Omron NX-SL series User Manual

3 Safety Standard Function Blocks
3 - 12
NX-series Safety Control Unit Instructions Reference Manual (Z931)
SF_RS
This FB retains the value of a SAFEBOOL variable.
It gives priority to the Reset input if both the Set input and Reset input are TRUE.
• This instruction forms a self-holding output that gives priority to resetting. The following table shows
the relationship between the inputs and outputs.
The following figure shows a programming example and timing chart.
Instruction Name FB/FUN Graphic expression
SF_RS Reset-Priority Keep FB
Variables
Input Variables
Variable Name Data type Valid range Default Description
SET Set SAFEBOOL TRUE or FALSE FALSE Set input
RESET1 Reset BOOL TRUE or FALSE FALSE Reset input (Given priority.)
Output Variables
Variable Name Data type Valid range Default Description
Q1 Keep SAFEBOOL TRUE or FALSE FALSE Keep output
Function
Value of SET Value of RESET1 Value of Q1
TRUE TRUE FALSE
TRUE FALSE TRUE
FALSE TRUE FALSE
FALSE FALSE Not changed.
SF_RS
SET
RESET1
Q1
Set=A
Reset1=B
Q1=abc
TRUE
FALSE
TRUE
FALSE
TRUE
FALSE

Omron NX-SL series Specifications

General

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

Summary

Introduction to Instructions for Safety Control Units and Interpreting Instruction Descriptions

Types of Instructions

Describes the three types of instructions used with Safety Control Units.

Interpreting Instruction Descriptions

Explains the notation used to describe instructions.

Standard Functions

Execution Control Instructions

Details instructions for controlling program execution flow.

Data Type Conversion Instructions

Explains instructions for converting data types between different formats.

Boolean Operation Instructions

Describes instructions for performing logical Boolean operations.

Math Instructions

Details instructions for arithmetic operations on integers and durations.

Comparison Instructions

Instructions for comparing values of variables.

Selection Instructions

Instructions for selecting values based on conditions.

Safety Standard Function Blocks

Safety Standard Function Block Instructions

Lists and describes safety standard function block instructions.

SF_CTD

Decrements the counter value when the counter input signal is received.

SF_CTU

Increments the counter value when the counter input signal is received.

SF_CTUD

Creates an up-down counter operating on up and down counter inputs.

SF_F_TRIG

Outputs TRUE for one task period when the input signal changes to FALSE.

SF_R_TRIG

Outputs TRUE for one task period when the input signal changes to TRUE.

SF_RS

Retains the value of a SAFEBOOL variable, giving priority to Reset.

SF_SR

Retains the value of a SAFEBOOL variable, giving priority to Set.

SF_TOF

Outputs FALSE when the set time elapses after the timer starts.

SF_TON

Outputs TRUE when the set time elapses after the timer starts.

SF_TP

Outputs TRUE during the set time after the timer starts.

Safety Function Blocks

General Rules for Safety Function Blocks

Provides general rules for safety function blocks, including rules specific to FBs.

Safety Function Block Instructions

Lists and describes various safety function blocks.

SF_Antivalent

Monitors discrepancy time for two antivalent SAFEBOOL inputs.

SF_EDM

Controls a safety output and monitors actuator control.

SF_EmergencyStop

Monitors the input from an emergency stop button.

SF_EnableSwitch

Supports stopping a safety function using an enable switch.

SF_Equivalent

Monitors discrepancy time for two equivalent SAFEBOOL inputs.

SF_ESPE

Monitors electro-sensitive protective equipment (ESPE).

SF_GuardLocking

Controls entry to hazardous areas with a four-state interlock guard.

SF_GuardMonitoring

Monitors safety guards and opens/closes them.

SF_ModeSelector

Selects system operation mode (automatic, manual, etc.).

SF_MutingPar

Performs parallel muting with four muting sensors.

SF_MutingPar_2Sensor

Performs parallel muting with two muting sensors.

SF_MutingSeq

Performs sequential muting with four muting sensors.

SF_OutControl

Controls a safety output with control and safety signals.

SF_SafetyRequest

Makes requests for safe state and monitors actuator safety state.

SF_TestableSafetySensor

Tests functionality with external test function of ESPE sensors.

SF_TwoHandControlTypeII

Provides type II, two-hand control function per ISO 13851.

SF_TwoHandControlTypeIII

Provides type III, two-hand control function per ISO 13851.

Index