Omron NX-SL series User Manual

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3 Safety Standard Function Blocks
NX-series Safety Control Unit Instructions Reference Manual (Z931)
3
SF_CTUD
The following figure shows a programming example and timing chart for a PV of INT#3.
Use the SF_CTD instruction or SF_CTU instruction to create a counter that only decrements or only
increments.
Additional Information
CU=A
CD=B
Reset=abc
Load=def
CV=mno
PV=INT#3
QU=ghi
QD=jkl
When CV reaches PV,
QU changes to TRUE.
When RESET changes to TRUE, CV changes to 0.
QU changes to FALSE and QD changes to TRUE.
When Reset changes to FALSE, the counter inputs are enabled.
When CU changes to TRUE, CV is incremented.
This causes QD to change to FALSE.
When CD changes to TRUE, CV is decremented.
When CV reaches 0, QD changes to TRUE.
When Load changes to TRUE, CV changes to PV .
This causes QU to change to TRUE and QD
to change to FALSE.
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Omron NX-SL series Specifications

General

Brand	Omron
Model	NX-SL series
Category	Control Unit
Language	English