Ze and PFC test questions. Please Help.

[nazoom]

Hi

I am trying to carry out Ze test on a single phase system, TN-S. I am unsure where in the main switch the line leads contact is it at the incoming (supply)points or the feed point at the main switch or does it not matter?

Also is it the same for PFC?

Many thanks

 

[telectrix]

i always take readings off the top ( incoming ) side of main switch with the switch OFF.

 

[Guest112]

agreed main switch off and remove earthing conductor perform Ze to get a true reading. RECONNECT IMMIEDIATELY DO NOT FORGET and test pefc and pscc depending on what meter your using etc

 

[nazoom]

Thanks for the quick reply.

 

[Guest112]

no prob any more details wanted mate?

 

[nazoom]

Many thanks for your help mate.

One more question; when carrying out RCD test for shower circuit in single phase TN-S system, where does the line and neutral leads make contact with? Do they contact on the top (incoming form the main switch) or bottom (busbar) of RCD? I know it is a live test.

Thanks again.

 

[telectrix]

you are testing the RCD so leads must be connected to the load side.

 

[jase]

you must isolate the board as you need to take the incoming earth out to avoid parallel paths, with the main switch off you would only have power at the incoming side

 

[nazoom]

Thanks guys.

 

[Guest112]

tele beat me again load side of the rcd, some may argue that you shouldnt open/work in a live db especially to do live testing but i live in the real world so load side of the rcd or at a point on the circuit being tested

 

[nazoom]

So its the lower contacts on the rcd?

 

[wallyanker]

I would test at shower terminals. If testing at the RCD, test on load side.

 

[nazoom]

Thats solved.

Many thanks to all.

 

[Lucas123]

yeah i would opt for shower isolator/pull cord first if easily accessable