What this auxiliary switch does on a 3RT1 contactor
The 3RT1926-2EC21: The delay is adjustable from 0.5 to 10 seconds, set via a potentiometer on the block. Recovery time between cycles is 150 ms, which governs how quickly the delay can be re-triggered after the coil drops out.
Contact ratings and wiring
The switch contacts are rated 3 A maximum, with voltage-dependent derating: 1 A at 24 V, 0.2 A at 125 V, and 0.1 A at 250 V. These are the continuous current limits for the auxiliary circuit — typically a PLC input, a signal lamp, or a small relay coil. The block is 33 mm wide and 46 mm tall, with a depth of 73 mm when mounted on the contactor.
Clip-on fastening snaps directly onto the contactor without tools. Pollution degree 3 with basic insulation — suitable for standard industrial control panels where conductive dust or humidity is present.