The 3RH2911-1HA20 is a SIRIUS auxiliary switch block that snaps onto the front of Siemens contactor relays and power contactors in sizes S00, S0, S2, and S3. It carries two normally-open instantaneous contacts — no delayed or lagging contacts here, just clean make/break on coil pickup. The 6 A rating at 24 V is the AC-15 pilot-duty current for solenoid loads — think PLC outputs, relay coils, or indicator lamps. That derating curve matters when you're switching a bank of contactor coils at a higher control voltage. For dry-circuit signal switching, this block is built to avoid that failure mode.
Snap-on fit and panel wiring
Mounting is tool-free: the block snaps directly onto the front of the contactor or contactor relay. The 36 mm width and 43.7 mm depth keep it within the contactor's own envelope — no extra DIN rail space needed beyond the base device. For AWG, that's 2x (20…16) or 2x (18…14). The screw clamps are captive, so no dropped hardware inside the panel. Front IP20 means finger-safe when mounted on the contactor — no shock hazard during troubleshooting with the panel door open.
Mirror contact and safety circuit use
The 3RH2911-1HA20 is listed as a mirror contact per IEC 60947-4-1 when used with the 3RT2 contactor series. That means the NC mirror contact mechanically reflects the main contact position — critical for safety circuits where you need positive confirmation that the main power contacts have opened before allowing access to the guarded zone. Surge voltage resistance is rated at 6 kV, which covers the impulse withstand for most industrial control panels per IEC 60947-1 overvoltage category III.
Current pricing and lead time confirmed at RFQ — no stock-holding claim here, but it's a standard production part with no supply constraints flagged.