Integrator note — what this RC suppressor does on the S3 contactor
The Siemens 3RT2946-1CC00 is a SIRIUS RC-element surge suppressor sized for the S3 contactor frame (3RT2.4 series). It clips across the coil terminals to damp voltage transients each time the contactor de-energises — the RC network absorbs the inductive kick that would otherwise radiate EMI or stress the coil insulation. The AC/DC input spans 48–127 V AC at 50/60 Hz and 70–150 V DC, so it covers both common control voltages in a single part. At 23 mm deep, 25 mm wide, 55 mm tall, it mounts directly on the contactor's coil terminals; no extra DIN rail space needed. Because the RC element is a passive network (no polarity-sensitive diode), it works equally on AC and DC coils — a practical advantage when the panel uses mixed control supplies. The 23 mm depth keeps it clear of adjacent wiring ducts or busbars in a tightly packed enclosure.