Allen Bradley Guardmaster 440R Safety Relay Troubleshooting and Configuration Guide

Allen Bradley Guardmaster 440R Safety Relay Troubleshooting and Configuration Guide

Introduction: On site challenges of modular safety relays

In modern factory automation systems, safety relays are the core safety logic components that connect input devices such as emergency stop buttons, safety door switches, light curtains, safety carpets, and output actuators such as contactors and drivers. Guardmaster of Rockwell Automation ®  Safety Relay (GSR) series (including 440) R‑S13R2 CI、440R‑D22R2 DI、440R‑D22S2 DIS、440R‑EM4R2 EM、440R‑EM4R2D EMD  The 440R-S12R2 SI adopts a 22.5mm ultra-thin design, supporting single wire secure (SWS) communication, configurable logic (AND/OR), and pulse test diagnosis. For on-site maintenance engineers, quickly identifying LED flashing patterns, checking input/output wiring, and understanding timing functions are key to restoring safety circuits and reducing downtime.

This article combines the official user manual to provide an executable technical guide from six dimensions: hardware selection, wiring specifications, configuration process, LED diagnosis, common troubleshooting, and safety level requirements.

Model Overview and Selection Basis

The GSR series includes multiple models, and their input/output and main functions are compared as follows:

Model Catalog Number Safety Input Safety Output Auxiliary Output SWS Delay/Function

CI 440R-S13R2 1 channel dual channel 3 N.O. electromechanical 1 N.C. electromechanical only outputs none

SI 440R-S12R2 1 channel dual channel 2 N.O. electromechanical 1 PNP output only none

DI 440R-D22R2 2-channel dual channel 2 N.O. electromechanical 1 PNP input+output logic AND/OR

DIS 440R-D22S2 2-channel dual channel 4 PNP OSSD 1 PNP input+output logic AND/OR, high-capacity load output

EM 440R-EM4R2 only has SWS input 4 N.O. electromechanical 1 PNP input+output (direct) none

EMD 440R-EM4R2D SWS Input+B1/B2 4 N.O. Delay Electromechanical 1 PNP Input+Output Close Delay, Open Delay, Jogging

Selection Tips:

When expanding the number of output contacts, use EM or EMD as the slave station (connected to the host through SWS).

If delayed output (such as pressure relief behind a safety door) or jog function is required, EMD must be selected.

For capacitive loads such as the Safe Torque Off input of PowerFlex drives, it is recommended to use DIS 34/44 terminals (capable of withstanding 9 μ F capacitors).

CI/SI can directly replace the old MSR127/MSR126 models.

Installation and wiring points

3.1 Mechanical Installation

DIN rail: 35mm (EN 50022), directly clamped. Use a screwdriver to pry down the bottom latch during disassembly.

Spacing: Reserve at least 50.8mm ventilation distance above and below.

Shell protection: IP40 (NEMA 1), to be installed in control cabinets with IP54 or higher.

3.2 Terminal Wiring

All terminals are compatible with 0.2... 2.5 mm ² (24... 14 AWG) copper wire, with a torque of 0.4 N · m (4 lb · in). The terminal block is pluggable, and a small screwdriver can be inserted into the top slot to pry and remove it (refer to Figure 4 in the manual). Key terminal functions:

Terminal function

A1 24V DC power supply (+10%/-15%)

A2 24V common terminal

S11, S21 pulse test output (for mechanical contacts)

S12, S22 secure input channel 1/2 (first channel)

S32, S42 secure input channel 1/2 (second channel, only DI/DIS)

634 Reset/Monitor Input

L11 Single Wire Safety (SWS) Output

L12 Single Wire Safety (SWS) Input

Y32/X32 auxiliary output (PNP, conducting when safety output is disconnected)

13/14, 23/24... Safe output (N.O. or OSSD)

B1, B2 only EMD: jog input or can be triggered again to close delay input

3.3 Grounding Requirements

A 24V power supply certified by PELV or SELV must be used.

The 24V common terminal (A2) must be single point grounded to the protective ground (PE), otherwise it may cause false faults due to common mode noise (refer to Figure 61 in the manual).

If SELV is used and cannot be grounded, floating ground can be retained (but NFPA79 does not allow it).

Configuration Process (Five Step Method)

The GSR safety relay sets the logic, reset type, and delay through the front panel rotary switch. Before configuration, the input circuit must be closed (if the emergency stop button is not pressed).

Turn off the power and set the switch to position 0 (DI/DIS logic switch to 0); Set the CI/SI reset switch to 0; Set the Range and Time of EMD to 0, 1, or 10 respectively.

Power on: The PWR/Fault LED flashes red at 1Hz (indicating that the old configuration has been cleared and waiting for a new configuration).

Turn the switch to the desired position (refer to the table below).

Confirm configuration: The corresponding status LED will indicate the current switch position by the number of flashes (for example, if the LOGIC IN LED of EMD flashes 4 times, it indicates Time=4).

Power off and then power on: The new configuration is stored in EEPROM, and the device enters normal operation.

4.1 DI/DIS logic switch (10 levels, only used 1-8)

Position reset type logical expression

1. Manual monitoring (IN1 OR IN2) OR L12

2 Monitoring Manual (IN1 AND IN2) OR L12

3 Monitoring Manual (IN1 or IN2) AND L12

4 Monitoring Manual (IN1 AND IN2) AND L12