The Siemens SIRIUS 3RH2140-1HB40 is a coupling relay — a contactor-style device built to switch auxiliary circuits in control panels. The size S00 footprint (45 mm wide, 73 mm deep, 57.5 mm high) keeps it compact for dense panel layouts. The 24 VDC coil draws 2.8 W on both closing and holding — no power penalty for keeping it energized.
Terminals accept solid or stranded wire: 2× (0.5 to 1.5 mm²), 2× (0.75 to 2.5 mm²), or 2× 4 mm².
Switching capacity across voltages
The 4 NO contacts are rated for switching across a wide voltage range. At 24 V the rated current is 10 A; at 230 V it's also 10 A. Higher voltages see derating: 3 A at 110 V, 1.2 A at 220 V, 3 A at 400 V, 2 A at 500 V, 1 A at 690 V, and 0.26 A at 600 V. The DC ratings at 60 V and 440 V are 4.7 A and 0.5 A respectively — useful for mixed AC/DC control circuits.