Allen-Bradley SLC 500 Series User Manual

Publication 1747-RM001G-EN-P - November 2008
2-20 Basic Instructions
Reset (RES)
Use a RES instruction to reset a timer or counter. When the RES instruction is
enabled, it resets the Timer On Delay (TON), Retentive Timer (RTO), Count
Up (CTU), or Count Down (CTD) instruction having the same address as the
RES instruction.
When resetting a counter, if the RES instruction is enabled and the counter
rung is enabled, the CU or CD bit is reset.
If the counter preset value is negative, the RES instruction sets the
accumulated value to zero. This in turn causes the done bit to be set by a count
down or count up instruction.
(RES)
Output Instruction
Fixed SLC
5/01
SLC
5/02
SLC
5/03
SLC
5/04
SLC
5/05
• •••••
Table 2.13 Using an RES Instruction
Using a RES instruction for a: The processor resets the:
Timer
(Do not use a RES instruction with a TOF.)
ACC value to 0
DN bit
TT bit
EN bit
Counter ACC value to 0
OV bit
UN bit
DN bit
CU bit
CD bit
Control POS value to 0
EN bit
EU bit
DN bit
EM bit
ER bit
UL bit
IN and FD go to last state
ATTENTION
Because the RES instruction resets the accumulated
value, and the done, timing, and enabled bits, do not
use the RES instruction to reset a timer address used
in a TOF instruction. Otherwise, unpredictable
machine operation or injury to personnel may occur.

Allen-Bradley SLC 500 Series Specifications

General

Brand	Allen-Bradley
Model	SLC 500 Series
Category	Controller
Language	English