The kW column on a contactor is a summary, not a specification. TeSys gear — like all quality switchgear — is selected in a language of categories and coordination that outlives brand debates.
The selection language
Utilization category first: AC-3 (motors, breaking running current) is the everyday case; AC-4 (jogging, plugging — breaking starting current) derates the same physical contactor hard. A conveyor that inches under operator jog buttons lives in AC-4 whether the catalog page was read or not, and its “oversized” AC-3 contactor welds on schedule. Coordination type with the short-circuit protection: Type 1 (device may need replacement after a short) vs Type 2 (fit to continue) — pick per the downtime cost, and use the manufacturer’s tested combinations tables (breaker + contactor + overload as a set), which is where TeSys documentation genuinely shines.
Overload class matches the start: Class 10 for normal starts, 20/30 for heavy, long accelerations (fans with big inertia, loaded mills) — a Class 10 relay on a 15-second start produces phantom trips that get “fixed” by oversizing, which then protects nothing.
Coil control details that bite: electronic-interface coils (low-consumption, wide-band) for PLC-driven panels, surge suppression as discipline, and voltage sag behavior verified — a contactor dropping out at 70 % dip writes its own restart story.
FAQ
Contactor + overload or an electronic starter (TeSys U/island)? Electronic integrated starters pay where diagnostics and comm integration matter — load current visible in the PLC ends a whole genre of mystery trips.
Mixing brands in one panel? Electrically fine; keep coordination pairs within tested combinations, and the spares shelf singular where possible.
Zone Otomasyon builds and refurbishes MCC panels with coordination tables in the door pocket. Panel engineering.