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Glossary – Rockwell Automation 1747-L5xx SLC 500 Modular Hardware Style User Manual User Manual

Page 271

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271

Publication 1747-UM011G-EN-P - June 2008

Glossary

We use the following terms throughout this manual. Refer to the
Allen-Bradley Industrial Automation Glossary, publication AG-7.1, for
a complete guide to Allen-Bradley technical terms.

address

A character string that uniquely identifies a memory location. For
example, I:1/0 is the memory address for data in Input file word 1, bit
0.

AIC+ Advanced Interface Converter

A device that provides RS-232 isolation to an RS-485 half-duplex
communication link. (catalog number 1761-NET-AIC.)

application

1) A machine or process monitored and controlled by a controller.
2) The use of computer- or processor-based routines for specific pur-
poses.

auto answer

Type of modem that has self-contained timeouts and tests. It can
answer and terminate a call automatically.

backplane current draw

The amount of current the module requires from the backplane. The
sum of the backplane current draw for all modules in a chassis is used
to select the appropriate chassis power supply.

baud rate

The speed of communication between devices on a network. All
devices must communicate at the same communication rate. For
example, the DH-485 network devices default to 19.2 Kbaud.

bit

The smallest unit of memory used in discrete or binary logic, where
the value 1 represents ON and 0 represents OFF.

block diagrams

A method used to illustrate logic components or a sequence of events.