Rockwell Automation 1772-LV Mini-PLC - 2/15 Programmable Controller (Series B) Programming and Operations - Manual (Page 199)

Glossary
Appendix B
BĆ6
Diagnostic Program
A user-inserted test program to help isolate hardware malfunctions in the
programmable controller and application equipment.
Direct Current (DC)
An electric current which flows in only one direction.
Downtime
The time when a system is not available for production due to required
maintenance.
Edit
To deliberately modify the user program in the PC memory.
Electrical-optical Isolator
A device which couples input to output using a light source and detector in the
same package. it is used to provide electrical isolation between input circuitry,
output circuitry, and processor circuitry. Same as opto-electrical.
Enable
To cause a particular function to occur by means of preconditions with PC
program logic.
Enclosure
A surrounding case designed to provide a degree of protection for equipment
against a specified environment and to protect personnel against accidental
contact with the enclosed equipment.
Energize
This instruction sets a data table bit to “1” (on) if the preconditions in its rung
are true. The bit is reset to “0” (off) if the preconditions are false.
Examine Off
This instruction is a true precondition if its addressed data table bit is off (“0”).
It is false if the bit is on (“1”).
Examine On
This instruction is a true precondition if its addressed data table bit is ON (“1”).
It is false if the bit is off (“0”).
Execution
The performance of a specific operation such as would be accomplished
through processing one instruction, a series of instructions, or a complete
program.
Execution Time
The total time required for the execution of one specific operation.
Extended Data Comparison
A user-programmed on-line application diagnostic routine. At various steps in