Allen-Bradley Logix5000

Rockwell Automation Publication 1756-RM003N-EN-P - October 2011 153
Timer and Counter Instructions (TON, TOF, RTO, TONR, TOFR, RTOR, CTU, CTD, CTUD, RES) Chapter 3
Reset (RES)
The RES instruction resets a TIMER, COUNTER, or CONTROL structure.
Operands:
Relay Ladder
Description: When enabled the RES instruction clears these elements.
Arithmetic Status Flags: Not affected
Fault Conditions: None
Execution:
Operand Type Format Description
Structure TIMER
CONTROL
COUNTER
Tag Structure to reset
When using a RES
instruction for a
The instruction clears
TIMER .ACC value
Control status bits
COUNTER .ACC value
Control status bits
CONTROL .POS value
Control status bits
ATTENTION: Because the RES instruction clears the .ACC value,
.DN bit, and .TT bit, do not use the RES instruction to reset a TOF
timer.
Condition Relay Ladder Action
Prescan The rung-condition-out is set to false.
Rung-condition-in is false The rung-condition-out is set to false.
Rung-condition-in is true The RES instruction resets the specified structure.
The rung-condition-out is set to true.
Postscan The rung-condition-out is set to false.