Intro to Allen-Bradley’s bar coder reader page 1 of 5 MFET 374 Manufacturing Integration I Introduction to Allen-Bradley’s Bar Code Reader The following Allen-Bradley bar code equipment is installed at each dropline of the MFET conveyor system: 1 – Decoder, part number: 2755-DD1A-B2-R1 2 - Scanners, part number: 2755-LD4-B1 Up to two scanners can be connected to each decoder. The bar code scanner contains a visible laser diode which is used to scan the bar code label that is attached to a package, pallet, or part. The decoder supplies power to the scanner and the scanner outputs a signal to the decoder based on the scanned bar code label. The decoder must decode (interpret) the signals sent from the scanner. Basically the decoder translates the signals sent from the scanner into data characters using a specific set of rules for each symbology. The symbology is the “language” of the bar code symbol. A symbology is a set of rules which define how the black lines and white lines are organized in order to define characters. After the decoder decodes the data sent from the scanner, it can send the bar code data to a host computer (or PLC) connected to the decoders host port, a terminal connected to the decoders Auxiliary(AUX) port, or the LCD display that is built into the decoder. Decoder Features The 2755-DD1A-B2-R1 decoder has a NEMA Type 1 enclosure. Figure 1 illustrates the decoder used in the MFET laboratory. Some of the features of the bar code decoder are explained below. For more details about the decoder refer to the following Allen-Bradley manual: 2755-DS/DD user manual (Publication 2755-833-November 1996) For more details about the bar code scanners refer to the following Allen-Bradley manual: High Performance Visual Laser Diode Scanner user manual (Publication 2755-832-May 1997)
has intentionally blurred sections.
Sign up to view the full version.