The Siemens 3RH2140-2BB40 is a SIRIUS auxiliary contactor in size S00, carrying 4 normally open instantaneous contacts and a 24 VDC coil. The 73 mm depth and 45 mm width keep it compact for dense control cabinets.
Contact ratings by voltage
The 4 NO contacts are rated for switching at multiple voltage levels: 10 A at 24 V AC, 10 A at 230 V AC, 3 A at 400 V AC, and 1 A at 690 V AC. For DC switching, ratings drop to 4.7 A at 60 V, 3 A at 110 V, 1.2 A at 220 V, and 0.5 A at 440 V. These voltage-dependent ratings let you match the contactor to the specific control or auxiliary circuit voltage without oversizing.
Snap-on or screw-fixed to 35 mm DIN rail. These clearances matter for heat dissipation and arc flash containment — don't crowd it against other components.
Coil and switching characteristics
The DC coil draws 4 W closing power and 4 W holding power. Arcing time runs 10 to 15 ms, with a DC switching rate of 7 to 13 ms. The contactor is rated for 10,000 AC operations per hour and a typical mechanical life of 30,000,000 operations.