The Siemens SIRIUS 3RT1975-5QP31 is a changeover operating mechanism — essentially a magnet coil assembly — designed for the 3RT107 and 3RT147 series power contactors. It operates on AC/DC control supply voltage, rated at 200 V DC and 277 V AC (both 50 and 60 Hz), and includes an electronic module with AS-Interface communication and an RLT signal output.
What the ratings mean for fit
The 200-277 V AC/DC control voltage range covers common global control voltages — 208 V, 220 V, 240 V, and 277 V panels — without needing a separate transformer tap. The AC/DC type means it works on both rectified DC buses and standard AC control circuits, simplifying panel wiring. This is a changeover operating mechanism, not a standard contactor coil. It mounts onto the 3RT107 (size S12) and 3RT147 contactor frames, providing mechanical interlocking for reversing or two-speed applications. The electronic module handles the timing and includes AS-Interface for status feedback and an RLT (Remote Local Trip) signal.
Sourcing and lifecycle
For panels originally specified around the 3RT1076-6AU36 power contactor, this coil is the correct mating changeover mechanism. The 3RT1076-6AU36 is a size S12 contactor with screw terminals; the 3RT1975-5QP31 bolts onto it without rewiring the main power circuit, though the control wiring must match the 200-277 V AC/DC coil rating.
Deployment context
Designed for panel-mount integration with SIRIUS contactors in motor control centers, conveyor systems, and pump stations. The AS-Interface link allows direct connection to an AS-i master for status monitoring without additional I/O wiring.
