It snaps onto the DIN rail alongside the main contactor, adding auxiliary contact blocks without increasing the panel's vertical height — the 10 mm width is the only added DIN rail footprint. Rated operational currents vary by voltage: 6 A at 24 V, 2 A at 48 V and 60 V, 1 A at 110 V, 0.9 A at 125 V, 0.3 A at 220 V and 250 V, 6 A at 230 V, and 3 A at 400 V. For AC-15 inductive loads at 690 V, it carries 1 A — this is the rating that governs switching of contactor coils and solenoid valves in a 690 V panel.
The 3RH6921-1DA02 is a mirror contact per IEC 60947-4-1, meaning its normally closed (NC) contacts mechanically mirror the main contactor's state — essential for safety circuits that must detect a welded contactor. The IP20 front protection means it's safe from finger contact in an enclosed panel but not washdown-rated. Wire termination accepts 2x (0.5 to 1.5 mm²) or 2x (0.75 to 2.5 mm²) solid or finely stranded with ferrule — or 2x (20 to 16) and 2x (18 to 14) AWG.