ENLZ

ENLZ devices are used for localization of short circuits and single line-to-ground faults in underground cable networks, providing short-circuit sensor data and synchrophasor measurements of zero-sequence currents and voltages to a data processing center. 

The algorithm for the localization of faults is based on the analysis of the amplitudes and phases of the zero-sequence current and voltage phasors, measured at section boundaries of the distribution network.

Equipped with six optical inputs for short-circuit sensors, and two analog inputs, one ENLZ provides monitoring data for two cable lines. 

To measure 3I0 and 3U0, ENLZ connects to zero-sequence current transformer, and instrument voltage transformer with 3U0 winding through a VMT step-down voltage transformer.

ENLZ uses ENCM-3 remote terminal unit for time synchronization from GPS/GLONASS. ENCM-3 transmits data from ENLZ to a data processing center via Ethernet or cellular network (3G/2G).