Allen-Bradley 440R-N23135 MSR127RP Safety Relay

The Allen-Bradley Guardmaster 440R-N23135 MSR127RP Safety Relay is a 24V AC/DC powered unit that accepts two normally closed safety input channels and provides three normally open safety outputs, plus one normally closed auxiliary contact for monitoring. It features a monitored manual reset to ensure faults are cleared before re-energizing, and uses removable terminals (screw-type in the standard version; spring-clamp variants are also available) for straightforward field wiring. The MSR127RP base width is 22.5 mm, making it compact for panel installations, and it supports an LC input option for light curtains in addition to the two NC inputs. The three NO safety outputs, in conjunction with the OSSD signaling, enable safe interlock of dual-channel safeguarding circuits such as emergency stops and safety light curtains.