Earth Fault Indicator (EFI)

The picture shown tells how this device works.

Earth Fault Indicator (EFI) is a part of a distribution network that is provided for each of the incoming cables in a ring circuit to indicate the faulty section during earth fault.

EFI is composed of an earth fault relay and indicator which is directly operated by a secondary current from the split-core type core-balance transformer. The indicator is automatically re-set by single phase 230V supply.

Commissioning of 150MVA, 132/11kV DLFF Substation

I had the privilege to be part of the commissioning team for one of the substations of Dubai Electricity and Water Authority (DEWA), namely Dubai Logistics Freight Forwarders or DLFF 132/11kV, 3x50MVA Substation. This means that now, the electrical energy for the whole city of Dubai has again increased.

The team composed of the Commissioning Engineer, Protection Engineer, Transmission Operator, SIEMENS contractor, and yours truly from the Distribution System Operation.

The scope included commissioning of gas-insulated switchgear (GIS) by SIEMENS; 2×132kV line feeder; 3×50MVA inter-distribution transformer feeder; and a double busbar including bus-section disconnectors and earthing switches; automation system is used for control and monitoring. The man-machine interface is the BAILEY SCADA by ABB.