV Readings Alarm Limits Alarm Limit Low Alarm Limit High Default Setting All parameters ON All parameters ON All parameters ON USA MANUAL 0.0 mV LOG DATA X.XX AUTO MANUAL C (Celsius) 25.0 C FAST OFF -2.00 pH 20.00 pH All parameters ON All parameters ON All parameters ON MANUAL LOG DATA X Absolute mV OFF -2000 mV +2000 mV XL15 XL20 XL25 XL30 XL40 XL50 XL60 ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● 164 Appendix: XL Series Meters Factory Default Settings XL15, 20, 25, 30, 40, 50 and 60 meters Screen Display Configuration Print Configuration Data Configuration Sample ID Isopotential Point Print Interval ION SETUP MODE Display Resolution Auto Read Mode Temperature Units Default Temperature Stability Criteria Ion method Measurement Unit Electrode Type Alarm Limits Alarm Limit Low Alarm Limit High DO / BOD / OUR / SOUR SETUP MODE Display Configuration Print Configuration Data Configuration Sample ID Calibration Mode Print Interval Display Resolution Temperature Units Stability Criteria Alarm Limits Alarm Limit Low Alarm Limit High DO Measurement Units Auto Read Mode Measurement Units BOD Seed Min Delta DO Seed Min DO Endpoint Sample Min Delta DO Sample Min DO Measurement Units Dilution Factor (1 to X) Minimum Time (min) Maximum Time (min) Minimum Starting DO Minimum Ending DO Solids Weight (g/L) Default Setting All parameters ON All parameters ON All parameters ON MANUAL 0.0 mV LOG DATA 3 Significant digits MANUAL C (Celsius) 25.0°C FAST Direct Reading with Standards ppm AMMONIA OFF 10.00 x 10–7 9.99 x 1010 All parameters ON All parameters ON All parameters ON MANUAL AUTO, One Point LOG DATA X.X C (Celsius) FAST OFF 0.00 600.00 % Sat MANUAL mg/L 2.0 1.0 2.0 1.0 mg/L 1 1 1 for OUR; 15 for SOUR 5 2 1 (SOUR only) XL15 XL20 XL25 XL30 XL40 XL50 XL60 ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● OUR (SOUR) 165 Appendix: XL Series Meters Factory Default Settings XL15, 20, 25, 30, 40, 50 and 60 meters Screen Display Configuration COND / RES / TDS / SAL Setup Modes Print Configuration Data Configuration Sample ID Calibration Points Print Interval Stable Indicator Cell Constant Temperature Units Default Temperature Reference Temperature Temperature Coefficient Alarm Limits Conductivity Standards COND Standard Recognition Alarm Limit Low Alarm Limit High RES Alarm Limit Low Alarm Limit High TDS Factor Alarm Limit Low Alarm Limit High SAL Alarm Limit Low Alarm Limit High Default Setting All parameters ON All parameters ON All parameters ON MANUAL Single Point LOG DATA ON 1.000/cm C (Celsius) 25 degree Celsius 25 degree Celsius 2.100% per degree OFF 84 uS, 1.413 mS, 12.88 AUTO 0uS 500000uS 3.000 Ohm 100.000 MOhm 0.60 0 ppm 300000 ppm 0.000 ppt 90.000 ppt XL15 XL20 XL25 XL30 XL40 XL50 XL60 ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● TDS 166 Appendix: XL Series Meters Print Function XL15, 20, 25, 30, 40, 50 and 60 meters Kindly note that the XL meter functions only with printers that features PCL 5e (printer command language 5 enhanced) language. Host-based printer with PCL 5e language relies on the computer’s processor to generate printable pages. Non PCL 5e language printer triggers XL meter to modify its internal register and can cause the meter to crash. The XL series meter allows you to send data to the selected PCL 5e Laser or HP LaserJet 1022n through the USB-A port located at the back panel of the XL series meter. To print using USB-A 1. Power on the XL Series meter and go to single measurement mode. 2. Connect HP printer to USB-A port on the back of the XL Series meter. 3. Enter Sample ID. 4. Tap Log data Icon. 5. On the Measure screen, touch Print to initiate the print function. 6. The Print dialog box is displayed on the screen. 7. Select the correct printer using the Printer drop down box selection. 8. Set the Port drop down box selection to LPT1. 9. Make all other selections as needed and then touch OK to start sending data. Print icon will appear only in single channel measurement mode. When a HP 1022 printer is connected to XL Series meter, you can select either PCL Laser or HP LaserJet 1022n and port LPT1 from the print dialog box as shown in above diagrams. 167 Appendix: XL Series Meters Print Function XL15, 20, 25, 30, 40, 50 and 60 meters To print using IrDA (Infrared) port 1. Power on the XL Series meter and go to single measurement mode. 2. Align the IrDA port on the back of the XL Series meter with the IrDA port on the printer to establish link. 3. On the Measure screen, touch Print to initiate the print function. 4. The print dialog box is displayed on the screen. 5. Select the correct printer using the Printer drop down box selection. 6. Set the Port drop down box selection to IrDA. 7. Make all other selections as needed and then touch OK to start sending data. Ensure that the Draft Box in the Print dialog box is always checked to avoid improper printing. NOTE: The XL meter should be powered on and be in the measurement mode before the printer is connected to it. 168 Appendix: Determining Isopotenial Points Experimentally Appendix: Background and Text Color Adjustment XL 15, 20, 20, 25, 50 andandmeters XL15, 25, 30, 40, 50 60 60 meters The Display Color Setting option in System Setup allows you to customize the background and text color that you would like to be displayed on the screen. To set the background and text color: Touch the System Setup button to access the Display Color Setting box. Touch the Default Color button to select the default display color settings for the reading display screen. Touch the Custom Colors button to adjust the background and text color to be displayed on the screen. Touch the My Favorites button to select color setting from your Favorites