The Siemens 3RT1023-1BE40 is a SIRIUS power contactor in Size S0, designed for switching motor and resistive loads in control panels. It mounts via screw and snap-on onto 35 mm DIN rail per DIN EN 50022, with a 45 mm width that fits standard panel layouts. Rated 10 A in AC-12 duty, so it handles resistive and lightly inductive loads up to that current. For motor switching, it delivers 4 kW at 400 V in AC-2 (slip-ring motor start/run) and 8.5 A at 400 V in AC-4 (plugging/inching). DC switching is covered: 10 A at 24 V, 2 A at 60 V, 1 A at 110 V, 0.3 A at 220 V — useful for battery-backed or DC distribution circuits.
Integration Notes
Screw-type terminals on the main current circuit accept 2x (1 to 2.5 mm²) or 2x (2.5 to 6 mm²) stranded, up to 2x 10 mm². The auxiliary circuit uses 2x (0.5 to 1.5 mm²) or 2x (0.75 to 2.5 mm²) solid, max 2x (0.75 to 4 mm²). Side-by-side mounting is allowed with 6 mm spacing at the side for heat dissipation. IP20 on the front, IP00 at the terminals — panel builders should account for terminal protection in the enclosure design. Coil holding power is 5.4 W DC, and the magnet coil draws the same closing power. Pollution degree 3 suits industrial environments with conductive contamination.