INSULATION TESTING ON 3 PHASE BOARD

[speedster]

Hi All. I was wondering how others do insulation testing on a 3 phase board,in particular,Neutral to Earth and Phase and Neutral combined to Earth.The problem of course is that on a TN-C-S the Neutral and Earth are combined at the intake position.If there is a 4 pole isolator,the neutral can be isolated,so no problem but most isolators are 3 pole.I did one the other day and disconnected the Neutral inside the board,But I'd like to know how others do these tests.

Thanks,

Speedster.

 

[Zeespark]

Turn the board off at the main switch, unplug everything, then clip your clips on L-N, L-E, N-E, switch on circuits individually without the need to disconnect cables.

Andy

 

[ADS]

Hi mate,

There should be a test link on the neutral bar, inside the board - disconnect it (after safe isolation)

I'd disconnect it carefully, then re-test N-E with your voltage tester (the 11th test for safe isolation)

After that, do your normal 10 point IR test or, if you need to test Line/Neutral connected together to earth, croc clip the busbars and neutral.

MCBs closed, either way - and don't forget to re-instate the test link

 

[kme]

Same way I do it.

 

[speedster]

Thanks a lot guys.

Best wishes Speedster.