list. Functions buttons on Custom Display Color Setting Screen: Touch the Adjust Background Color to define the background color for your screen from the Basic colors box. Touch the Adjust Text Color to select the color of the text from the Basic colors box. Once you have defined the color you want, Touch Apply & Close button to apply the selected settings. Touch the Add to Favorites button to include current selected background and text color into your Favorites list. Touch Back button to go to System Setup box. See next page to assign name to your setting and to select setting from My Favorites list. 169 Appendix: Determining Isopotenial Points Experimentally Appendix: Background and Text Color Adjustment XL 15, 20, 20, 25, 50 andandmeters XL15, 25, 30, 40, 50 60 60 meters To assign name to your background and text setting and to include it into your My Favorites list From the Custom Display Color Setting Screen, touch the Add to Favorites button to assign name to your selected background and text color. Type a name for your current selected background and text color and touch Enter to include it into your My Favorites list. The assigned Setting ID will be listed in My Favorites Color Setting box. Functions buttons on My Favorites Color Setting Screen My Favorites Color Setting box displays all the background and text settings that have been saved by the user. To select setting from Favorites list tap My Favorites button. Click the Setting ID that you want to use from the My Favorites Color Setting box and tap Apply & Close button to apply the settings. To delete setting from the Favorites list, click the Setting ID and tap Delete Setting button. Touch Back button to go to System Setup box. 170 Appendix: Determining Isopotenial Points Experimentally XL15, 20, 25, 50 and 60 meters The isopotential point of an electrode system is the point at which electrode potential is unaffected by a change in temperature. The coordinates of this point would be reported as (pXiso , Eis0 ). For an ideal system, this point would be coincident with the system’s Zero Potential Point (pXiso , E0 ). In practical systems, however, this coincidence rarely occurs, and for some systems, there is no true Isopotential Point but a general Isopotential area. If a system exhibits an apparent Isopotential Point, or at least an Isopotential area with relatively small spread, Isopotential coordinates may be established and possibly used to some advantage. Isopotential correction may be used only in conjunction with a One- or Two- Point Standardization; it is required only when both accuracy over a significant temperature range as well as operation with an asymmetric electrode system are contemplated. However, Isopotential correction is never necessary if all measurements will be performed on samples which are at similar temperatures. Most conventional pH electrode systems are designed and manufactured to be highly symmetrical cells. Consequently, for most pH work, unless ultimate accuracy over broad temperature ranges is required, Isopotential may be ignored. Specifically, this is accomplished by setting the Isopotential at its reset value of zero millivolts. The following is an example for determining an Isopotential Point: Data points are first established for three different standards at three different temperatures. The data points are then plotted and will produce three isotherms which should resemble the plot in either figure 1 or figure 2. In figure 2, the Isopotential Point is well defined as the intersection point of the three Isotherms (pX so , E iso ). The Isopotential Point is not so well defined in figure 1, but a value may be interpolated with some accepted error. 171 Appendix: pH Theory XL15, 20, 25, 50 and 60 meters Since its introduction by the Danish chemist Sorensen in 1909, pH measurement has become one of the most commonly used and important measurements in both laboratory and industrial settings. pH measurement and control is vital to a wide array of endeavors including municipal and industrial wastewater treatment, and textile, pharmaceutical, food, and petroleum production. Even our very existence itself is dependent upon pH. Most organisms can exist only within a narrow pH range. In humans, for example, the pH of blood must be maintained within the pH range of 7.3 to 7.4. In general, pH is a measure of the degree of acidity or alkalinity of a substance. It is related to the effective acid concentration ("activity") of a solution by this defining equation: pH = -log aH3O+ with a H3O+ representing the activity or effective concentration of the hydronium ion in solution. Analysts traditionally work with concentration units rather than activity. Therefore neglecting activity, pH can be defined by the following equation: pH = -log [H3O+] with [H3O+] representing the concentration in Moles/liter of the hydronium ion in solution. The pH range includes values from 0 to 14. Values from 0 to 7 represent the acidic half of the scale. Values from 7 to 14 represent the alkaline or basic half of the scale. The pH value 7 is considered neutral, as it is neither acidic or alkaline. The pH scale is based on the dissociation constant of water. Water, even in its purest state, dissociates as follows producing a positively charged hydronium ion (H3O+) and a negatively charged hydroxyl ion (OH-): 2H2O = H3O+ + OH– 172 Appendix: pH Theory XL15, 20, 25, 50 and 60 meters At 25°C in pure water, the concentration of hydronium ions is extremely small, 1 x 10-7 Moles/liter, and balanced by an equal concentration of hydroxyl ions. The equilibrium constant, Kw of water is the product of the hydronium ion and hydroxyl ion concentrations: Kw = [H3O+] [OH–] = [1x10-7] [1x10-7] = 1x10-14 Since the hydronium ion concentration is 1 x 10-7 Moles/liter, the pH of pure water is 7 , the neutral pH, as stated above: pH = -log [1 x 10-7] = 7 In aqueous solutions at 25°C, the product [H3O+] [OH–] or the Kw of water must remain constant. Therefore, an increase in concentration of either term, [H3O+] or [OH–], will result in a decrease in the other. For example, if a strong base, sodium hydroxide (NaOH) is added to water to the extent that its final concentration is 0.01 Moles/liter, the concentration of the OH– ion is 0.01 Moles/liter, and the concentration of the H3O+ must decrease according to the Kw equation as follows: [H3O+] = Kw/ [OH–] = 1 x 10-14 / 1 x 10-2 = 1 x 10-12 The pH of this solution is: pH = -log [1 x 10-12] = 12 This high pH indicates that the 0.01 M NaOH solution is strongly alkaline; the concentration of hydronium ions is extremely small. 173 Appendix: pH Theory XL15, 20, 25, 50 and 60 meters pH Measurement The pH value of a sample can be determined in several ways. These include the use of organic dyes which change color in certain pH ranges. The dyes can be added directly to the solution or impregnated onto paper which may be dipped into the solution. At best, these "colorimetric" methods yield approximate pH values, often with an accuracy of plus or minus 0.5 pH units. The preferred and most accurate way to measure a pH value is the potentiometric measurement, using a pH electrode, a reference electrode, and a pH meter. This method is based on the fact that certain electrodes, immersed in solution, produce a millivolt potential (i.e. voltage ) that is related to the hydronium ion concentration or pH of a solution in a precise way. The relationship between the electrode's voltage and the solution pH is defined by the Nernst equation: Emeas = E* – ( 2.3RT ) nF (pH) In this equation, Emeas is the voltage output of the electrodes, E* is the total of all other voltages in the system including the reference voltage, R is the Gas Law constant, T is the temperature in °Kelvin, n is the charge on the hydronium ion (+1), and F is the Faraday constant. pH Meter The pH meter is a sensitive voltmeter capable of accurately measuring small voltage differences between the pH electrode and the reference electrode. This voltage difference is amplified, and shown as a pH reading. Almost all modern meters are microprocessor controlled, and programmed to use electrode voltages, efficiency, and temperature to calculate an accurate pH for the sample. Since the voltage output from different electrodes will vary, it is essential to calibrate a pH meter. The ability to calibrate or to standardize a pH meter permits the meter to match the pH reading on the meter with the known pH value of a buffer solution. For best accuracy, it is recommended that at least two buffer solutions be used to calibrate a pH meter. Buffer solutions are available as ready-to-use solutions, concentrated solutions, capsules, or prepackaged salts. The following table lists three of the most widely used NIST buffers along with their pH values at different temperatures. Temperature (C) 0 10 20 25 30 40 50 4.01 4.003 3.998 4.002 4.008 4.015 4.035 4.060 6.86 6.984 6.923 6.881 6.865 6.853 6.838 6.833 9.18 9.464 9.332 9.225 9.180 9.139 9.068 9.011 174 Appendix: pH Theory XL15, 20, 25, 50 and 60 meters pH Electrodes The electrode system consists of two half cells: a pH indicating electrode, which is primarily responsive to the acidity (the hydronium ion concentration-tion) of a solution, and a reference electrode, which provides a constant voltage and completes the electrical circuit. Traditional pH indicating electrodes use a tip made of pH sensitive glass. Inside this electrode is a buffer solution with a fixed pH and ionic strength. A silver wire coated with silver chloride is immersed inside this internal solution, and establishes electrical contact between the solution and the meter. The voltage associated with this wire and the voltage associated with the pH of the internal solution and the inside wall of the pH sensitive glass tip remain constant. Therefore, changes in voltage from this electrode result from the voltage developed between the solution and the outside of the glass tip. If the pH sensitive glass tip or membrane is to function properly, it must be hydrated. A dry or dehydrated electrode membrane will not respond properly to changes in acidity. pH electrodes are also effected by changes in temperature, and the presence of other ions. Temperature effects can be countered by temperature compensation functions on the pH meter. While temperature compensation will not allow you to predict what the pH of the sample is at another temperature, it will permit you to accurately assess the pH at whatever temperature you are presently working. pH sensitive membranes are also sensitive, though to a lesser extent, to other ions than the hydronium ion. For example, most pH glasses are somewhat sensitive to sodium ion as well. For some pH glasses, this means an error as high as 0.5 pH units in highly alkaline, high-sodium solutions. The special FS-5 glass used in Fisher's pH electrodes exhibits much less sodium error in these solutions, <.05 pH units. Reference electrodes typically consist of three elements: an internal reference electrode, a filling solution, and a reference junction through which the filling solution can "flow", and provide electrical contact with the sample and the internal reference electrode. The most convenient internal reference electrodes are made from a metal (such as silver or mercury) and its sparingly soluble salt (silver chloride or mercurous chloride). The