What this contactor is and where it fits
The Siemens 3RT1317-2AN20 is a SIRIUS power contactor in frame size S00, designed for switching motor loads and resistive loads in industrial control panels. It carries four normally-open main contacts and is rated for 5.5 kW at 400 V under AC-2 duty, which covers slip-ring motor starting and plugging applications. The spring-loaded terminals accept 2x (0.25 to 2.5 mm²) solid or stranded copper, or 2x (24 to 14 AWG). Mounting is by screw or snap-on onto a 35 mm DIN rail per EN 50022, and the 45 mm width means it occupies one standard modular position in a panel layout.
What the ratings mean for your circuit
The AC-2 rating at 5.5 kW / 400 V is the motor-switching figure that governs real-world use: it confirms the contactor can handle the inrush and breaking duty of wound-rotor motors. For resistive loads (AC-12), the maximum operating current is 10 A. The contactor is also rated for DC switching at various voltages: 10 A at 24 V, 2 A at 60 V, 1 A at 110 V, and 0.3 A at 220 V — these are the current limits for breaking DC inductive circuits, which arc differently than AC. The coil operates at 50/60 Hz with a voltage tolerance of 0.8 to 1.1 times the rated value. For type of coordination 2 (limited fault damage), the required upstream fuse is gL/gG 20 A; for type 1 (no damage to persons or installation, but contactor may need replacement), it is 35 A. The pollution degree is 3, meaning the contactor is rated for conductive pollution or dry non-conductive pollution that becomes conductive due to condensation — typical for industrial control environments.
Environmental limits and enclosure considerations
Operating temperature range is -25 to +60 °C, which covers most indoor panel environments but requires derating above 40 °C per the thermal curve. The contactor is rated IP20 on the front and at the terminals, so it is touch-safe but not protected against water ingress — it must be installed inside a panel with a suitable enclosure rating. Side-by-side mounting is permitted, with a 6 mm clearance required at the side for heat dissipation. Maximum operating altitude is 2 000 m without derating. The mechanical life is 30 million operating cycles typical, which is the figure for the contactor mechanism itself; electrical life depends on the load current and switching frequency.