Earth Fault Relay vs. Earth Leakage Relay

I think this pretty much sums up the question, where leakage is a small amount and fault current is the whole supply in a fashion.

a leakage could result in a earth fault current, but I think not the other way around.

but generally, both are also a current that is taking a "different" path from the supply back to ground.

Appreciate your reply Abbas and Snaketails.

My other question. Is there any guideline or codes recommending the usage of ELR / EFR and in any particular situation? I have seen a consultant putting ELR for 800A outgoing MCCB and another recommending EFR and hence the confusion.

I think first you must give your requirements to the consultant then ask him yo give you choices.

In my opinion both EFR and ELR should be selected rather go for common relay which can provide you both.

There are many relays/controllers in the market which can offer more versatility.We are using GE F650 relay, covering all the safeties of currents, voltage, frequencies and monitoring of breaker status etc..

I am not aware of separate RCDs for earth fault and earth leakage. Of course, RCD sensitivity will be customer-adjustable in majority of the cases. In this context leakage and fault are the same phenomenon.

So are "Earth Fault Relay" & "Earth Leakage Relay" two different devices and function or are they actually referring to the same thing? How about the PCT (current transformer) for the relays?

No, there isn't.