Sigma D++ Short circuit indicator 200-2000A

The Sigma D++ is a combined directional short-circuit and directional earth fault indicator for medium voltage distribution networks.

The devices are current sensor powered. The voltage information will be taken from an integrated voltage detecting system (Wega series), from an HR interface or capacitive post insulators.

The Sigma D++ provides additional earth fault detection methods for compensated and isolated neutral networks.

For the transient earth fault method only three single-phase current sensors are needed, but auxiliary supply is mandatory. The connection of a summation current sensor is optional.

For all other methods no auxiliary supply is needed, if the load current is >5 A.