SIRIUS Size S00 power contactor — 4 NO, spring terminals
The Siemens 3RT1316-2BA40 is a SIRIUS power contactor in the Size S00 frame, with four normally-open main contacts and spring-loaded terminals for the main current circuit. It's rated for 4 kW at 400 V in AC-2 duty (slip-ring motor switching), and carries a 10 A rated value at 24 V for the magnet coil. The contactor snaps onto a 35 mm DIN rail per DIN EN 50022, or can be screw-mounted — standard panel integration for a 45 mm wide device.
Ratings and what they mean for fit
The 4 kW AC-2 rating at 400 V tells you this contactor is sized for wound-rotor motor loads up to that power — AC-2 covers starting and plugging duty, not just steady running. The 10 A at 24 V coil rating means the control circuit needs a supply capable of that inrush; holding power is 3.3 W DC, so once pulled in the coil draw drops sharply. Mechanical endurance is spec'd at 30 million operating cycles, which aligns with high-cycle applications like conveyor or pump stations. For coordination, Type 2 coordination requires a 20 A gL/gG fuse; Type 1 allows a 35 A gL/gG fuse. That's the overcurrent protection the installer needs to match for short-circuit ratings. Operating temperature range is -25 to +60 °C, and the front face carries IP20 protection — suitable for enclosed panel mounting, not open washdown areas.
Mounting and wiring
Spring-loaded terminals accept 2x (0.25 to 2.5 mm²) solid or stranded, or 2x (0.25 to 1.5 mm²) finely stranded with ferrule. AWG equivalents are 2x (24 to 14). The 72 mm depth, 45 mm width, and 60 mm height fit standard S00 panel layouts. Side-by-side mounting is allowed — no derating gap required — with a 6 mm clearance to adjacent devices at the side. Maximum operating altitude is 2,000 m without derating.