The Siemens 3RT1016-1AH01 is a SIRIUS power contactor in the Size S00 frame, rated for 4 kW at AC-2 duty on 400 V three-phase. The 24 VDC coil pulls in at the standard 0.8 x Us and holds across the full operating range. Screw-type terminals on the main circuit accept up to 2x 4 mm² stranded, so no lug change for common motor feeds up to 4 kW. Mounts via screw or snap-on onto 35 mm DIN rail per EN 50022, with a 45 mm width that fits one standard module slot.
Panel integration is straightforward: 45 mm wide, 57.5 mm tall, 72 mm deep. Side-by-side mounting is permitted without derating in standard ambient conditions. The IP20 finger-safe front terminals mean no additional shrouding inside a closed panel. Pollution degree 3 rating suits industrial environments with conductive dust or humidity. Operating range is -25 to +60 °C, so it handles unventilated enclosures near process heat.
Compared to the 3RT1016-1AR11 (which carries a 110 VAC coil), the 1AH01 is the 24 VDC variant. Same Size S00 frame, same 45 mm width, same 4 kW AC-2 rating. The swap is a coil-voltage decision only — if your control voltage is 24 VDC, this is the one; if you're on 110 VAC, the 1AR11 drops in without rewiring the power circuit.