filling solution is most often a concentrated solution of potassium chloride. Most problems with reference electrodes are associated with the interruption or blockage of flow of the potassium chloride fill solution through the reference junction. The classic electrode pair, separate pH indicating and reference half cells, offer you unmatched versatility to match the needs of your sample. This approach makes for the highest accuracy, as well as low replacement costs, since usually only one of the pair is broken or malfunctioning. However, the pH indicating half-cell and the reference half-cell can be merged into one electrode: a combination electrode. Combination electrodes are quite popular for they offer distinct advantages in convenience and compactness. Some combination electrodes also incorporate an ATC probe into their body also, providing temperature readout and compensation with meters equipped with these features. Newer combination electrodes are available in which the glass pH membrane sensor has been replaced with a field effect transistor or FET. All of Fisher Scientific's AB, AR and XL meters are capable of using this type of electrode by direct connection (except AB30). 175 Appendix: ISE Theory XL25, 50 and 60 meters Ion selective electrodes (ISE) respond to ionic activity or concentration in a liquid because of the characteristics of the electrode’s sensing membrane. Ideally, the ISE develops an electrical potential which is proportional to the activity or concentration of the ion for which the membrane is selective. For example, the fluoride electrode can be used to directly sense fluoride ion in drinking water. Analyses utilizing ion selective electrodes offer the advantages of speed, ease-ofoperation, low cost, and versatility over other analytical techniques. The ISE can measure the ion concentration of samples at very high levels ( > 1000ppm ) to very low levels ( < 1ppm ). When an ISE, the indicator electrode, and a reference electrode are placed in a solution, and connected to a pH/mV/ion meter, they form a potentiometric cell. At equilibrium, the meter measures the potential difference between the ISE and the reference electrode. This millivolt potential is proportional to the activity of the ion of interest, and the relationship is defined by the Nernst equation: E = E* ±2.3 RT (log a) nF E is the measured potential E* is the sum of the standard potential and all other constant potentials of the system R is the gas constant T is the temperature in °K F is Faraday’s constant n is the valence of the ion being measured Activity, a, is not the same as concentration. It is a thermodynamic function whose value is influenced by the ionic environment in which the ion exists. Activity and concentration are the same in very dilute, ideal solutions. In non-ideal solutions, activity and concentration are related by an “activity coefficient“. ISEs sense the activity of free, uncomplexed ions rather than concentration. However, by calibrating the meter with standards with a similar ionic back-ground as the sample, the difference between activity and concentration becomes negligible. Most often this is achieved by adding an ionic strength adjustor to both samples and standards. The Nernst equation becomes: E = E* ±2.3 RT (log c) nF where where c is the concentration of the ion of interest. 176 Appendix: ISE Theory XL25, 50 and 60 meters This form of the Nernst equation states that the electrode potential varies directly with the log of the concentration in straight line manner, and results are then expressed in the preferred concentration units. The slope of the line is equal to the value of: Slope = S = 2.3RT/nF The table below gives theoretical slope values at 25°C. Species Monovalent cation Monovalent anion Slope (mV/decade) +59.16 -59.16 Species Divalent cation Divalent anion Slope (mV/decade) +29.58 -29.58 The Nernst equation thus reduces to: E = E* + S [log c] Ion-selective Analysis Methods Direct Analysis In this method, a sample concentration is determined by measuring the electrode potential and comparing to those obtained in standard solutions. Normally, an ionic strength adjustor and/or pH adjustor must be added to both the samples and the standards. This helps in that the closer the standard solution matrix is to the sample matrix, the more valid is the analysis. A number of standard solutions are used to standardize a pH/mV/ion meter, or to construct a calibration curve (by plotting the electrode’s output in mV versus the log of the concentration). The sample concentration is then read from the meter or the calibration curve. The advantages of the direct method of analysis are: 1. Many samples (particularly those with relatively simple ionic backgrounds) can be quickly measured after a single calibration procedure. 2. The technique is valid over a wide range of concentrations. 3. Sample volume values are not required, and may also vary over a wide range. 