Allen-Bradley 440R-M23143 Safety Relay Module

The Allen-Bradley 440R-M23143 Safety Relay Module is the MSR138DP single-function safety relay in the Guardmaster 440R family, designed to monitor safety devices and provide safe-stop control for industrial machinery. It operates from a 24-volt supply (24 VAC or 24 VDC) and offers two safety contacts for switching safety-rated outputs, with support for a delayed-output function that enables controlled-stop sequences without sacrificing response time to safety events. Common applications include emergency stops, safety interlocks, and protective devices on conveyors, presses, robots, and other automated equipment where a failsafe shutdown is required; it integrates safety signals from devices such as E-stops and light curtains into a single, verifiable safety circuit. As part of the MSR138DP family, the 440R-M23143 is a compact, trusted safety relay module that combines simple wiring with robust safety monitoring to help plants meet basic safety requirements without adding complexity to the control system.