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
SF_CTUD
This FB creates an up-down counter that operates according to an up-counter input and a down-coun-
ter input.
• This FB creates an up-down counter that operates according to an up-counter input signal and a
down-counter input signal.
• The counter has the functions of both an up counter and a down counter.
• The preset value and counter value must have a SAFEINT data type.
Instruction Name FB/FUN Graphic expression
SF_CTUD Up-down Counter FB
Variables
Input Variables
Variable Name Data type Valid range Default Description
CU Up counter input BOOL TRUE or FALSE FALSE Up counter input
CD Down-counter input BOOL TRUE or FALSE FALSE Down-counter input
RESET Reset signal BOOL TRUE or FALSE FALSE TRUE: Reset CV to 0.
LOAD Load signal BOOL TRUE or FALSE FALSE TRUE: Set CV to PV.
PV Preset value SAFEINT 0 to 32767 0 This is the count-up value for an up
counter or the initial value for a
down counter.
Output Variables
Variable Name Data type Valid range Default Description
QU Up-counter output SAFEBOOL TRUE or FALSE FALSE TRUE: CV is greater than or equal
to PV.
FALSE: CV is less than PV.
QD Down-counter out-
put
SAFEBOOL TRUE or FALSE FALSE TRUE: CV is 0 or lower.
FALSE: CV is 1 or higher.
CV Counter value SAFEINT 0 to 32767 0 Counter present value
Function
SF_CTUD
CU
CD
RESET
LOAD
PV
QU
QD
CV

Omron NX-SL series Specifications

General

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