What it is and what it does
The Siemens 3RT1016-1HB41 is a SIRIUS power contactor in the compact size S00 frame — the smallest footprint in the SIRIUS contactor family, at 45 mm wide, 57.5 mm tall, and 72 mm deep. It's built for switching motor loads in control panels: rated 4 kW at 400 V in AC-2 duty (slip-ring motors, moderate inrush) and 8.5 A at 400 V in AC-4 (plugging, inching, reversing). The 24 VDC coil draws 2.3 W to pull in and holds at the same power — no separate hold-in economizer needed, which simplifies the control transformer sizing.
Coil ratings and switching capacity
The DC coil is rated for continuous duty across the operating range of -25 °C to +60 °C. Switching capacity at 24 VDC is 10 A; at 60 VDC it drops to 2 A, at 110 VDC to 1 A, and at 220 VDC to 0.3 A — the inductive load curve matters here, so don't expect the 24 A figure to hold at higher voltages. For the main power circuit, the screw-type terminals accept 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 — plenty of room for motor power leads up to 4 kW.
Mounting and integration
Snaps onto a 35 mm DIN rail per EN 50022, or can be screw-mounted. Side-by-side mounting is allowed with 6 mm clearance to adjacent devices — that's tight enough for high-density panel layouts. IP20 on the front and at the terminals means it's protected against finger contact but not washdown — keep it inside a closed panel, not out on the wet floor.
Coordination and protection
Type 1 coordination requires a 35 A gL/gG fuse upstream; Type 2 coordination needs a 20 A gL/gG fuse. That's the maximum short-circuit protection the contactor can ride through without welding its main contacts — size your branch circuit protection accordingly. Pollution degree 3 (industrial environment, conductive dust or condensation) is the rated environment — standard for most factory-floor control panels.