177 Appendix: ISE Theory XL25, 50 and 60 meters Incremental Methods These procedures can reduce errors caused by temperature variations, complex matrices, and complexation. They are also useful for applications where only occasional samples are analyzed. Incremental methods include: Known Addition, Known Subtraction, Analyte Addition, and Analyte Subtraction. Known Addition and Known Subtraction With the Known Addition and Known Subtraction methods, the initial millivolt output of the electrode in the sample solution is measured. Then an aliquot of standard solution is added, and a final millivolt potential is measured. The concentration of the sample can then be computed from the observed change in the millivolt readings before and after the addition. The techniques differ in that with Known Addition the standard added is the same ionic species as that being measured. With Known Subtraction, the measured ion is not the same as the one being added via the standard. For example, a chloride ISE can be immersed in sample for a chloride measurement. If a silver standard is added to the sample, AgCl precipitates, effectively removing or subtracting chloride ion from the sample. Equations for known addition and known subtraction calculations are as follow: Known Addition Cs= C std V std___ (Vs + Vstd )10∆E/S – Vs C std V std____ Vs – (Vs + Vstd )10∆E/S Known Subtraction Cs= where Cs is the concentration of the sample; Cstd is the concentration of the standard; Vs is the sample volume; Vstd is the standard volume; ∆E is the difference in millivolt readings from the electrode; and S is the slope of the electrode determined in a previous standardization. Whereas the direct method is suitable for samples with fairly uncomplicated ionic matrices, the addition methods are advantageous with samples that have complex matrices, samples in which no ISA is added, samples in which excess complexing species are present, and samples whose concentration is in the non-linear region on the electrode response curve. 178 Appendix: ISE Theory XL25, 50 and 60 meters Analyte Addition and Analyte Subtraction In the Analyte methods, the initial millivolt reading is taken with the electrode immersed in the standard; then an aliquot of sample is added, and the final millivolt reading is taken. Sample concentration is calculated from the change in the millivolt readings. As with known addition, with analyte addition the sample and the standard solution contain the same ion being measured. With analyte subtraction, the ion being measured is in the standard solution, and not in the sample solution. For example, a fluoride standard and a fluoride ISE might be used to measure to aluminum concentration of a sample. When the sample containing aluminum is added to the standard it reduces the measured fluoride content of the standard. The amount of reduction is proportional to the aluminum in the sample. The analyte methods offer the same advantages as do the addition methods in that they effectively deal with complex samples. A distinct advantage of the analyte subtraction method is that it can be used in cases where an ISE does not exist for a given species, such as aluminum in the example cited. 179 Appendix: DO Theory XL40 and 60 meters Meter Operation The XL40 and XL60 meter uses the polarographic method of determining dissolved oxygen concentration. A voltage is maintained across two electrodes (a gold cathode and a silver anode) and an electrolyte separated from the sample solution by an oxygen permeable membrane. Oxygen diffuses from the sample across the membrane where it is reduced at the cathode. 1) O2 + 2H2O + 4e- —> 4OHThe current generated, I, by such an electrode is proportional to the oxygen concentration of the sample. The rate of oxygen reduction at the cathode is significantly faster than the rate of diffusion to the electrode. Therefore, the rate of oxygen reduction is diffusion limited 2) I = kD (O2) I is the measured current k is a proportionality constant D is the diffusion coefficient of oxygen Equation 2 is a simplified description of current generated by the oxygen electrode. Many other factors such as electrode surface area, membrane thickness, membrane permeability coefficient, and oxygen partial pressure are integral to this process and incorporated into the constants k and D. As the partial pressure of oxygen in the water is equal to that in the atmosphere, the oxygen partial pressure differential between the sample and the electrolyte inside the electrode is the driving force bringing oxygen to the electrode. Oxygen Solubility Oxygen solubility in water is critical parameter in many arenas including biochemistry, industrial processes, and particularly environmental science and engineering. sufficient dissolved oxygen is an absolute requirement for good water quality. It is essential for aerobic life and the natural purification processes to which they contribute. Dissolved oxygen concentrations below 5 ppm will result in substantial damage to the aquatic ecosystem, and concentrations below 2 ppm can result in fish kills and growth of harmful bacteria. The ultimate amount of oxygen possible in water is a function of temperature, atmospheric pressure, and the concentration of dissolved salts or salinity. At a given atmospheric pressure, water will hold a fixed, well-defined amount of oxygen at a given temperature. Water at higher temperatures will hold less oxygen than water at lower temperatures. Dissolved salts in water lower its capacity for oxygen. Though the amount of oxygen that water can hold is reduced by the presence of dissolved salts, the partial pressure of the dissolved oxygen still equals that of oxygen in the air above it. The XL40 and XL60 meter compensates for this fact by relating the salinity value of water to its true capacity for oxygen at a given temperature and pressure. Biochemical Oxygen Demand (BOD) The BOD test measures the degree to which water is contaminated with organic material, which is decomposed by aerobic bacterial processes. This test is a critical importance for municipal and industrial discharges. Typically, the sample is diluted with oxygen saturated water. The dissolved oxygen content is measured immediately after dilution, and after a 5-day incubation period. The BOD is expressed as the mg/L of dissolved oxygen consumed during the incubation. 