Polarity test ( help )

[L Plate]

Good day all,

From my previous thread , the lighting circuit , radial circuit and the switch fuse to CU ..

http://www.talk.electricianforum.co.uk/showthread.php?t=9776

With all your help regarding dead testing , It really give me the very clear idea on how to do the Continuity test and Insulation resistance test , Please can anyone help me how to do the Polarity test for

a) lighting circuit

B) power circuit

c) SWA circuit

I have read the OSG page 75 / 9.3.1 ( testing checklist ) 612.2 but it does not clear to me

I think ( not so sure ) some method in continuity will be the reading for polarity ?? not really sure about this ..please can anyone give me a clear idea

BTW in college we are using FLUKE 1652 TESTER

thanks again

Good day to all

 

[Manator]

Polarity is confirmed by doing your continuity checks. As you go through the testing by whichever method you use ie wander lead or temp connections on radials and the set procedures for testing continuity of rings.

If any connections are reversed you will find that there is a crossover of continuity from say the line and nuetral or any combination that is found.

All end to end on a circuit will almost be identical except for the earth which is of a smaller csa.

 

[L Plate]

Polarity is confirmed by doing your continuity checks. As you go through the testing by whichever method you use ie wander lead or temp connections on radials and the set procedures for testing continuity of rings.If any connections are reversed you will find that there is a crossover of continuity from say the line and nuetral or any combination that is found.

All end to end on a circuit will almost be identical except for the earth which is of a smaller csa.

Thank you Sir for your info , so this means that as long as I have cleared and confirmed my continuity reading , it means the Polarity test is also cleared?

thanks again

 

[Brian 157]

If you do your CPC continuity testing by method 1 (R1+R2) and your readings go open circuit (over range) when you open the switches then you have proved polarity. If you use method 2 (long lead or R2 only) or your assessors require it a separate polarity test is required, this is "long lead" method (ie end to end) on the line conductor. If you have closed circuit with switch(es) closed and open circuit with them open then polarity is confirmed. For a ring circuit step 3 of ring testing (OSG P82) also confirms polarity.

 

[m4tty]

I would definitely recommend a copy of GN3 as its probably my most read book and really does help with the testing side of things. Cheers

 

[sparkytim]

Hi L Plate

On all RADIAL circuits you can use the same method, either the WANDER lead method which will give you R2 or the R1+R2 method.

For WANDER LEAD you will require a long conductor to reach from the Consumer Unit to the last point on the circuit , Light, Socket, Shower or what ever is on that RADIAL circuit.

You connect one end of this conductor (I use a reel of 4mm earth wire) to the CPC of the circuit under test at the Consumer unit using a connector block, and unreel it all the way to the end fitting. Then you connect one lead from your Meter to the end of your reel and the other to the CPC at that fitting. You must DEDUCT the resistence value of the reel of cabel that you have used and this will leave you with the R2 value of your circuit.

Most of us probably use the OTHER method

We connect the CPC and L conductors together using a connector block at the Consumer Unit and then measure the R1 +R2 value at ALL fittings until you find the highest reading.

Dont forget to ZERO your leads first, just connect together the two croc clips (Flat side to Flat side NOT the moving sprung side) and push the ZERO button on your meter, then all readings you take will deduct the resistence value of the leads.

This will also provide a POLARITY check that the L is Not N as well as the continuity of the CPC. IT WILL not PROVE if the CPC and Live are reversed as pointed out in yesterdays thread.

 

[L Plate]

I would definitely recommend a copy of GN3 as its probably my most read book and really does help with the testing side of things. Cheers

Matt,

cheers again .. GN3 ?? where can i buy it mat? is the book says GN3 ??

 

[L Plate]

Hi L PlateOn all RADIAL circuits you can use the same method, either the WANDER lead method which will give you R2 or the R1+R2 method.

For WANDER LEAD you will require a long conductor to reach from the Consumer Unit to the last point on the circuit , Light, Socket, Shower or what ever is on that RADIAL circuit.

You connect one end of this conductor (I use a reel of 4mm earth wire) to the CPC of the circuit under test at the Consumer unit using a connector block, and unreel it all the way to the end fitting. Then you connect one lead from your Meter to the end of your reel and the other to the CPC at that fitting. You must DEDUCT the resistence value of the reel of cabel that you have used and this will leave you with the R2 value of your circuit.

Most of us probably use the OTHER method

We connect the CPC and L conductors together using a connector block at the Consumer Unit and then measure the R1 +R2 value at ALL fittings until you find the highest reading.

Dont forget to ZERO your leads first, just connect together the two croc clips (Flat side to Flat side NOT the moving sprung side) and push the ZERO button on your meter, then all readings you take will deduct the resistence value of the leads.

This will also provide a POLARITY check that the L is Not N as well as the continuity of the CPC. IT WILL not PROVE if the CPC and Live are reversed as pointed out in yesterdays thread.

thank you for the info and thanks all for your help ...

 

[Apache]

Matt, cheers again .. GN3 ?? where can i buy it mat? is the book says GN3 ??

bookshops

http://astore.amazon.co.uk/talkelectrici-21

 

[ianmacd]

bookshops http://astore.amazon.co.uk/talkelectrici-21

GN3 i.e. Guidance Note 3