The Siemens 3RA1811-8YA04-1AC0-ZX95 is a SIGUARD safety combination unit rated for DC 230 V control voltage, with screw-type terminals. It is part of the 3RA18 series designed for compact safety switching in industrial control panels — combining a contactor and a safety relay in one housing to reduce wiring and panel space.
The DC 230 V rating governs the control coil voltage — a safety combination that picks up and seals on a 230 VDC supply. If your panel runs a 230 VDC control bus (common in some industrial DC grids or battery-backed systems), this unit drops in without an additional transformer or DC-DC converter. The screw terminals match standard ring or fork lug terminations; no special tooling needed.
Deployment context
It integrates a contactor and a safety relay in one package, so it handles both the safety logic (e-stop, guard door monitoring) and the load switching in a single device — reducing the component count in a safety circuit and simplifying wiring to the motor or actuator.