180 Appendix: Replatinization XL20, 30, 50 and 60 meters Replatinization is the process of replacing the platinum on the surfaces of the 2 cell conductivity probes that may flake or wear off over time. The platinum on the surface of the probe is used to increase the surface area of the measuring surface resulting in decreased polarization error. Replatinization is a relatively quick procedure to perform, taking no more than 5 minutes. Although replatinization is not a long process, the replatinization solution is costly. If you are not certain that replatinization will improve the performance of your accumet conductivity probe, please call the technical support hotline at 1-888-358-4706. To Perform Replatinization 1. Access the Replatinization mode from the Mode screen. In any measuring mode, touch Mode to access the Mode screen. 2. Touch Replat. to enter the Replatinization mode. 3. Immerse your 2 cell conductivity probe into the replatinization solution. The immersion depth should be enough to cover the vent holes on the probe. 4. Touch Start on the display screen to begin the process of replatinization. At this time a countdown timer will appear on the display screen showing the time elapse and time remaining in the replatinization procedure. Note: At anytime after you have initiated the replatinization: You can touch Stop to stop the procedure OR You can touch Exit to cancel the replatinization the procedure and return to the Mode screen. 4-cell conductivity probes do not require replatinization. 181 Appendix: Conductivity Theory XL20, 30, 50 and 60 meters Conductance is a quantity associated with the ability of primarily aqueous solutions to carry an electrical current, I, between two metallic electrodes when a voltage E is connected to them. Though water itself is a rather poor conductor of electricity, the presence of ions in the water increases its conductance considerably, the current being carried by the migration of the dissolved ions. This is a clear distinction from the conduction of current through metal, which results from electron transport. The conductance of a solution is proportional to and a good, though nonspecific indicator of the concentration of ionic species present, as well as their charge and mobility. It is intuitive that higher concentrations of ions in a liquid will conduct more current. Conductance derives from Ohms law, E = IR, and is defined as the reciprocal of the electrical resistance of a solution. C = 1/R C is conductance (siemens) R is resistance (ohms) One can combine Ohms law with the definition of conductance, and the resulting relationship is: C = I/E I is current (amps) E is potential (volts) In practice, conductivity measurements involve determining the current through a small portion of solution between two parallel electrode plates when an ac voltage is applied. Conductivity values are related to the conductance (and thus the resistance) of a solution by the physical dimensions - area and length - or the cell constant of the measuring electrode. If the dimensions of the electrodes are such that the area of the parallel plates is very large, it is reasonable that more ions can reside between the plates, and more current can be measured. The physical distance between the plates is also critical, as it effects the strength of the electric field between the plates. If the plates are close and the electric field is strong, ions will reach the plates more quickly than if the plates are far apart and the electric field is weak. By using cells with defined plate areas and separation distances, it is possible to standardize or specify conductance measurements. Thus comes the term specific conductance or conductivity. The relationship between conductance and specific conductivity is: 2 Specific Conductivity, S.C. = (Conductance) (cell constant, k) = siemens * cm/cm = siemens/cm C is the Conductance (siemens) k is the cell constant, length/area or cm/cm2 Since the basic unit of electrical resistance is the ohm, and conductance is the reciprocal of resistance, the basic unit of conductance was originally designated a “mho“ - ohm spelled backwards - however, this term has been replace by the term “siemen“. Conductivity measurements are reported as Siemens/cm, since the value is measured between opposite faces of a cell of a known cubic configuration. With most aqueous solutions, conductivity quantities are most frequently measured in microSiemens per cm (µS/cm) or milliSiemens per cm (mS/cm). The accumet XL20,30,50 and 60 meter not only measures conductivity readings from micro or milli Siemens but also reads resistivity (Ohms, kOhms and MOhms), TDS (ppm and ppt), and salinity (ppt). 182 Appendix: Conductivity Theory XL20, 30, 50 and 60 meters The salinity scale which ranges from 0 to 90 ppt is a measure of all salts, not just sodium chloride. This scale was originally devised for seawater, and is based on seawater at 15 degrees Centigrade has a conductivity equivalent to that of a potassium chloride solution of a known concentration. This solution (0.44 molal) is defined as having a salinity of 35 ppt. Note: ppm = parts per million, ppt = parts per thousand, 1000 ppm = 1 ppt The total dissolved solids scale approximates the ppm TDS in surface waters by multiplying the conductivity of a sample by a factor, 0.66. Some users prefer the use of resistivity units to describe their water, particularly where high purity water is involved. The unit most often used to describe resistivity is megohm•cm., which is simply the reciprocal of conductivity (µS/cm). The chart below shows the relationship between these units. Conductivity, µS/cm 0.056 0.1 1.0 2.5 10.0 Resistivity, megohm. cm 18.0 10.0 1.0 0.4 0.1 Conductivity Measurement accumet conductivity