What It Is and Where It Fits
The Siemens 3RT1024-1AP04 is a SIRIUS power contactor in the S0 frame size, with three normally-open main contacts and zero NC main contacts. Screw-type terminals on both main and control circuits accept up to 2x 10 mm² on the mains and 2x 4 mm² on the aux/control side. The front face is rated IP20, the terminals are IP00.
Mounting and Panel Integration
Mounts via screw or snap-on onto standard 35 mm DIN rail per EN 50022. The S0 footprint is 45 mm wide by 85 mm tall by 140 mm deep — that depth is the dimension to watch when laying out the enclosure depth, especially with duct or side-mounted auxiliaries. Side-by-side mounting is allowed with no derating gap, so you can pack a row of these tight on the rail for multi-motor groups. Pollution degree 3 rating means it's suited for industrial environments with conductive pollution; no conformal coating required for normal panel conditions.
Ratings That Matter for the Buyer
The AC-3 motor-switching rating at 500 V is 7.5 kW, and the same at 690 V — that's the headline number for sizing to a standard three-phase induction motor. For DC switching, the 24 V DC rating is 10 A, which covers most control transformer or solenoid loads. The AC-4 rating at 400 V is 12.5 A — that's the inching or plugging duty cycle rating; if the application involves frequent reversing or jogging, this is the current limit to design to, not the AC-3 number. Rated operational current for AC-12 (resistive) is 10 A maximum. Ambient operating range is -25 to +60 °C, which covers most unventilated panel interiors.