The Siemens 3RH1140-1BF40-0AA6 is a SIRIUS auxiliary contactor in frame size S00, carrying four normally-open instantaneous contacts and a 110 V DC coil. It is designed to switch control signals and auxiliary loads in motor control centers and panel builds — not to switch main motor current, but to extend the I/O of a contactor or relay base.
The contacts are rated for switching at several voltage levels: 10 A at 24 V, 6 A at 230 V, 3 A at 400 V, 2 A at 500 V, and 1 A at 690 V. These are the thermal current ratings for the contact set — they define the maximum continuous current the contacts can carry at each voltage. For a 24 V DC control circuit, the 10 A rating gives ample headroom for pilot lights, solenoid valves, and PLC input modules. At 690 V, the 1 A rating still handles most auxiliary transformer and indicator loads.
The footprint is 45 mm wide, 57.5 mm tall, and 72 mm deep — a compact S00 envelope that fits standard 45 mm DIN-rail spacing. Wire sizing for the auxiliary contacts accepts 2x (0.5 to 1.5 mm²), 2x (0.75 to 2.5 mm²), or 2x 4 mm² solid, plus the AWG equivalents. The spring-cage or screw terminals (fastening method is screw and snap-on) handle the range cleanly — strip length and ferrule choice follow standard panel practice.
Shock resistance is 10g for 5 ms and 5g for 10 ms, and pollution degree is rated 3 (conductive pollution or dry non-conductive pollution that becomes conductive due to condensation). The substance prohibition date of 07/01/2006 indicates RoHS compliance per the EU directive effective from that date.