electrodes consist of glass or epoxy bodies in which platinum or platinized sensing elements are fixed. Typically, each electrode has two such sensing elements and are designated two-cell electrodes. The previous discussion has focused on this type of electrode. Four cell electrodes are also available, and the theory and application of these are in a separate section. These sensors contact the solution whose conductivity value is sought. The exact cell constant of the electrode must be determined prior to measuring the sample. In essence, this is accomplished by fixing the nominal cell constant of the electrode into the meter, and recording the observed conductivity value associated with a standard conductivity solution (usually a KCl solution) with a precisely known value. The following calculation yields the actual cell constant. k = standard value of solution (µS) / observed value of solution (µS) Fortunately, the accumet XL20, 30, 50 and 60 meter automatically does this calculation for you by touching Standardize. To produce an appropriate current signal for the meter it is important to choose an electrode with an appropriate cell constant. The following table lists the optimum conductivity ranges for electrodes with cell constants of 0.1, 1, and 10. Cell Constant 0.1 1.0 10.0 Optimum Conductivity Range, 2-cell 0.5 to 200 µS/cm 0.01 to 2 mS/cm 1 to 200 mS/cm Prior to use the electrodes should be conditioned in distilled or deionized water for at least 10 minutes or in accordance with the manufacturer’s instructions. 183 Appendix: Conductivity Theory XL20, 30, 50 and 60 meters The four-cell electrode Traditionally, conductivity measurements were made with a “two cell“ electrode. This electrode used two metallic sensors, and anode and a cathode to which ions migrated. Under the influence of DC current, the electrodes quickly became polarized. In this situation, molecules formed at the electrode surfaces and ions migrating to the area collect around the respective anode or cathode and actually screen it from other ions. In essence the flow of ions stops, and current ceases to flow. Polarization and associated errors can be minimized by using AC voltage, the appropriate cell constant, and a large electrode surface area. The influence of polarization can also be minimized by the use of a four-cell electrode. The four cell configuration consists of two cells, and outer cell and an inner cell. Voltage is applied to the sensors of the outer cell, which in turn generates a voltage across the sensors of the inner cell. The inner cell is connected to a high impedance circuit and, unlike the outer cell generates no current. Since no current is generated across the inner cell, polarization cannot occur at the inner cell. By measuring the voltage of the inner cell, which is adjusted to match the reference voltage by increasing or decreasing the current through the inner cell, one obtains a true picture of conductivity minus the influence of polarization. Cell Constant 0.1 1.0 10.0 Optimum Conductivity Range, 4-cell Not Available 0.01 to 20 mS/cm 1 to 200 mS/cm Conductivity and Temperature Conductivity in aqueous solutions reflects the concentration, mobility, and charge of the ions in solution. The conductivity of a solution will increase with increasing temperature, as many phenomena influencing conductivity such as solution viscosity are affected by temperature. The relationship between conductivity and temperature is predictable and usually expressed as relative % change per degree centigrade. This temperature coefficient (% change per degree) depends on the composition of the solution being measured. However, for most medium range salt concentrations in water, 2% per degree works well. Extremely pure water exhibits a temperature coefficient of 5.2%, and concentrated salt solutions about 1.5%. Since temperature effects the conductivity measurement so profoundly, the usual practice is to reference the conductivity to some standard temperature. This is typically 25°C, but the XL20, XL30, XL50 and XL60 meters lets the operator select any value between of 15°C and 30°C in the Setup menu option, set Reference Temperature. The XL20, XL30, XL50 and XL60 meters permits you to enter the temperature coefficient which best suits your sample and use an ATC probe to automatically temperature compensate back to the chosen reference temperature. Refer to the Setup menu option, set Temperature Coefficient. 184 Replacement Parts Replacement Parts Description Fisher Catalog Number accuCap™ refillable electrode, double junction, glass body........................................ 13-620-130 Replacement filling solution for 13-620-130 electrode ................................................. 13-636-430 accumet pH combination electrode, single junction, Ag/AgCl reference, glass body, BNC connector ............................................................................................................. 13-620-285 ATC Probe ...................................................................................................................... 13-620-19 accuFlex electrode support arm and base ................................................................... 13-637-671 BNC Shorting cap ........................................................................................................... 13-620-99 pH Accessories pH Electrode Fisher Catalog Number accuCap Glass Body Gel-Filled pH Combination Electrode ........................................ 13-620-131 accuCap Plastic Body Gel-Filled pH Combination Electrode ...................................... 13-620-132 accuCap Glass Body Spear Tip pH Combination Electrode ........................................ 