What this contactor is and where it fits
The Siemens SIRIUS 3RT1015-1AH01-ZX95 is a size S00 power contactor rated for switching motor loads up to 4 kW at 690 V and 3.5 kW at 500 V, with a 24 VDC coil drawing 10 A at 24 V. The S00 frame is the smallest in the SIRIUS contactor family, designed for compact control panels where space is tight — 45 mm wide, 57.5 mm tall, 72 mm deep. It mounts via screw or snap-on onto a 35 mm DIN rail per EN 50022, and side-by-side mounting is permitted without derating, so you can gang multiple contactors in a row for multi-motor groups.
Key ratings — what they mean for your circuit
The AC-2 rating at 400 V gives you 3 kW for slip-ring motor duty; the AC-4 rating at 400 V delivers 6.5 A for reversing or inching applications where the contactor makes and breaks stalled rotor current. For general motor starting (AC-3), the 690 V figure of 4 kW is the headline number — that's a 4-pole induction motor up to that power on a 690 V line. The 24 VDC coil pulls 10 A inrush, then holds at a lower sealed current; the coil operating range is 0.8 to 1.1 times rated voltage at 50 Hz, 0.85 to 1.1 at 60 Hz, so it stays pulled in through brownout conditions down to about 19.2 V. The mechanical life is rated at 30 million operations, which is typical for a contactor this size — the electrical life will be lower and depends on the switching duty.
Wiring and coordination
The main power circuit uses screw-type terminals accepting 2x (0.5 to 1.5 mm²), 2x (0.75 to 2.5 mm²), or up to 2x (0.75 to 4 mm²) solid or stranded wire. For AWG, that's 2x (20 to 16), 2x (18 to 14), or 1x 12. For short-circuit protection, the manufacturer specifies a gL/gG fuse of 20 A for Type 2 coordination (no damage to the contactor) and 35 A for Type 1 coordination (contactor may need replacement after a fault). The pollution degree is 3, meaning it's rated for industrial environments with conductive pollution — no additional enclosure sealing needed for typical panel conditions. The front face carries an IP20 touch-safe rating; the terminals are also IP20, so standard finger-safe wiring practices apply.