The Siemens SIRIUS 3RT2926-1ER00-ZX90 is a surge suppressor built with a diode assembly, designed specifically for DC 24 V control circuits on S0-size contactors. It clips directly onto the contactor coil terminals — no extra wiring path needed — and suppresses the inductive kickback that would otherwise weld auxiliary contacts or damage the PLC output driving the coil.
Fastens via clip-on onto the contactor — no tools, no DIN-rail slot consumed. Depth is 12 mm, width 30 mm, height 19 mm; it sits flush on the contactor face and stays within the S0 envelope.
Lifecycle status is current — this is an active catalog item, not a phase-out or NRND part.