The Siemens SIRIUS 3RT1054-6SF36-3PA0 is a Size S6 power contactor built for switching motor loads in industrial control panels. It carries a 96-127 VAC coil with screw-type terminals and includes an integrated auxiliary switch block. The MTBF of 75 a reflects a design meant to survive the nacelle — no up-tower swaps on a wind turbine pitch system when you spec this one right.
What the Ratings Mean for Fit
The coil operates at 96-127 VAC. Pickup and dropout timing is 115-130 ms for both AC and DC. Rated for AC-1 at 750 operations per hour and AC-3 at 750 ops/h, this contactor handles high-duty-cycle motor starting — conveyors, pumps, compressors cycling every few seconds. AC-4 drops to 130 ops/h, which is the plugging and inching limit; if you're reversing a load frequently, that 130 ops/h ceiling is the real constraint, not the AC-3 number. Arcing time of 10-15 ms is tight — the arc extinguishes fast inside the Size S6 arc chamber, which matters for contact life on inductive motor breaks. Typical mechanical life is 10 million operations, so this part is rated for the shake in high-cycle applications like material handling or wind turbine yaw drives. Operating temperature range of -25 to +60 °C covers unheated enclosures in northern climates and hot panel interiors near drives. Storage range of -55 to +80 °C means it survives shipping in a frozen truck or a container sitting in the sun.
Mounting and Wiring in the Panel
Fastens with screw fixing through a single 9 mm hole — not a DIN-rail snap-on, so plan for a drilled backplate. Mounting position is flexible: vertical surface with +/-90° rotation and +/-22.5° tilt front-to-back, which helps when you're fitting this into a tight corner of an MCC bucket. Main power terminals accept stranded wire from 25 to 120 mm² — that's the heavy lug range for motor feeders up to maybe 200-300 A depending on duty. Auxiliary and coil terminals take solid or stranded 0.5-1.5 mm², 0.75-2.5 mm², or max 0.75-4 mm² — standard control wiring with ferrules. The auxiliary switch is rated 10 A at 24 V, 2 A at 48 V, and 2 A at 60 V, so it handles PLC-level signals and small relay loads without an interposer. Dimensions: 172 mm high, 120 mm wide, 170 mm deep. Clearance requirements: 10 mm upward, 20 mm forward, 10 mm downward, 10 mm at the side — allow those for arc flash and heat dissipation. The Size S6 frame is substantial; verify swing clearance for the arc chamber before you lay out the gland plate.