The Siemens 3RT1046-3AH00 is a SIRIUS power contactor in the Size S3 frame, rated for 55 kW at 500 V and 80 A in AC-4 duty at 400 V.
Snaps onto 35 mm or 75 mm standard mounting rail — the 75 mm option is less common but saves a rail adapter on heavy-gauge panels. Dimensions are 146 mm high, 70 mm wide, 139 mm deep — the 70 mm width is the S3 standard, so it occupies one slot in a typical 600 mm enclosure grid. IP20 on the front with the cover installed; the terminal area is IP00, meaning the live parts are exposed until the enclosure door is closed.
Duty ratings and thermal limits
AC-1 (resistive) allows 900 operating cycles per hour; AC-3 (motor start) allows 850; AC-4 (reversing/inching) drops to 250.