What it is and what it does
The Siemens 3RT1017-1AR61 is a SIRIUS power contactor in the compact S00 frame, with an AC-2 rating of 5.5 kW at 400 V and an AC-4 rating of 8.5 A at 400 V for reversing or jogging duty. It snaps onto a 35 mm DIN rail per EN 50022 and measures 45 mm wide by 57.5 mm tall by 72 mm deep — a footprint that fits tightly packed panels where every millimeter of DIN rail space is accounted for. The screw-type terminals accept solid or stranded conductors from 0.5 mm² up to 4 mm² (2x per terminal), and the front face carries an IP20 rating for basic finger-safe touch protection in an enclosure.
Key ratings and what they mean for your panel
The AC-12 rating of 10 A covers resistive loads like heaters or lighting ballasts — not motor starting, but useful for auxiliary contactor duty or general switching. The AC-4 8.5 A at 400 V matters when you need to reverse or plug the motor — that's the worst-case current the contacts see during inching or counter-torque braking. Pollution degree 3 means it's designed for industrial environments where conductive dust or occasional condensation is expected — not a clean-room part, but fine for most factory floors. The operating temperature range of -25 to +60 °C covers unheated warehouses and hot cabinet interiors alike, though the contactor's 30 million typical mechanical cycles assume you stay within that band.
Coil and control circuit specifics
The coil operates at 50/60 Hz with a voltage tolerance of 0.85 to 1.1 times rated, and the holding currents are listed per voltage: 10 A at 24 V DC, 2 A at 60 V DC, 1 A at 110 V DC, 0.3 A at 220 V DC, 6 A at 230 V AC, and 3 A at 400 V AC — these are the steady-state draws your PLC output or relay must supply once the contactor is sealed in. With a single instantaneous contact (1 NO or 1 NC depending on wiring), the 3RT1017-1AR61 gives you one feedback signal to the controller — enough for a run-status indication, but not for separate on/off confirmation without an auxiliary contact block.
Coordination and protection
For Type 2 coordination (no damage to the contactor after a short circuit), Siemens specifies a 20 A gL/gG fuse upstream. For Type 1 coordination (contactor may need replacement after fault), a 35 A gL/gG fuse is allowed — this matters when you're sizing the branch circuit protection for a motor starter. Side-by-side mounting is permitted without derating, so you can pack multiple S00 contactors on the same DIN rail at 6 mm spacing between units — common in a motor control center or pump panel.