Siemens SIRIUS 3RT1026-1XF40-0LA2 — 110 VDC Power Contactor, S0 Frame
The Siemens SIRIUS 3RT1026-1XF40-0LA2 is a power contactor in the S0 frame size, designed for switching motor loads in industrial control panels. Its 110 VDC coil includes an integrated varistor surge suppressor, and the contactor mounts via screw or snap-on onto 35 mm DIN rail per DIN EN 50022. The DC coil draws a pickup power of 0.7 per-unit initial value and a holding power of 1.25 per-unit full-scale value, meaning the coil's inrush is lower than its sealed consumption — a characteristic that simplifies DC supply sizing in 24 VDC or 110 VDC control circuits. Rated for AC-4 duty at 15.5 A at 400 V, this contactor handles the severe switching conditions of plugging and inching motor loads, not just steady-state running. The operating temperature range of -40 to +70 °C covers unheated enclosures and high-ambient panel interiors.
Panel Integration & Wiring
The S0 frame occupies 45 mm width on the DIN rail, with a depth of 101 mm and height of 116 mm. Clearance requirements: 10 mm upwards, 10 mm forwards, 10 mm downwards, and 10 mm at the side — tight enough for dense panel layouts but verify against adjacent devices. Main circuit terminals accept screw-type connections: solid conductors 2x (0.5...1.5 mm²), 2x (0.75...2.5 mm²), max. 2x (0.75...4 mm²). Auxiliary/control circuit terminals accept 2x (1...2.5 mm²) solid or stranded, max. 2x 10 mm². Side-by-side mounting is permitted, which saves rail space when grouping multiple contactors.
Switching Capacity & Motor Ratings
The main contact rated impulse withstand voltage is 6 kV, consistent with standard industrial isolation coordination. Motor horsepower ratings span from 2 hp at 110/120 V up to 20 hp at 575/600 V, covering common North American motor voltages. At 400 V the contactor switches 11 kW motors; at 690 V it also switches 11 kW. DC switching ratings are provided for the auxiliary contacts: 10 A at 24 V, 2 A at 60 V, 1 A at 110 V, and 0.3 A at 220 V. These matter when the contactor controls DC solenoids or indicator lamps in the same panel.
Compliance & Substance Restrictions
The product carries a substance prohibition date of 05/01/2012, referencing RoHS and REACH compliance milestones. Standard Siemens SIRIUS documentation includes the declaration of conformity and the CE mark; specific UL or IEC certification files are available on request.