SIRIUS S2 power contactor for motor loads
The Siemens 3RT1035-1AP60 is a SIRIUS S2-frame power contactor rated 22 kW at 500 V AC-3 and 18.5 kW at 400 V AC-2. That AC-3 duty rating is the one you care about for standard squirrel-cage motor starting — it tells you the contactor can make and break locked-rotor current without welding the main poles. AC-2 covers slip-ring motors where the inrush is lower but the switching cycle is more frequent. It mounts on a 35 mm DIN rail per EN 50022, screw or snap-on, and takes up 55 mm of rail width. The screw-type main terminals accept stranded up to 25 mm² and solid up to 4 mm² per clamp. Coil draw at 24 V rated value is 10 A — that's the pick-up surge, not the hold-in; the sealed coil current will be lower. At 230 V rated value the auxiliary contacts handle 6 A.
What the ratings mean on the line
The AC-3 rating of 22 kW at 500 V is the headline number for a sourcing decision: it means the contactor can switch a 22 kW motor on a 500 V three-phase line through its full load and break stall current. At 400 V the same contactor is rated 18.5 kW AC-2, so if your motor is 400 V and slip-ring, that's your limit. The AC-1 resistive rating is not listed here, but the 1 200 operations per hour maximum at AC-1 suggests it can handle higher resistive currents — just not at the same switching rate as motor duty. Mechanical life is 10 million operations typical. Electrical life depends on the load — at AC-3 the contactor is rated for 1 000 operations per hour, at AC-4 (plugging/inching) it drops to 300 per hour. The arcing time runs 10 to 15 ms, and the pick-up/drop-out time at AC is 7 to 20 ms. That's fast enough for most line-starter applications but worth checking if you're sequencing contactors in a reversing or star-delta circuit.
Mounting and wiring in the panel
This is a screw-and-snap-on mount for 35 mm DIN rail per EN 50022. Side-by-side mounting is allowed, so you can pack contactors tight on the rail — no mandatory spacing gaps. The 55 mm width and 112 mm height are standard S2 frame dimensions. Depth is 115 mm, which means it clears most 200 mm deep enclosures with room for the outgoing cables. Terminals are screw-type for the main circuit. The solid wire range is 2x (0.5 to 1.5 mm²) and 2x (0.75 to 2.5 mm²), with a maximum of 2x (0.75 to 4 mm²) per clamp. Stranded main wires go up to 2x (0.75 to 25 mm²). That's generous for a 22 kW contactor — you can land 16 mm² or 25 mm² without a ferrule if the lug is rated for it. The enclosure front is IP20; the terminal area is IP00, so install it inside a panel with a door or cover.