2391 exam question

[trebor]

Main reason for this is that you can tell how good the earth is upstream, and whether or not the install is relying on the downstream earth, as if it was it would be a failure

Not correct, there is only one earth source and that is at origin, all others are parallel earth paths, Ze is measured with earthing conductor disconnected so as to measure external only, otherwise it is not Ze

 

[Goody]

The owner has agreed that the whole installation may be isolated in order for tested to be carried out.There is a period of 1 hour allocated for this work.List the test that MUST be carried out during this period(individual circuits may be isolated after this period)

Ze and all "dead tests"; I guess!

 

[martinxxxxxx]

If it's not a PIR, then it's an 'Initial Verification' and wouldn't be energised until the testing had been done anyway - so you wouldn't need the 'one hour' shutdown.

If the owner is allowing you one hour to shut the thing down, then it must be an existing installation, so PIR.

The only time the tests are required to be done in the stated order are during 'initial verification'.

Would this also apply to an addition or an alteration to a circuit that had been isolated at the C/U, but required an EIC to be completed?
Then the order of test would be as per section 1.2 of GN3 as there still needs to be @Initial verification' following this work too?

I am sitting this exam soon, so I just am exploring the subject and not trying to be funny in anyway

Martin