SIRIUS 3RT7025-1AH05 — 3-Pole Contactor, AC Coil, S0 Frame
The Siemens 3RT7025-1AH05 is a 3-pole contactor from the SIRIUS family, in the S0 frame size, with an AC coil and screw-type terminals for both main and auxiliary circuits. Rated for AC-3 duty up to 690 V, it switches 6 A at 230 V, 3 A at 400 V, and 1 A at 690 V — covering motor loads in the fractional-to-small-horsepower range. The AC coil draws 0.82 W closing power and holds at 0.24 W, so the control transformer or PLC output must supply that inrush transient. Auxiliary contacts are rated for PLC-level reliability (17 V, 5 mA), meaning they can switch low-energy signals without oxide-film issues.
Mounting and Integration
Mounts via screw or snap-on onto 35 mm DIN rail per DIN EN 50022. The S0 footprint is 55 mm wide, 85.5 mm tall, and 91 mm deep — a compact block that fits standard panel layouts. Side-by-side mounting is allowed with no derating gap, so multiple contactors pack tightly on the rail. The mounting position allows ±180° rotation on a vertical surface and ±22.5° tilt forward/backward. IP20 on the front and terminals means finger-safe protection inside an enclosed panel — not for washdown or outdoor exposure.
Coordination and Protection
For Type 2 coordination (minimal contact damage on fault), the required upstream fuse is a gL/gG NH 3NA: 25 A. For Type 1 coordination (contactor may need replacement after fault), the fuse rating is 63 A. Rated insulation voltage is 690 V, with surge voltage resistance at 6 kV — suitable for 400 V line-to-line systems with adequate clearance. Pollution degree 3 means it's rated for industrial environments with conductive or dry non-conductive pollution.