The Siemens 3RH1140-1AN60 is a SIRIUS auxiliary contactor, Size S00, with 4 normally open (NO) instantaneous contacts. It's rated for 10 A at AC-12 duty, which covers the control-circuit switching you'd expect from an auxiliary block — relay coils, contactor coils, PLC digital inputs, that class of load. The 45 mm width and screw-and-snap-on mounting mean it clips directly onto a DIN rail in the same footprint as the S00 contactor it pairs with.
What the ratings mean for fit
The 10 A AC-12 rating is the key number for control-circuit duty — it's the maximum resistive current the contacts can make and break. For inductive loads like contactor coils, derate to the AC-15 values: 6 A at 230 V, 3 A at 400 V, 1 A at 690 V. The 4 NO configuration gives you four independent auxiliary circuits, which is enough to signal 'contactor on' back to a PLC, interlock a second starter, and still have a spare for a local pilot light. Wire termination accepts 2x 0.5-1.5 mm², 2x 0.75-2.5 mm², or 2x 4 mm² solid — that covers standard control wiring up to 12 AWG. The IP20 front protection is typical for inside a panel; no washdown rating here, so keep it behind the enclosure door. Operating temperature spans -25 to +60 °C, storage from -55 to +80 °C. Shock resistance is 10g / 5 ms and 5g / 10 ms — fine for normal industrial vibration on a machine base or conveyor section.
Mounting and panel integration
Screw and snap-on mounting onto a 35 mm DIN rail. The Size S00 footprint is 45 mm wide, 57.5 mm high, 72 mm deep. Mounting position allows +/-180° rotation on a vertical surface and +/-22.5° tilt forward/backward — useful when you're cramming components into a tight gland plate layout. Zero side clearance required for adjacent devices, so you can butt it against the next S00 contactor or overload relay.