What it is and where it fits
The Siemens 3RH1921-2DA11 is a SIRIUS auxiliary switch designed for lateral snap-on mounting to S0-frame contactors and contactor relays. It adds one instantaneous normally-open contact to the switching block, letting you pick up status feedback or interlock signals without extra wiring layers. Rated for 10 A at 24 V (AC-12) and 6 A at 24 V for general-purpose switching, with derated curves up to 400 V at 3 A. The spring-loaded terminals accept 2x (0.5 to 2.5 mm²) solid or stranded, or 2x (20 to 14 AWG) — no screwdriver needed for the control-circuit connections.
Sourcing and lifecycle
The 3RH1921-2DA11 is listed as current production. It's sourced and quoted to order through independent distribution — availability and current pricing are confirmed at quote time against an RFQ.