What it is and what it does
The Siemens 3RT1017-1AV61 is a SIRIUS power contactor in the compact S00 frame size, designed for switching motor loads and resistive circuits in control panels. It carries three normally-open (NO) main contacts rated for 10 A at 24 V resistive (AC-12) and delivers 5.5 kW at 400 V in AC-2 duty — the category for slip-ring motor starting and switching. For reversing or plugging duty (AC-4), it handles 8.5 A at 400 V, so it can manage frequent inching or jogging cycles without derating the main contacts. The 24 VDC coil holds in across the rated operating range, and the contactor mounts via screw or snap-on onto a 35 mm DIN rail per DIN EN 50022 — standard for any European-style panel. At 45 mm wide and 57.5 mm tall, it fits the S00 footprint, leaving room for auxiliary contact blocks on the side.
What the ratings mean on the line
The AC-2 rating at 5.5 kW / 400 V is the number that governs motor switching for wound-rotor or slip-ring motors — common in crane and hoist applications where starting current stays under 2.5x full load. For standard squirrel-cage motors, the AC-3 rating (not listed here) would be the usual selection, so verify your motor starting method if you are replacing a general-purpose contactor. The AC-4 rating of 8.5 A at 400 V matters for reversing or jogging duty. If your application cycles the contactor under load more than a few times per hour, this is the current limit — not the AC-2 figure. Exceeding it accelerates contact wear and risks welding. Pollution degree 3 means the contactor is rated for conductive pollution or dry non-conductive pollution that becomes conductive due to condensation — typical in industrial enclosures without climate control. The IP20 front protection keeps fingers and tools out, but the contactor needs to be inside a cabinet for washdown environments. Operating temperature from -25 to +60 °C covers most machine-room and outdoor cabinet conditions. The altitude limit of 2000 m is standard for low-voltage switchgear — above that, dielectric strength and air clearance derate, so factor that in for high-altitude installations.
Wiring and coordination
Main circuit terminals are screw-type, accepting 2x (0.5 to 1.5 mm²) or 2x (0.75 to 2.5 mm²) solid/stranded, with a maximum of 2x (0.75 to 4 mm²). AWG equivalents are 2x (20 to 16) and 2x (18 to 14), with a single 12 AWG also accepted. Strip length and torque are standard for S00 screw terminals — no special tooling needed. For Type 2 coordination (no damage to the contactor under short circuit), the required upstream fuse is a gL/gG 20 A. Type 1 coordination (contactor may need replacement but no fire risk) allows a 35 A gL/gG fuse. These fuse ratings define the maximum short-circuit protection the contactor can withstand — match them to your panel's SCCR calculation. Side-by-side mounting is permitted without derating, which saves rail space in multi-contactor panels. The 6 mm clearance to adjacent devices on the side is the minimum for heat dissipation.