Omron NX-SL series User Manual

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1 Introduction to Instructions for Safety Control Units and Interpreting Instruction Descriptions
NX-series Safety Control Unit Instructions Reference Manual (Z931)
1-2 Interpreting Instruction
Descriptions
1
1-2-1 Items
1-2 Interpreting Instruction Descriptions
The notation that is used to describe instructions is explained in this section.
The following items are provided. The order of the items is not the same for all instructions. If there are
items that are specific to one type of instruction, they are explained in the section for each instruction
type.
1-2-1 Items
Item Description
Instruction The instruction word is given.
Name The name of the instruction is given.
FB/FUN Whether the instruction is a function block (FB) instruction or a function (FUN) instruction
is given.
Graphic expression The figure that represents the instruction in a function block diagram is given.
Instance specification: An instance of an instruction is indicated by “XX_instance” above a
FB instruction. You must assign an instance name to any instance of an instruction that
you specify.
Variables • Variable
The input variable or output variable is given.
•Name
The name of the variable is given.
Example: Up-counter
• I/O
Whether the variable is an input variable or output variable is given.
• Description
The meaning of the variable and any restrictions are given.
• Valid range
The range that the variable can take is given. “Depends on data type” indicates that the
valid range of the variable depends on the data type that you use. The valid ranges of
the data types are given later in this section.
•Default
The specified default value is automatically used for the variable if you do not assign a
parameter to the instruction before it is executed. “---” indicates the following:
Input variables: The default value of the data type of the input variable is assigned. The
default values of the data types are given later in this section.
Output variables: Default values are not set.
• Data type
The data type of the variable is given. Broadly speaking, there are two classifications of
data types: safety signals and non-safety signals. These two classifications of data
types are described later.
Instance specification
Input variable
name
Output variable
name
ADD
Instruction word
SF_CTU
CU
SF_CTU_instance
RESET
PV
Q
CV
 Example for a FUN
Instruction
 Example for a FB
Instruction

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