Answer / arnab

sensitivity of earth leakage relay is more than earth fault
relay. earth leakage relay is connected with core balance
current transformer.

Answer / rajdip thakur

Earth fault relay trips when the current through the neutral exceeds a preset value.Simply it acts on the superposition theorem. Whether the vector sum of the phase current and the neutral current are same or not.If not then it operates.
But the earth leakage circuit breaker operates when some current flows from neutral to ground. We know that the voltage difference between neutral and ground is zero.It operates only when there appears some voltage.

Answer / tina john

Eath fault implies a significant contact between phase and ground and it can cause heavy current and can cause damage; earth leakage is a high resistance contact with earth that the phase may have in cables; devices etc.; since the current is small it wont create any problem usually. However, its a sort of indication that there are insulation problems present in the cable/devices.

https://automationforum.in/t/what-is-difference-between-elr-and-efr/173

Answer / govarthinam

Hi radhika

Where u find the Earth leakage relay and Earth fault
relay?pl specify the application.

Regards
Gova

Answer / gunasekaran

earth leakage relay are sensitive earth fault relay. both
are working same principle residual current method.first
one is we r using CBCT second one is ordinary CT.

Answer / mrt

both the relay are same, both relay are operated through
the core balanced circuit breaker. normally the cbct
contains the current(say nuetral current ) is zero. at
balanced condition the neutral current is zero. in case any
fault(insulation,ground fault..) in the line the neutral
current will change from zero. this will operated the relay

Answer / ramniveth

both are same

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