SIRIUS Vacuum Contactor, Size S10
The Siemens 3RT1266-6AU36 is a SIRIUS vacuum contactor in the Size S10 frame. The sealed vacuum chamber extinguishes the arc in 10-15 ms with no contact erosion. The 240-277 V AC coil pulls in at 80% of rated voltage and operates across 40-80 ms on both AC and DC. Mounting is by screw fixing with a single 11 mm hole. The contactor accepts stranded cable from 70 to 240 mm² on the main power path, and solid or stranded control wiring in sizes from 0.5 to 4 mm². The auxiliary switch is present and the coil connection uses screw-type terminals.
Ratings & Fit
The auxiliary contact ratings define the signal-level switching capability: 10 A at 24 V, 2 A at 48 V, 2 A at 60 V, and 1 A at 110 V. These are the maximum continuous currents the auxiliary contacts can break — important when driving PLC inputs, relay coils, or indicator lamps in the control circuit. The main power contacts are rated for the Size S10 frame; the 70-240 mm² stranded cable range indicates a contactor sized for motor loads in the 100-200 A range, typical for large pumps, compressors, or conveyors on 400 V three-phase systems. Dimensions: 210 mm height, 145 mm width, 206 mm depth. The depth of 206 mm is the dimension from the mounting surface to the furthest projection — critical for enclosure depth planning, especially when a panel door or busbar system is close behind the mounting plate.