What it is and what it does
The Siemens 3RT1017-1AQ64 is a SIRIUS power contactor in the compact S00 frame size, designed for switching motor loads and resistive loads in industrial control panels. It mounts on a 35 mm DIN rail per DIN EN 50022, either snapped on or screwed down, and allows side-by-side mounting to save panel width — each unit takes 45 mm of rail space. The 24 VDC coil pulls in reliably across a 0.85 to 1.1 times rated voltage at 50 Hz and 0.8 to 1.1 at 60 Hz. At 24 V the main contacts are rated 10 A; for motor duty at 500 V it handles 5.5 kW, and at 690 V also 5.5 kW. The AC-4 rating at 400 V is 8.5 A — that's the switching category for reversing or inching duty where the contactor makes and breaks stalled rotor current. Front protection is IP20, so it's safe for finger contact inside an enclosed panel. Pollution degree 3 means it's rated for conductive pollution environments typical of industrial floors — no special coating needed for most factory air.
What the ratings mean for fit
The 10 A rating at 24 V is the maximum thermal current (AC-12) for the main contacts — that's the resistive load limit. For motor starting (AC-3), the practical limit is the 5.5 kW figure at 500 V or 690 V. If you're switching a 4 kW motor on a 400 V line, this contactor has headroom. The AC-4 rating of 8.5 A at 400 V tells you the contactor can handle frequent plugging or jogging without welding contacts — useful for crane drives or conveyor reversers. Short-circuit coordination is specified: type 2 coordination requires a gL/gG fuse rated 20 A; type 1 coordination allows a 35 A fuse. That means with a 20 A fuse upstream, the contactor remains usable after a fault (type 2). With 35 A, the contactor may need replacement after a fault (type 1). Pick your fuse based on whether downtime for contactor swap is acceptable. Mechanical endurance is 30 million switching cycles — that's the contactor body life before wear-out, not the electrical life under load. Electrical life depends on the switched current and category; for a 5.5 kW motor started once per minute, expect several hundred thousand operations before contact inspection.
Integration notes
Terminals are screw-type for the main circuit, accepting 2x (0.5 to 1.5 mm²), 2x (0.75 to 2.5 mm²), or max 2x (0.75 to 4 mm²) solid or stranded wire. AWG equivalents are 2x (20 to 16), 2x (18 to 14), or 1x 12. Strip length is standard for the terminal design — no special tooling needed beyond a screwdriver. Operating temperature range is -25 to +60 °C, so it's fine for unheated cabinets in cold climates as long as the cabinet stays above -25. Maximum operating altitude is 2 000 m without derating; above that, air density drop reduces the contactor's interrupting capacity. The contactor has 2 instantaneous auxiliary contacts (form C or form A depends on the specific variant — check the full order code suffix for the auxiliary configuration). These are rated for switching at various voltages: 10 A at 24 V, 2 A at 60 V, 1 A at 110 V, 0.3 A at 220 V, 6 A at 230 V, 3 A at 400 V.