Allen-Bradley Logix5000 Reference Manual

Rockwell Automation Publication 1756-RM003N-EN-P - October 2011 249
Compare Instructions (CMP, EQU, GEQ, GRT, LEQ, LES, LIM, MEQ, NEQ) Chapter 5
Execution:
Relay Ladder
Function Block
Condition Action
Prescan The rung-condition-out is set to false.
Rung-condition-in is false The rung-condition-out is set to false.
Postscan The rung-condition-out is set to false.
Rung-condition-in is true
End
Evaluate Limit
Comparison is true.
Comparison is false.
Rung-condition-out is set
to true.
Rung-condition-out is set
to false.
Condition Action
Prescan No action taken.
Instruction first scan No action taken.
Instruction first run No action taken.
EnableIn is cleared EnableOut is cleared, the instruction does nothing, and the outputs are not updated.
EnableIn is set The instruction executes.
EnableOut is set.
Postscan No action taken.

Allen-Bradley Logix5000 Specifications

General

Brand	Allen-Bradley
Model	Logix5000
Category	Controller
Language	English