Eaton SLD04S5S 400A 7.2kV 125VDC

Note: The inquiry marked 72kV is a typo, the correct rating is 7.2kV, this is the Cutler-Hammer SL series medium voltage vacuum contactor.

The SLD04S5S is a 3-pole vacuum contactor from Eaton Cutler-Hammer SL series, rated continuous current 400A, rated voltage 7.2kV, control coil 125VDC. This SLD04S5S uses vacuum interrupter for arc extinction, designed for frequent switching of medium voltage motors, transformers, capacitor banks and reactor loads. The model suffix S5S defines coil voltage, auxiliary contact arrangement and mechanical latch configuration for this variant.

This SLD04S5S supports high mechanical life for cyclic switching duty, far higher than vacuum circuit breakers. It comes with built-in auxiliary contacts for status feedback and interlock logic. The vacuum bottle structure features low chopping current, suitable for motor starting and capacitor switching applications. It is commonly deployed in Ampgard MV motor control centers, can be matched with separate protection relays for overcurrent, earth fault and thermal protection. The 125VDC coil version is widely used in power plant DC control system cabinets.

The SLD04S5S is widely applied in water pumps, fans, compressors and medium voltage soft starter assemblies in power plants, mining and chemical industries. The classic SL series contactor has been phased out by Eaton. Most available SLD04S5S units are tested surplus spare parts for MCC retrofit and emergency replacement of legacy Cutler-Hammer medium voltage motor control cabinets.