Siemens 3RH1131-1BB40-ZW98 SIRIUS Auxiliary Contactor — 24 V DC, S00 Frame
The 24 V DC coil pulls in at 0.8 of rated voltage and holds at 3.2 W — a steady-state draw that stays within the typical 24 VDC power supply budget for a PLC output card or control transformer. Rated operational currents scale with voltage: 10 A at 24 V, 6 A at 230 V, 3 A at 400 V, 1 A at 690 V. The 690 V, 1 A rating confirms it can switch a 690 VAC control circuit if the panel uses that voltage class.
At 45 mm wide, 57.5 mm tall, and 72 mm deep, the S00 frame fits standard DIN-rail spacing. Terminals accept solid conductors: 2x 0.5–1.5 mm², 2x 0.75–2.5 mm², or 2x 4 mm². AWG equivalents are 2x (20–16), 2x (18–14), and 1x 12. That covers the common control wire sizes for panel wiring — 1.5 mm² for most signal runs, 2.5 mm² for longer coil feeds where voltage drop is a concern. The IP20 front protection means tools and fingers stay out of the live terminals when the panel door is open, but the contactor itself is not sealed against washdown.
For a BOM freeze or second-source gate, the closest functional peer in the SIRIUS line is the 3RH2122-1BA40 — same S00 frame, same 24 V DC coil, but with a different contact arrangement (2 NO + 2 NC versus the 3 NO + 1 NC on this part). The 3RH2122-1BA40 will drop into the same DIN-rail footprint and wiring pattern, but the contact count difference means a controls drawing review if the spare NO or NC is used for a safety circuit.
Shock resistance is 10g for 5 ms and 5g for 10 ms — adequate for panel-mounted gear in industrial machinery but not rated for direct mounting on a vibrating pump skid. Coil closing and holding power are both 3.2 W DC.