What this contactor is and where it fits
The Siemens 3RT1026-1AP00-ZW97 is a SIRIUS power contactor in the S0 frame size, with three normally-open main poles and screw-type terminals. It is rated for motor switching at 11 kW in AC-2 duty at 400 V, and carries the same power rating at 500 V and 690 V — so it handles standard 400 V three-phase motors and also works on 480 V or 600 V class systems without derating the power. The 45 mm wide body snaps onto a 35 mm DIN rail per EN 50022, or can be screw-mounted; side-by-side mounting is permitted with no derating gap required, which saves rail space in a multi-contactor panel.
Key ratings and what they mean for the panel
The AC-4 rating of 15.5 A at 400 V tells you the contactor can handle plugging and inching duty — frequent make-and-break under load — up to that current. For resistive or lightly inductive loads, the AC-12 maximum operating current is 10 A. The coil draws 10 A at 24 V rated value, dropping to 0.3 A at 220 V; these are the holding currents, not inrush, so size your control transformer for the inrush peak. The contactor is rated for pollution degree 3, meaning it is suited for industrial environments where conductive pollution occurs. Operating temperature range is -25 to +60 °C, with a maximum altitude of 2000 m — no derating needed for most plant-floor conditions. The front face carries IP20 finger protection; the terminals themselves are IP00, so they must be inside an enclosure.
Short-circuit coordination and wiring
For type 2 coordination (no damage to the contactor after a short-circuit), the required upstream fuse is a gL/gG 35 A. For type 1 coordination (contactor may need replacement but the installation is safe), a 100 A gL/gG fuse is allowed. The main circuit terminals accept solid or stranded conductors: 2x (0.5 to 1.5 mm²), 2x (0.75 to 2.5 mm²), or max 2x (0.75 to 4 mm²) for the control circuit; the main terminals take up to 2x 10 mm² or 1x 8 AWG. Strip length and ferrule sizing follow standard Siemens practice for screw terminals — torque to the value printed on the contactor.