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Does it matter which method (method 1 or method 2) you use when testing for continuity of the circuit protective conductors? Or is each method dependent upon which the type of circuit you are testing on ring or radial?

I have been told that test method 1 is used for lighting and radial circuits and that test method 2 is used for ring final circuits. However this seems to contradict what I've read elsewhere.

Please can you clear this up for me thanks.
 
For radial circuits Method 2 involves using a wander lead attached to earth terminal at the DB and can confirm cpc continuity and impedance. Method 1 can test for continuity and impedance of both the protective and line conductors if that is required.
 
Read your GN3 for a full explanation. Either method can be used to check continuity of the protective conductors. That is all that you get with Method 2.
If you use Method 1 then you also get the R1+R2 measurement and the ability to check polarity (in a lighting circuit, for instance).
 
For radial circuits Method 2 involves using a wander lead attached to earth terminal at the DB and can confirm cpc continuity and impedance. Method 1 can test for continuity and impedance of both the protective and line conductors if that is required.

Why would you use test method 2 for radial circuit and not test method 1? Do you know of any links that can explain why this is ? Thanks
 
You really need to read Guidance Note 3. Its necessary reading for Inspection and Testing.

In general, for new circuits you would always do method 1. It will save you time as I said above as it will tick the polarity box and you'll need the R1+R2 figure for the cert and to determine your expected Zs!
I only use method 2 when carrying out an EICR. Its easier so you do not have to take existing decorative light fittings apart and especially if you have light fittings at a substantial height, I then use a pole + wander lead.

For an EICR it is possible to carry out a method 2 test without having to disconnect power from the installation. Carrying out method 1 requires you to connect the line conductor of the circuit under test to earth, not something I would entertain doing while the main switch is still ON!

There's a number of threads on this. eg https://www.diynot.com/diy/threads/r2-tests.209790/
 
You really need to read Guidance Note 3. Its necessary reading for Inspection and Testing.

In general, for new circuits you would always do method 1. It will save you time as I said above as it will tick the polarity box and you'll need the R1+R2 figure for the cert and to determine your expected Zs!
I only use method 2 when carrying out an EICR. Its easier so you do not have to take existing decorative light fittings apart and especially if you have light fittings at a substantial height, I then use a pole + wander lead.

For an EICR it is possible to carry out a method 2 test without having to disconnect power from the installation. Carrying out method 1 requires you to connect the line conductor of the circuit under test to earth, not something I would entertain doing while the main switch is still ON!

There's a number of threads on this. eg https://www.diynot.com/diy/threads/r2-tests.209790/

Thank you for your reply I have read guidance note 3 along with a few other inspection and testing manuals for various manufacturers. I have read and understand that the purpose of testing for cpc continuity is to verify that the cpc forms a continuous path around the circuit under test.

I have also read that testing for continuity of ring final circuit conductors is done to verify that the line, neutral and protective conductors form a continuous path around the circuit.

What I am asking is why is it necessary to conduct a cpc continuity test on a ring final circuit if the test for continuity of ring final circuit conductors, checks cpc continuity anyway?

Thanks.
 
What I am asking is why is it necessary to conduct a cpc continuity test on a ring final circuit if the test for continuity of ring final circuit conductors, checks cpc continuity anyway?

The way you have worded the above causes me confusion
Are you asking
Why do you use the method 2 test when you have already measured cpc continuity of the ring ?
 
What I am asking is why is it necessary to conduct a cpc continuity test on a ring final circuit if the test for continuity of ring final circuit conductors, checks cpc continuity anyway?

The way you have worded the above causes me confusion
Are you asking
Why do you use the method 2 test when you have already measured cpc continuity of the ring ?

Sorry for confusion. What I'm asking is do you need to carry out a CPC continuity test on a ring final circuit when the test for continuity of ring final circuit conductors tests the continuity of the CPC?

Are CPC continuity tests just for radial circuits ?
 
What I am asking is why is it necessary to conduct a cpc continuity test on a ring final circuit if the test for continuity of ring final circuit conductors, checks cpc continuity anyway?

Thanks.
Hi - as you say, with a new rfc the "3 step continuity test" of GN3 will test continuity of all conductors. Polarity and presence at all outlets is also confirmed.
 
Sorry for confusion. What I'm asking is do you need to carry out a CPC continuity test on a ring final circuit when the test for continuity of ring final circuit conductors tests the continuity of the CPC?

Are CPC continuity tests just for radial circuits ?
When testing a new circuit (remember the sequence of testing) it is necessary to tets the continuity of each conductor before carrying out the next test.
It is pointless carrying out an insulation resistance test on a circuit unless you have foirst determined that the circuit does not have a big gap in one or all of its conductors.

Given this basic requirement, method 1 is the way to go to determine r1, r2 and rn. Only by this method can you see if the values of r1, r2 and rn seem correct (ie r1 equal to rn and r2 proportionally higher than r1). You don't move on to any further testing until this basic data has been gathered and validated. This is needed for all circuits - ring and radial.

Method 2 only proves the continuity of the protective conductor which is not enough for anything but an EICR.
 
When testing a new circuit (remember the sequence of testing) it is necessary to tets the continuity of each conductor before carrying out the next test.
It is pointless carrying out an insulation resistance test on a circuit unless you have foirst determined that the circuit does not have a big gap in one or all of its conductors.

Given this basic requirement, method 1 is the way to go to determine r1, r2 and rn. Only by this method can you see if the values of r1, r2 and rn seem correct (ie r1 equal to rn and r2 proportionally higher than r1). You don't move on to any further testing until this basic data has been gathered and validated. This is needed for all circuits - ring and radial.

Method 2 only proves the continuity of the protective conductor which is not enough for anything but an EICR.
Not trying to confuse the issue TTC but r1 r2 and rn are for ring finals only, aren't they? I could be misunderstanding your last post, no pun intended
 
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