Allen-Bradley D Series - Terminology Used in this Manual

Preface
Using This Manual
P-2
The following list defines common terms used in this manual.
Complementary I/O: An I/O technique that allows a PC to interface with
an input and output module using the same location address in different I/O
chassis.
Complementary Module: A module that performs an opposite function;
an input module complements an output module and vice versa.
Standard–Density I/O Module: A module that provides up to 8 input
terminals or 8 output terminals.
High–Density I/O Module: A module that provides 16 input or 16 output
terminals.
Quad–Density I/O Module: A module that provides 32 input or 32 output
terminals.
I/O Group: An addressing unit that can contain up to 16 input terminals
and 16 output terminals.
PC: An Allen–Bradley programmable controller, such as the PLC–5.
Processor: A term used to mean an Allen–Bradley programmable
controller.
Half–Slot Addressing: A method of addressing where the processor can
address its I/O in 1/2–slot I/O groups.
One–Slot Addressing: A method of addressing where the processor can
address its I/O in 1–slot I/O groups.
Two–Slot Addressing: An method of addressing where the processor can
address its I/O in 2–slot I/O groups.
Terminology Used in This
Manual
Allen-Bradley PLCs