It carries one normally-open instantaneous contact — no leading or lagging function, just a straight NO mirror of the main contactor position. Snap-on mounts directly onto the front of a 3RH2140 or 3RH2440 auxiliary switch block, which itself snaps onto the contactor relay.
The contact ratings are given as two separate tables: a "switching current" column and a "rated value" column. The switching current table covers the range of voltages you'd see in control circuits — 6 A at 24 V, 2 A at 48 V, 2 A at 60 V, 1 A at 110 V, 0.9 A at 125 V, 0.3 A at 220 V, 6 A at 230 V, 0.3 A at 250 V, and 3 A at 400 V. The rated-value table gives the continuous thermal current (Ith) at the same voltages: 10 A at 24 V, 4.7 A at 60 V, 3 A at 110 V, 1.2 A at 220 V, 0.5 A at 440 V, and 0.26 A at 600 V. For a 24 VDC PLC output driving a contactor coil, the 6 A switching current is well above what a typical 24 VDC coil draws (usually 2-5 A inrush, <1 A sealed). The 400 V switching rating (3 A) means this block can handle pilot-duty switching on 400 VAC control transformers without welding the contacts.
Mechanical fit and mounting
Dimensions are 36 mm wide, 41.5 mm tall, 47.7 mm deep — a compact block that adds minimal width to the contactor relay stack. Snap-on mounting means no tools for installation; it clips onto the front of the base auxiliary switch block. The IP20 front protection keeps fingers away from live terminals but does not tolerate washdown — this is a dry-panel component only.
Wiring and contact reliability
Terminals accept 2x (0.5 to 2.5 mm²) solid or stranded wire, or 2x (20 to 14 AWG). For finely stranded wire with ferrules, the range is 2x (0.5 to 1.5 mm²). This block does NOT have mirror contacts per IEC 60947-4-1, so it cannot be used as a feedback contact in a safety circuit that requires mirror-contact integrity.