Siemens SIRIUS 3RT1045-1AP04-ZX95 — Size S3 Power Contactor
The Siemens SIRIUS 3RT1045-1AP04-ZX95 is a Size S3 power contactor rated for motor switching at 37 kW in AC-2 duty at 400 V, and 66 A in AC-4 duty at 400 V — meaning it handles slip-ring motor reversing and plugging without derating the main poles. The contactor carries a 45 kW rating at 500 V and 21.1 kW at 690 V, so it covers 400 V to 690 V line supplies common in European industrial panels. Snap-on mounting onto 35 mm or 75 mm DIN rail, or screw-fixed to a backplate — the 70 mm width fits standard S3 panel cutouts.
Solid wire accepted: 2x (0.5…1.5 mm²), 2x (0.75…2.5 mm²), max 2x (0.75…4 mm²). Stranded: 2x (10…50 mm²). For mixed solid/stranded runs: 2x (2.5…16 mm²). IP20 on the front with cover or box terminal; the terminal body itself is IP00 — so the panel enclosure provides the washdown seal, not the contactor.