13-620-133 accumet 3-in-1 pH/ATC combination electrode, single junction, Ag/AgCl reference, epoxy body, BNC connector......................................................................................... 13-620-530 accumet 3-in-1 pH/ATC combination electrode, Tris-compatible, calomel reference, epoxy body, BNC connector......................................................................................... 13-620-531 accuFet XL cone-tip electrode...................................................................................... 13-620-700 accuFet XL cup-tip electrode........................................................................................ 13-620-710 accuFet XL flat-tip electrode......................................................................................... 13-620-720 accuFet XL lance-tip electrode. .................................................................................... 13-620-730 Calibration Certificate pH Buffers and Solutions pH 4.00 7.00 10.00 4.00 7.00 10.00 Color Red Yellow Blue ---Description / Ingredients Potassium Biphthalate Potassium Phosphate Monobasic Potassium Carbonate, Potassium Individual Tear Open pH Packets Individual Tear Open pH Packets Individual Tear Open pH Packets Size 500 mL 500 mL 500 mL 20/box 20/box 20/box Fisher Catalog Number SB101-500 SB107-500 SB115-500 13-300-150 13-300-149 13-300-148 Fisher Catalog Number NIST pH meter calibration certificate.............................................................................. 15-094-28 Fisher BufferPac® (pH 4.00, 7.00, and 10.00 buffers), 3 x 500 mL...................................... SB105 Individual Tear open pH Packets assortment (5 each of pH 4.00, 7.00, 10.00 and rinse packets), 20/box .................................................................................................. 13-300-147 Electrode Rinse Individual Tear open pH Packets, 20/box .......................................... 13-300-180 Electrode storage solution, 1 L ............................................................................................ SE40-1 To place an order, call 1-800/766-7000, fax 1-800/926-1166, or online www.fishersci.com 185 Replacement Parts Dissolved Oxygen Accessories Description Fisher Catalog Number Self-stirring probe ........................................................................................................... 13-620-SSP DO probe membrane kit, includes 6 replacement caps, polishing disk and electrolyte filling solution..................................................................13-637-DOM Electrolyte filling solution, 500 mL ................................................................................ Na2SO4,KCL 0% zero oxygen calibration solution, 500 mL..................................................................... 00653-00 Adapter, for adapting YSI model 5910 probes to accumet benchtop meters ........ 13-637-DOADPT Adapter, for adapting YSI model 5905 probes to accumet benchtop meters (also requires adapter 13-637-DOADPT).......................................................................... 13-299-78 BOD Accessories BOD bottles with robotic stoppers, unnumbered, 300 mL, case of 24 .............................. 02-926-26 BOD bottles with pennyhead stoppers, unnumbered, 300 mL, case of 24 .......................02-926-7A Polyseed BOD capsules, pack of 50 ............................................................................... 02-297-200 Polyseed-NX BOD capsules, pack of 50......................................................................... 02-297-201 To place an order, call 1-800/766-7000, fax 1-800/926-1166, or online www.fishersci.com 186 Replacement Parts Conductivity Accessories Description Fisher Catalog Number Conductivity probe storage solution. Keeps probes ideally conditioned and ready for use...............................................................................................................09-330-1 accumet Immersion Type Conductivity Electrodes Cell constant 0.1 cm 1.0 cm -1 -1 -1 2 Cell Conductivity Cell Glass Body — — — Epoxy Body 13-620-101 13-620-100 13-620-102 4 Cell Conductivity Cell Glass Body — 13-620-163 13-620-164 Epoxy Body — 13-620-165 13-620-166 10.0 cm accumet Conductivity Calibration Standards Conductivity 10 µmhos 100 µmhos 1000 µmhos 1413 µmhos 10,000 µmhos 100,000 µmhos Resistivity 0.1 megohms 0.01 megohms 0.001 megohms 0.0007 megohms 0.0001 megohms 0.00001 megohms Dissolved Solids 6.6 ppm 66 ppm 660 ppm 933 ppm 6600 ppm 66,000 ppm 16 oz bottle 09-328-1 09-328-2 09-328-3 09-328-11 09-328-4 09-328-5 100mLx6 bottles 09-328-6 09-328-7 09-328-8 09-328-12 09-328-9 09-328-10 For a complete selection of electrodes and accessories, please refer to the Fisher Catalog, or contact your Fisher Scientific sales representative. To place an order, call 1-800/766-7000, fax 1-800/926-1166, or online www.fishersci.com Note: For electrochemistry technical support, call 1-888-358-4706 or e-mail accumet@thermofisher.com 187 Replacement Parts For more information on Eutech Instruments products, contact your nearest Eutech Instruments distributor or visit our website listed below: Manufactured by: Eutech Instruments Pte Ltd Blk 55, Ayer Rajah Crescent, #04-16/24 Singapore 139949 Tel: (65) 6778 6876 Fax: (65) 6773 0836 E-mail: eutech@thermofisher.com Web-site: www.eutechinst.com Distributed by: 68X374204 Rev 6 Dec 07 188 ...
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This note was uploaded on 01/06/2011 for the course CHEM 223 taught by Professor Scheeline during the Fall '08 term at University of Illinois at Urbana–Champaign.

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