The Siemens SIRIUS auxiliary switch block 3RH1911-1GA13-ZW98 is a 4-pole block with 1 normally open and 3 normally closed contacts arranged per EN 50011, terminated with screw-type terminals. It snaps onto a contactor relay or power contactor in the SIRIUS family, adding auxiliary signaling or interlocking to the base device. Rated for a maximum of 10 A, the contact ratings vary by voltage: 6 A at 24 V, 6 A at 125 V, 6 A at 230 V, 6 A at 250 V, 3 A at 400 V, and 0.3 A at 220 V. Under AC-15 duty at 690 V it carries 1 A. Front-side protection class is IP20.
This order code is a phased-out product. The manufacturer lists the successor as the SIRIUS 3RH2 series.
Snap-on mounting onto a contactor relay or power contactor means no DIN-rail space is consumed — the block adds directly to the front of the base device. The 36.5 mm width, 37.5 mm height, and 41.5 mm depth keep the assembly compact. Wire termination accepts 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 for auxiliary contacts.