Panel fit and what the ratings actually mean
The 3RT2026-1AL20-ZW96: If you gang several contactors side-by-side, plan for that 6 mm gap between units so the arc chutes can breathe.
Switching duty and auxiliary contact capacity
At 230 V it carries 3 hp motor load, and at 400 V the auxiliary contacts are rated 3 A — so the same switch block works on both 230 V and 400 V control systems, just with different current limits. Switching rates: 1000 ops/h in AC-1 (resistive loads), 750 ops/h in AC-3 (motor running), but only 250 ops/h in AC-4 (plugging or inching duty). If your application does frequent reversing or jogging, the AC-4 rate is the one that governs thermal rise.
Wiring termination and conductor sizes
The coil terminals are screw-type, so no special crimp tool needed for the magnet coil. Main contact tightening torque is 16 to 8 Nm — the range covers both smaller conductors (lower torque to avoid crushing the wire) and larger ones (higher torque for a gas-tight connection).