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Rockwell Automation 1772-L8_LW_LWP_LX_LXP,D17726.5.8 User Manual User Manual

Page 432

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Glossary

Appendix D

D-13

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.

Load Resistor
A resistor connected in parallel with a high impedance load so the output
circuit driving the load can provide at least the minimum current required
for proper operation.

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 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.

LSD
See Least Significant Digit.