Reversing contactor assembly — what's in the box
The 3RA9012-5AY25 is a Siemens reversing contactor set, 3-pole, rated 115 A, with a 24 VDC coil. It ships as a GM-SET assembly — two contactors mechanically interlocked for direction reversal, each with 2NO-2NC auxiliary contacts and a coil suppressor across the coil terminals.
What the 115 A and 24 VDC coil mean for fit
115 A is the rated operational current — sized for reversing motor loads up to roughly 55 kW at 400 V AC-3 duty, depending on the motor full-load amps. The 24 VDC coil keeps the control circuit separate from the power side, which simplifies compliance with machine safety circuits that run on 24 VDC. The integrated coil suppressor (a varistor or RC snubber) limits voltage spikes when the coil de-energises, protecting the PLC output driving it.