Siemens 3RH1921-1EA20 Auxiliary Contact Block

Siemens 3RH1921-1EA20 Auxiliary Contact Block is a two‑pole, two normally open auxiliary switch that mounts to the side of Siemens Sirius 3RT1 contactors as the first lateral auxiliary. It provides two NO contacts wired through screw terminals (EN 50005) for control circuits in motor starters and automation cabinets. This snap‑on accessory is designed for side mounting on compatible 3RT1 sizes and features a compact 10 mm footprint for neat, space‑efficient installation. The block is rated for up to 6 A at 250 V AC (AC‑15) with an insulation voltage of 500 V and front IP20 protection, making it suitable for standard signaling in industrial wiring. Electrical endurance is specified up to 200,000 cycles at AC‑15 and 230 V, reflecting reliable operation in frequent signaling roles. The 3RH1921-1EA20 auxiliary contact block is commonly used to provide feedback and signaling for the main contactor in control circuits, offering a robust, compact solution that complements compatible Siemens contactors in the 3RT1 family.