Siemens SIRIUS 3RT1026-1AG20-ZW96 — S0 Power Contactor for Motor Loads
The Siemens SIRIUS 3RT1026-1AG20-ZW96 is a size S0 power contactor rated for 11 kW at 400 V in AC-2 duty, meaning it handles standard squirrel-cage motor starting and stopping within that power band. The AC-4 rating of 15.5 A at 400 V covers reversing, plugging, or inching applications where the contactor makes and breaks stalled-rotor current. The coil is 24 VDC, and the contactor mounts via screw or snap-on onto 35 mm DIN rail per DIN EN 50022, fitting into standard industrial control panels.
Key Ratings and What They Mean for Fit
The AC-2 rating at 400 V (11 kW) is the headline motor-switching spec — it confirms the contactor can handle a 11 kW induction motor on 400 V three-phase without excessive contact wear. The AC-4 current (15.5 A) is the limiting figure for high-stress duty cycles: if your application requires frequent reversals or inching, size the motor load so the starting current stays under 15.5 A. The operating current at AC-12 (10 A) applies to resistive or lightly inductive loads like heaters or transformers, not motor duty. The contactor carries a mechanical life of 10 million operations, typical for the S0 frame, and operates from -25 °C to +60 °C, so it holds up in unheated enclosures or near hot machinery. Pollution degree 3 means it's rated for conductive pollution environments — typical of factory-floor panels.
Mounting and Wiring in the Panel
The 3RT1026-1AG20-ZW96 is 45 mm wide, 85 mm tall, and 91 mm deep — a compact S0 footprint that leaves room for auxiliary contact blocks or overload relays on the same DIN rail. Side-by-side mounting is allowed with 6 mm spacing between units, which helps with heat dissipation and terminal access. Screw terminals on the main circuit accept 2x (0.75 to 4 mm²) solid or stranded, and up to 2x 10 mm² for the main conductors — enough for the 11 kW motor feed. The front face is IP20, the terminal area is IP00, so the contactor must be mounted inside an enclosure that provides the final IP rating.