The Siemens SIRIUS 3RT1026-1AL20-ZW96 is a Size S0 power contactor rated for 11 kW motor loads at 400 V in AC-2 duty — the kind of switching that handles slip-ring motors or wound-rotor drives where starting current is managed, not just slammed on. It's a screw-terminal unit with an IP20 front face, meaning the terminals themselves are touch-safe once wired, but the contactor is meant for a clean, enclosed panel, not a washdown zone. Side-by-side mounting is allowed with no derating gap, so you can pack several in a row without losing thermal headroom.
Rated for 11 kW at 400 V AC-2, this contactor handles motor loads that pull starting current but don't need the full AC-3 or AC-4 interrupting capability. In a cement plant, that fits preheater fan drives or clinker conveyor motors that start under partial load. The AC-4 rating of 15.5 A at 400 V tells you the contactor can also manage plugging or inching duty — reversing or jogging a motor under load — though at a lower power than its AC-2 rating. Pollution degree 3 rating confirms design for conductive dust environments. That's a clean, standard spec that any panel builder can implement without special fusing.
Wiring and auxiliary contacts
Main circuit terminals accept 2x (1 to 2.5 mm²) stranded, 2x (2.5 to 6 mm²), or up to 2x 10 mm² — solid or ferruled. The auxiliary contact block (included in the -ZW96 variant) handles 24 V DC at 10 A, 60 V DC at 2 A, and 230 V AC at 6 A, which covers most PLC output signals and pilot devices on a standard control circuit.
If you're replacing a 3RT1023-1AL20 (smaller S0 frame, lower rating), check your motor load: the 3RT1026 carries 11 kW AC-2 versus the 1023's lower rating, so it's an upgrade in capacity but shares the same 45 mm footprint and terminal layout.