What this contactor is and where it fits
The Siemens 3RT1024-3XG28-0MV0-ZW97 is a SIRIUS S0-frame power contactor with a 110 V 50/60 Hz coil, screw-type terminals for the main circuit, and an integrated RC surge suppressor. It's rated for motor switching at 7.5 kW at both 500 V and 690 V, and delivers 12.5 A in AC-4 duty at 400 V — the heavy jogging and inching category. The S0 frame means it occupies a 45 mm wide DIN-rail footprint and snaps onto 35 mm rail per DIN EN 50022, so it drops into a standard panel layout without surprises.
Key ratings and what they mean for the buyer
The AC-2 rating at 400 V is 5.5 kW — that's the slip-ring motor duty where the contactor makes and breaks the rotor circuit under load. For AC-4 at 400 V, the rated operational current is 12.5 A, which covers plugging and inching of squirrel-cage motors. The AC-12 rating (control-circuit resistive load) is 10 A. The two built-in auxiliary contacts (instantaneous) handle 10 A at 24 V, 6 A at 230 V, and 3 A at 400 V, so they can drive small contactors or PLC inputs directly without an interposing relay. The coil holds in at 0.8 to 1.1 times rated voltage at 50 Hz, and 0.85 to 1.1 at 60 Hz. That's a standard operating range — expect dropout below about 88 V at 50 Hz. The RC suppressor is built in, so you don't need an external snubber for the coil; just watch polarity if you're feeding DC to the coil (this is an AC coil). Ambient operating range is -25 to +60 °C, with pollution degree 3 (conductive pollution or dry non-conductive that becomes conductive). That's typical for industrial control panels — no derating needed for most factory-floor environments. Maximum operating altitude is 2 000 m.
Mounting and wiring
Mounts by screw or snap-on onto 35 mm DIN rail per EN 50022. Side-by-side mounting is permitted — no gap required between contactors. The screw terminals for the main circuit accept 2x (0.25 to 2.5 mm²) solid, 2x (1 to 2.5 mm²) stranded, 2x (2.5 to 6 mm²) stranded, or up to 2x 10 mm². For AWG: 2x (16 to 12), 2x (14 to 10), or 1x 8. The front has IP20 finger protection; the terminal area itself is IP00 — keep tools and fingers clear when live. With type of coordination 2, the required upstream fuse is gL/gG 25 A. That's the standard short-circuit protection for this frame size — it lets the contactor survive a fault without welding the main contacts.