The Siemens SIRIUS 3RH1911-1GA04-ZW98 is a 4-pole auxiliary switch block with 4 NC contacts (44 E per EN 50011), terminated via screw-type terminals. It snap-mounts onto a DIN rail alongside SIRIUS contactor relays and power contactors, sharing the same 36.5 mm width footprint.
This auxiliary block carries a maximum thermal current of 10 A, but the switching capacity varies sharply with voltage and duty. At 24 V DC it switches 6 A; at 60 V DC it drops to 2 A; at 110 V DC it handles 1 A; at 220 V DC only 0.3 A. The AC-15 rating at 690 V is 1 A — that's the inductive load curve for contactor coils and solenoid valves. For resistive loads (AC-12), the 24 V DC rating climbs to 10 A. The takeaway: if you're switching a 24 V DC PLC output to a small relay coil, the 6 A figure gives comfortable headroom; if you're switching a 220 V DC brake solenoid, the 0.3 A limit means you need a larger contact block or an interposing relay.
Lifecycle status — phased out, successor identified
The 3RH1911-1GA04-ZW98 is a phased-out product. The manufacturer lists the SIRIUS 3RH2 series as the official successor. For BOM continuity, the 3RH2 blocks share the same 36.5 mm width and snap-on mounting, but verify the contact configuration and terminal layout against your panel wiring diagram before substituting.
Integration notes
Depth is 41.5 mm, height 37.5 mm. Screw terminals accept 2x (0.5 to 1.5 mm²) or 2x (0.75 to 2.5 mm²) with core-end processing, or 2x (20 to 16) and 2x (18 to 14) AWG. Surge voltage resistance is 6 kV, insulation voltage 690 V AC at pollution degree 3.