Sensitive Earth Fault Relay Connection

Sensitive earth fault is given by providing a core balance CT CBCT to the feeder cable.

Sensitive earth fault relay connection. Ad Early detection of ground faults on ungrounded systems allows critical systems. However systems such as signalling circuits whose correct function is essential to safety should have any sensitivity to harmonic interference designed out of them at the outset. In this video the philosophy behind the restricted Earth Fault Protection has been elaborated.

We provide this protection additionally to normal Overcurrent and Earthfault relays. The Restricted Earth Fault Relay is connected in this closed path. These types of devices protect electrical systems and components from damage when an unwanted event occurs such as an electrical fault.

Restricted Earth Fault Protection is also known as differentia. Restricted earth fault protection Restricted earth fault REF protection is a sensitive way to protect a zone between two measuring points against earth faults. Earth fault relay senses these faults.

In our electric utility we have been using Sensitive Earth Fault SEF relays for the protection of the 11 kV overhead distribution lines and they are set for operation at 6 Amps and 5 seconds time delay. Two CTs are required for the entire frequency range or. Up to twelve channels scanned in parallel interconnect additional devices to add more.

The relay is designed for sensing the fault current which is 15. The ground fault detection sensitivity. The sensitive earth-fault relay is suited for both primary and back-up earth-fault protec-tion.

A digital relay can reliably measure currents in the range of a few milliamperes. By using 28 x 08 mm tabs a bridge connection. Scheme consists out of a ring CT Core Balance CT around the three phase.