Allen‑Bradley 440R-EM4R2 Guardmaster EM Expansion Module is an expansion relay for Guardmaster 440R safety relays, enabling additional safety inputs and outputs in a single compact enclosure. This 24 VDC expansion module provides one single-wire safe (SWS) input and four normally open (NO) outputs, allowing expanded monitoring and control of safety devices such as interlocks and safety relays in automated systems. Designed for use with the Guardmaster 440R safety family, the EM4R2 supports scalable safety architectures for machine guarding and emergency-stop circuits in industrial environments.
