The Siemens 3RT1316-1BG40 is a SIRIUS power contactor in frame size S00 — the smallest in the series, designed for switching motor loads and resistive loads in control panels up to 4 kW at AC-2 duty on a 400 V line. It carries four normally-open main contacts rated 10 A in AC-12 (control-circuit duty), so it can also serve as a high-current interposing relay in PLC output circuits. The 24 VDC coil draws 3.3 W both on pickup and hold, which simplifies the DC supply budget — no inrush spike to size for.
The main contacts are screw-type terminals accepting 2x 0.75 to 4 mm² solid or stranded, or 2x 20 to 14 AWG, with a single 12 AWG also allowed. The auxiliary contact ratings cover 10 A at 24 V down to 0.3 A at 220 V DC, which covers most DC control circuits in industrial panels.
At 72 mm deep, 57.5 mm tall, and 45 mm wide, the S00 frame fits standard 45 mm pitch DIN-rail layouts. The screw terminals are accessible from the front, so wiring in a dense row is straightforward. The coil holding power is the same as the closing power — 3.3 W DC — which means no additional heat sink or derating for continuous energization. For a 24 VDC supply, that is about 137 mA continuous draw per contactor.