Short circuit testing of switchgear

[igel]

Hi guys,

What is making angle in switchgear testing & why it is important.. At what angle switchgears has to be tested?

 

[ScottyUK]

In a three phase breaker the contacts will make at pretty much the same moment in time, so there will be differences in the voltage across the closing contact at that moment. In an inductive circuit there will be a DC transient component imposed on the AC current which flows immediately after closure, with the potential to reach a value much larger than the normal peak of the AC waveform and imposing large magnetic forces on busbars and insulators.

Test conditions are clearly defined in the standards to which you are testing - there isn't a single answer to that part of your question.