Clear (Clr); Relay Ladder; Structured Text - Allen-Bradley Logix5000 Reference Manual

Move/Logical Instructions (MOV, MVM, BTD, MVMT, BTDT, CLR, SWPB, AND, OR, XOR, NOT, BAND, BOR, BXOR, BNOT)

Clear (CLR)

dest := 0;
Description:
Arithmetic Status Flags:
Fault Conditions:
Condition
Prescan
Rung-condition-in is false
Rung-condition-in is true
Postscan
The CLR instruction clears all the bits of the Destination.
Operands:

Relay Ladder

Operand
Destination

Structured Text

Structured text does not have a CLR instruction. Instead, assign 0 to the tag you want to
clear. This assignment statement clears dest.
See Structured Text Programming
assignment statements within structured text.
The CLR instruction clears all the bits of the Destination.
Arithmetic status flags are affected.
None
Execution:
Relay Ladder Action
The rung-condition-out is set to false.
The rung-condition-out is set to false.
The instruction clears the Destination.
The rung-condition-out is set to true.
The rung-condition-out is set to false.
Rockwell Automation Publication 1756-RM003N-EN-P - October 2011
Type Format
SINT Tag
INT
DINT
REAL
for information on the syntax of expressions and
Description
Tag to clear
Chapter 7
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