S00 frame, 4 NO contacts, 125 V DC coil
The Siemens 3RH2344-1BG40 is a SIRIUS auxiliary contactor in the S00 frame size, carrying 4 normally-open instantaneous contacts and a 125 V DC magnet coil. This is the part you reach for when the main contactor's auxiliary block is full and you need to mirror a status back to the PLC or latch a holding circuit without adding another power contactor. The coil draws 4 W both on pickup and hold — no economizer circuit needed, the DC coil holds at full power continuously. That 4 W steady-state load matters if you're stacking several of these in a panel with limited heat dissipation.
Rated operational current across the voltage range
The 690 V rating is 1 A. These are the AC-15 / DC-13 utilization category figures for the auxiliary contacts — the switching capacity drops as voltage climbs because the arc energy grows faster than the contact gap can quench. For DC switching, the arcing time runs 10 to 15 ms with a 7 to 13 ms dropout delay — the DC arc doesn't self-extinguish at zero-crossing, so the contact material and arc-chute geometry are tuned for that window. If you're switching inductive DC loads (brake coils, solenoid valves), verify the load's L/R time constant against the contactor's DC breaking capability.
RoHS compliant with a substance prohibition date of 07/01/2006 — meets the original EU RoHS directive. The mechanical endurance is 10 million switching cycles typical, which for a purely auxiliary switching load (PLC inputs, contactor coils, signal lamps) translates to a long service life in normal cycling duty.