SIRIUS S6 power contactor – 200–277 V AC coil, screw terminals
The Siemens 3RT1054-1SP36-3PA0 is a SIRIUS power contactor in frame size S6, designed for switching motor loads in industrial control panels. The coil is rated 200–277 V AC, meaning it pulls in reliably across the European 230 V line and North American 277 V lighting circuits without an external transformer. Screw-type coil terminals and stranded cable acceptance up to 70 mm² make this a straightforward replacement in existing screw-terminal panels.
Ratings and what they mean for the panel
MTBF is listed at 75 a — that's 75 years mean time between failures under stated operating conditions, which translates to a maintenance interval measured in decades for a correctly sized installation. The contactor is rated for AC-3 switching at up to 750 operations per hour, covering most motor start/stop cycles on conveyors and pumps. AC-4 duty (plugging, inching) is limited to 130 ops/h — relevant if the application does frequent reversing. Mechanical endurance is 10,000,000 operations typical, so the wear-out limit is the electrical load, not the mechanism. The auxiliary switch is built in, saving a separate add-on block for status feedback to the PLC. Mounting is screw fixing onto a vertical surface, rotatable ±90° and tiltable ±22.5°. Clearances: 10 mm above/below/sides, 20 mm forward — standard for a contactor of this size in a ventilated enclosure.