Active production — no lifecycle surprises
The 3RU2126-4CC1: Part of the Siemens SIRIUS family, this is a thermal overload relay — Size S0 frame, Trip Class 10, rated for motor circuits up to 690 V.
Motor power coverage and trip class
At 400 V the relay covers 11 kW motor loads; at 690 V it covers 18.5 kW. The AC-3e rated voltage max is 690 V, matching the main circuit rating.
Termination and wiring
Main current circuit uses spring-loaded terminals — no screw torque to check, just push in solid or ferruled stranded wire up to 2x 2.5 mm² per clamp. Auxiliary switch is integrated; its contact ratings cover 24 V at 2 A, 120 V at 3 A, and 230 V at 2 A — enough for PLC input or contactor coil feedback.
Operates from -40 to +70 °C, stores and transports at -55 to +80 °C. Temperature compensation is active from -40 to +60 °C, so the trip curve stays accurate across the working range. The relay is RoHS-compliant per the substance prohibition date of 10/01/2009. MTTF with high demand rate is 2,280 years — a reliability figure for safety-related applications.