Siemens 3RT1026-1AG20-ZI41W96 Contactor — Integrator's Spec Recap
The Siemens 3RT1026-1AG20-ZI41W96 is a SIRIUS 3RT1 contactor rated AC-3 at 11 kW on 400 V three-phase — that's the motor-switching duty for a 15 HP class induction motor at 400 V. Coil is 110 V AC 50/60 Hz, so it pulls in on standard control transformer secondaries across the panel. Three poles, size S0 frame, screw terminals on both line and load sides. The -ZI41W96 suffix denotes a special version with reusable packing in a 96-unit pack — the contactor itself is standard electrically.
What the AC-3 11 kW Rating Means for Motor Switching
The AC-3 duty class covers starting and switching off squirrel-cage motors under load. At 400 V, the 11 kW rating corresponds to roughly 22 A making and breaking current — the contactor is designed to handle the inrush (typically 6–8× FLA) during start and interrupt the running current without welding or excessive arc erosion. This is a standard S0 frame rating; the same physical contactor can be applied at higher currents in AC-1 resistive duty (typically around 32 A), but the AC-3 figure is the one that governs motor applications.
Panel Integration: Size S0 DIN Rail Mount
Size S0 snaps onto standard 35 mm DIN rail per EN 60715. The 3-pole block occupies roughly 45 mm of rail width — plan for that footprint plus the required clearance for screwdriver access on the line/load terminals. Screw terminals accept up to 4 mm² stranded or 6 mm² solid; torque to 1.2–1.5 Nm. The 110 V AC coil draws about 5 VA holding, so a 50 VA control transformer can feed several contactors in a group.