The 3RT7025-1AC25 is a size S0 contactor — 55 mm wide, 85.5 mm tall, 91 mm deep — that screws or snaps onto a 35 mm DIN rail per EN 50022. Screw terminals on both the main and auxiliary circuits accept up to 2x 2.5 mm² solid or stranded, or 2x 1.5 mm² with ferrules.
Three normally-open main contacts, rated for AC-3 switching up to 690 V maximum. At 230 V the contactor carries 6 A; at 400 V it's 3 A; at 690 V it's 1 A. Those are the motor-switching currents — the numbers that tell you whether this contactor will hold in on a pump or conveyor start. The coil is 24 V AC, 50/60 Hz, drawing 0.24 A at both frequencies. Closing power on DC is 0.72 W; holding power drops to 0.24 W — the economizer circuit cuts the hold-in current once the armature seats. Surge voltage withstand is 6 kV, which covers the impulse levels you see in a standard 400 V industrial distribution. Mechanical switching frequency: 800 operations per hour max under AC-3 duty, 250 per hour under AC-4 (plugging/reversing). Shock resistance is 12.5g for 5 ms or 7.8g for 10 ms — enough for most machine-mounted panels but not for direct engine-block mounting.
For BOM planning: the contactor carries IP20 on the front and at the terminals — it's a panel-interior part, not a field-mounted device. Fuse coordination: for type 2 coordination use a 25 A gL/gG NH 3NA fuse; for type 1 coordination use 63 A.