The Siemens SIRIUS 3RT2946-1CF00 is a surge suppressor built as an RC element, sized for S3 contactors in the 3RT2.4 family. It clips directly onto the contactor coil terminals to suppress voltage spikes when the coil de-energizes — a standard fit for any panel using 3RT2.4 contactors on AC control supplies. At 25 mm wide, 22.6 mm deep, and 55 mm tall, it adds minimal DIN-rail footprint alongside the contactor — no extra panel space required beyond the contactor's own width.
Why the RC element matters for your contactor
An RC surge suppressor does two things: it snubs the inductive kick from the contactor coil when it drops out, and it reduces electromagnetic interference radiated back into the control wiring. On a 3RT2.4 contactor switching motor loads, that means longer contact life and less noise on the PLC inputs sharing the same panel. Because it's designed specifically for the S3 frame size of the 3RT2.4 series, the mechanical fit is direct — no adapter brackets or flying leads to route. The RC element bridges the coil terminals, so the wiring order is coil first, suppressor second.