The Siemens 3RH1122-2BD40 is a SIRIUS auxiliary contactor in size S00, rated for a 42 V DC coil. The 10 A AC-12 rating covers resistive and lightly inductive loads typical for control-circuit switching — think PLC outputs, pilot lights, or small contactor coils. The 6 kV rated surge voltage resistance means it's designed for industrial environments with moderate transient energy, not just clean office power.
Wiring and contact configuration
The contactor carries 2 instantaneous contacts and no delayed or make-before-break contacts. The auxiliary switch extension is available as an add-on, so you can field-upgrade contact count without swapping the base unit.
Shock resistance is 10g / 5 ms and 5g / 10 ms — sufficient for normal industrial vibration but not for high-shock applications like stamping presses. RoHS compliance is indicated by the substance prohibitance date of 07/01/2006.