What it is and what it does
The Siemens SIRIUS 3RT1015-1AD01 is a size S00 power contactor built for switching motor loads and resistive loads in control panels. It snaps onto a 35 mm DIN rail per DIN EN 50022, so it fits standard panel layouts without extra brackets. The 24 VDC coil pulls in reliably across the rated control voltage range, and the screw terminals accept solid or stranded wire from 0.5 mm² up to 4 mm² — common for panel wiring.
Key ratings and what they mean for your application
The AC-4 rating of 6.5 A at 400 V is the one that matters for reversing or inching duty — those applications see arcing at each start, and this contactor is sized for it. For straight motor starting (AC-2), it handles 3 kW at 400 V and 4 kW at 690 V, so it's a solid fit for small pumps, fans, and conveyors up to about 4 kW. The 24 VDC coil draws 10 A at rated voltage; that's typical for a PLC-driven output, but watch your power supply headroom if you're ganging several contactors. The IP20 protection on the front and terminals means it's safe for finger contact inside an enclosed panel — no special covers needed for the wiring area. Pollution degree 3 is standard for industrial environments where conductive dust or condensation can occur. Operating temperature from -25 °C to +60 °C covers most control rooms and factory floors, though derating may apply if you're right at the top end with a full load.
Mounting and wiring in the panel
The 45 mm width and 57.5 mm height leave room for auxiliary contact blocks alongside. Side-by-side mounting is allowed, so you can pack multiple contactors on the same rail without a gap. The screw terminals accept two conductors per clamp — handy for daisy-chaining control wiring or paralleling power feeds. Solid wire sizes go from 0.5 mm² to 4 mm²; AWG equivalents are 20 to 14 for two wires, or 12 for a single wire.