Eaton Logo

How is the Phase Loss protection determine for the S611 soft starter?

The phase loss protection level is set with the Phase Loss % parameters in the “Protections” mode or modbus register#427; default setting is 80%

The trip delay time is set with the Phase loss trip delay parameter in the “Advanced” menu at P.18 or modbus register#428; default setting = 2sec; protection is disabled if set to “0” sec

The S611 uses current to detect “Phase Loss”, so if the default settings are used the S611 will fault with a phase loss if the current in one of the phases experience an 80% imbalance for 2 sec.

Imbalance = 100* max deviation from ave / ave