SIRIUS S0 power contactor, 24 VDC coil, built-in varistor
The Siemens 3RT1026-1DB44-0KV0 is a SIRIUS power contactor in frame size S0, rated for switching motor loads up to 11 kW at 400 V in AC-2 duty (slip-ring motors, reversing) and 15.5 A at 400 V in AC-4 duty (plugging, inching). The 24 V DC magnet coil draws 5.4 W closing and holding, with a built-in varistor surge suppressor across the coil — no external snubber needed for DC switching. Screw-type terminals on the main circuit accept up to 2x 10 mm² stranded or 2x 4 mm² solid, and the two instantaneous auxiliary contacts (1 NO + 1 NC) are rated 10 A at 24 V.
Mounting and panel integration
Mounts via screw or snap-on onto 35 mm DIN rail per EN 50022. The 45 mm wide, 88 mm tall, 150 mm deep footprint fits standard S0 panel layouts. Side-by-side mounting is allowed with zero gap — no derating required for adjacent units. Pollution degree 3 (industrial environment) and IP20 on the front, IP00 at the terminals means it lives inside a closed panel, not exposed.
Coordination and protection
For Type 2 coordination (no damage to the contactor after a short circuit) the required upstream fuse is 35 A gL/gG. For Type 1 coordination (contactor may need replacement) the fuse can be 100 A gL/gG. Operating ambient range -25 to +60 °C, maximum altitude 2 000 m without derating. Mechanical life is 10 million operations typical.
Lifecycle and sourcing
This part carries a current lifecycle status. It is sourced to order against an RFQ through independent distribution channels. Availability and current pricing are confirmed at quote time. No official successor order code is recorded — this remains the active catalog number for the S0 24 VDC contactor with built-in varistor.