Experiment 1 Report Measurement of DC Current & Voltage -...

Unformatted text preview:7 ~ v—r—w vwr-w,' r"! w I? Experiment One: Measurement of DC Current and Voitage Engr. 361, Section 1 Formal September/900% September/ 1 6/20 1 3 I u I r I,, Table of Contents Abstract Report -Introduction -Body -Results -Conclusions -References Abstract The general idea behind this lab was to understand the working of an ammeter and voltmeter. The voltmeter is actually constructed and used to do parallel voltage readings, while the ammeter is provided and set up in series to also do readings. There are two main parts to this lab and they will be indulged to a much greater extent now. Lab one was an ideal lab for the student looking to understand the theory behind and also be able to wire up a voltmeter. However, the constructed voltmeter isn't ideal because it is in practice not theory. The overall goal of this lab was to gain knowledge on these basic electrical tools and to understand the challenges encountered while using them. The student first took to pen and paper to find the theoretical voltage and current values of the circuit to be studied. These values were helpful in the analysis of the data measured at the "end of the day". The tools used in this lab are as follows: B&K Precision model 1623A variable dc power supply, DC milli-ammeter(0-50mA), DC micro—ammeter(0-50microA), Decade resistance box, Circuit board, and 8 resistors ranging from 2000hms to 200kohms. Part I-VI Part I and II of this lab were there to help with the understanding and theory needed for any good engineer or scientist. The first part was specifically designed around the ammeter, while the second was about the voltmeter. Both of these are basic but very powerful electrical tools. The ammeter measures currents and is connected in series; the voltmeter measures voltages and is connected in parallel. One question that must always be raised with electrical components is the idea of having an ideal component or as 01086 to ideal as can be realized in actual practice. Part III deals with the actual design of the voltmeter and the measurement of resistance Rm. As stated before, this component is connected in parallel, and it measures the actual voltages across resistors etc. A circuit is wired as in Figure three of the lab to be able to find the internal resistance Rm. This Rm is then used with the 50xlO"(-6)A to find the voltage drop across the meter. This value, in this case, of l.04v drop is subtracted from 25 volts full deflection required. Finally, this value is used to help find Rs which is the resistor in series with the meter movement. In Part IV, the student does preliminary work on paper to find all values in theory. The next step was to reinforce and check that knowledge by using multisim to realize the circuit in question. Part V of this lab was and is there to help the student actually see and analyze the circuit. He or she may take what that they knew in theory/ on paper, and they may now apply that knowledge to analysis. After all, what good is theory if you are never actually wire up a circuit and use it for some said purpose? The circuit in Figure five is wired, and it is then analyzed to find voltages and currents across resistors and multiple resistor combinations. Part V1 is written out along with the circuit analysis for part IV; they are attached along with other important information. Results Tables that record the results of voltages currents and the comparison of those are attached here after. Error analysis is ( ([theory-measuredl)/theory)* 100. Here is an example taking into account the theory and measured values ((l10.01-10|)/10.01)*100= .09%. Another calculation was made using ohm's law V=IR or more specifically Voltage drop=(50EE-6)*(20999ohms)=1.04volts. The calculation of Rs was also completed using ohm's law R=V/l which is Rs=23.95v/50EE-6A=479Ekohms. Conclusions As stated before, the purpose of this lab is to help with analysis, wiring, and finally checking the results of a circuit using the ammeter and voltmeter. The analysis and use of multisim was spot on with very similar and correct results. However, the actual circuit currents did not match the analysis and multisim values close enough. This discrepancy could have been caused by many different errors including personal or instrumental. ' 25 J "r 7) ,0247('§;0J_L M '3 15 n. VT: (Maggi; .~. Li. 3 9 v fink/imam .l. R4 I5~l3 M) : .0); A 266112ch + VSJH 7v '3 5. ,fl 3 (@K% > I £2th 20011 KWHmw :6: .0071: .019 .02'f7 : (warm/200g); Lrfl 'fu Part VI: Discussion and Analysis A. Circuit S-Voltages 1-6 C t r Error Analysis Theoretical(v) Measured(v) Simirlrggsw) Emory vcsi. easure 10.01 14.93 60% 4-95 1.01% 1.01% Circuit 5-Currents 1-6 Com uter Error Analysis Theoretical(ma) Measured(ma) Simulatgomma) Theory vcsl. Measure / Parts B. and C. are included along with the pre work for this lab. _/ or .3092. on .v Gown em m cmooéw Un— cmoc-§ On. | + m: 222 on ("HWMJ m: 222 on .iww.-j Tami _ > an M» ,\|1l_l k' 1>\\<l + doom _. PM 223. OD fill ESP l. 83 M 1'43, 4 Vflii C FEE: u ND 1 .YI., :J Data Summary Sheets ENGR 361 and ENGR 363 Experiment One Namr Figure 5-d1: Circuit for Experiment One Indicate polarity of each voltage directly on the figure above. Indicate direction of each current directly on the figure above. Record the numerical values below. _-.m- J m m l m A ll m Exp. 1 Pg. 10 Part V. Measurements E D 20052 . c_ Figure 5-d2: Circuit for Experiment One Indicate polarity of each'measured voltage on the figure above. Indicate direction of each measured current on the figure above. Record the numerical values below. Resistor Revised 9/6/2010. Exp. 1 Pg. 11 Grading Sheet for Experiment One summary? Report Format: Discussion of goals and objectives? Organization (5) (5) Expression of ideas? (5) Experimental concept and procedure? (5) __.___.-.. Mechanics (spelling, grammar, etc.) (5) Part I: Ammeter £31511: Voltmeter Part III: Voltmeter Design (10) Measurement of Rm? (10) Circuit analysis (Figure 5) and computer simulation? (15) Part V: Circuit (Figure 5) measurements? (20) P VI: Analysis and comparison to theory? (A): Currents and voltages (8) ____———- (B): Verification of Kirchhoff's Laws using measured values (8) __——- (C): Condition for measuring resistance (4) _...__.—-— Exp. 1 Pg. 9