Rockwell Automation 1772-LS_LSP,D17726.8.6 PROG/OPER MANUAL-MINI PLC-2/05 - Manual (Page 247)

Glossary
Appendix B
BĆ11
Limit Switch
An electrical switch actuated by some part and/or motion of a machine
or equipment.
Line
1) A component part of a system used to link various subsystems located
remotely from the processor. 2) The source of power for operation. Example:
120V AC line.
Load
1) The power used by a machine or apparatus. 2) To place data into an internal
register under program control. 3) To place a program from an external storage
device into central memory under operator control.
Local I/O Processor
A processor where I/O distance is physically limited and must be located near
the processor. However, it may still be mounted in a separate enclosure. See
Remote I/O Processor.
Location
A storage position in memory. Uniquely specified in Allen-Bradley processors
by a 5-, 6-, 7-, 8-, or 9-digit address.
Logic
A systematic means of solving complex problems through the repeated use of
the AND, OR, NOT functions (they can be either true or false). Often
represented by ladder diagrams.
Logic Diagram
A diagram which represents the logic elements and their interconnections.
Logic Level
The voltage magnitude associated with signal pulses representing ones and
zeros (1 and 0) in binary computation.
Loop
A sequence of instructions which is executed repeatedly until a terminating
condition is satisfied.
Low = True
A signal type where the lower of two voltages indicates a logic state of on (1).
See High = True.
Lower Nibble
The four least significant bits of a byte.
LSB
See Least Significant Bit.