Earth Leakage relays

Hello Ritesh,

It appears that you have entered your entire Homework assignments in these several almost simultaneous questions.

You could also research your subjects via Internet Search Engines.

The reason I say that, is that your questions are ones not well formulated, and look as if your teacher has given you several questions as a Homework assignment.

If you just Copy/Paste answers from here, you are never going to actually remember them, when you are going to need those answers most...in an examination, or later in a Professional situation.

If you do a bit of effort, and actually research the answers (remember to formulate the questions in a more complete way), you are likely to retain the information for life.

If this is not so, please advise here, formulate your questions so they can actually be answered, and I'm sure you should be helped......

Extremely well put!

I would only add that anyone contemplating taking ELCBs out of circuit is either trying to kill himself or someone else, which means that I do not assist in answering such questions......

This depends on the application and the kind of function you need.

For instance, for isolated systems, a relay as you have described as "leakage relay" is not much as an overvoltage protection to detect an earth fault by means of connecting it in the open delta of voltage transformers.

If the application concerns a generator, you may protect it from phase to ground faults by means of stator ground faults protections.

For further information I suggest that you read about this by consulting some relay manufacturers such as ABB, GE. SCHWEITZER and SIEMENS. You may get the addresses through Google.

Regards