The Siemens SIRIUS 3RH6140-1BB40 is a size S00 contactor relay with four normally open (NO) auxiliary contacts — the 40 E switching-element identifier means 4 NO, zero NC. The 24 VDC coil draws 4 W closing and 4 W holding, so the control transformer or PLC output must source that continuous load. It is rated for 6 A at 24 V (AC-12) and can switch up to 10 A at 230 V, 3 A at 400 V, or 1 A at 690 V, making it suitable for pilot-duty and signal-level loads in motor control centers and panel builders' auxiliary circuits.
The 45 mm width and 73 mm depth fit standard S00 contactor spacing, leaving room for an auxiliary switch block alongside. Mounting position is flexible: ±180° rotation on a vertical surface, plus ±22.5° tilt forward/backward, which helps when routing wires in a crowded enclosure. Screw-type terminals accept 2 x (0.5 to 2.5 mm²) solid/stranded or 2 x 4 mm² — no special ferrule needed for the auxiliary and control circuit connections.