Ring Main Testing

[adderzigzag]

Sorry, not another ring main issue i hear you say guidance note 3 and the on-site guide are clear enough. However. I have a collegue who insists on doing the three steps of ring main testing from a socket outlet as its easier to find and get at the ends of the conductors as opposed to raking around in a distribution board. Can anyone have a reason why this cannot be done. I appricate the three steps are to identify polarity and if the socket was then not reconnected properly it wouldnt be good. This would be picked up on an earth fault loop test later. Anyone have a reason why he shouldnt do it at the socket, afterall, you would have to be dumb I know, but you could reconnet with wrong polarity at the dist board.

 

[Mr Mark Sparks]

i do it at the socket if more conveniant and if on a memshield 2 cu so as not to have to fanny about in those deep rcbos

 

[zupos40]

By testing at the socket outlet, how do you ensure compliance with BS7671:2008 Regulation 514.1.2 , 514.8.1.

Also how do you know that the phase is not connected to 2 breakers/ fuses if more than one ring circuit is present

 

[slocm3105]

Always test at the board. Gotta make sure its all top notch in there really dont ya surely matey?

 

[Lou7]

Nothing wrong with testing at sockets. Especially when you have more than one ring, you can't get your legs crossed.

Plus you still check every point on the circuit even the board.

 

[mdavismccoy]

Hi, No I would'nt test at a socket outlet because you need to identify the ends of the ring (in and out). If you test at a socket outlet you still have to identify the ends of the ring in the board and connect them together, to make the loop. It defeats the object of testing at the socket outlet. You will test for resistance at the socket outlets, identifying what is on the ring and which is a spur, which will also identify polarity. Testing at a socket outlet will not identify a cross connection on the neutral or earth bar.

 

[DHES-LTD]

I disagree, nothing wrong whatsoever with doing it at a socket.

 

[securityvillage]

NICEIC are happy for you to test at a socket if the CU is in a difficult area for access. You would check the CU anyway. Why work in cramped conditions

 

[zupos40]

I disagree, nothing wrong whatsoever with doing it at a socket.

It would be great if you would explain further why you think it ok and how you preform the test to ensure compliance with BS7671, are you tooling about initial verification testing or PIR

NICEIC are happy for you to test at a socket if the CU is in a difficult area for access. You would check the CU anyway. Why work in cramped conditions

Can you please state which document you read this in, page number etc. Thanks

 

[securityvillage]

The NICEIC actually do their ring test at the socket in the PIR DVD. It's done by Tony Cable himself. He explains the reasoning behind it as the consumer unit is in an under stairs cupboard which provides difficult ready access.

Page 279 of their PIR Guide

 

[zupos40]

The NICEIC actually do their ring test at the socket in the PIR DVD. It's done by Tony Cable himself. He explains the reasoning behind it as the consumer unit is in an under stairs cupboard which provides difficult ready access.

Page 279 of their PIR Guide

what does he write in the observation and recommendations about access to the consumer unit and what code does he give it.

 

[andyb]

what does he write in the observation and recommendations about access to the consumer unit and what code does he give it.

I imagine he gives it code 4.
A PIR is just a report, it is easier to test ring continuity and r1+r2 from a socket instead of taking the relevant conductors out of a board.
You still need to access the board for other tests, but if it’s easier to test continuity at a socket, why not?
A new installation or circuit is different, you would test the ring continuity before connecting to the board so the question of where you test from does not arise.

 

[zupos40]

I imagine he gives it code 4.
A PIR is just a report, it is easier to test ring continuity and r1+r2 from a socket instead of taking the relevant conductors out of a board.
You still need to access the board for other tests, but if it’s easier to test continuity at a socket, why not?
A new installation or circuit is different, you would test the ring continuity before connecting to the board so the question of where you test from does not arise.

Yes PIR is a report, but I done suffient to know that removing a socket and having to un twist solid 2.5 mm can cause damage and if the person who installed the original installation did not leave sufficient slack it my by hard to reterminate, i inspected socket and wiring were cpc have been twisted together and both conductors placed in 1 piece of sleeving, I personally do all ring circuit testing a ccu and limit my inspection to minimum as I could cause unneccessary damage, if I have inspected the front tested all switches and tested every outlet for ring circrcuit continuity and obtain satisfactory reading I do not distrub, most of my observation are performed at ccu, cooker outlets FCU and ceiling rose, light switches where I have to remove cover to enable me to perform tests.

As well performing the test at the CCU always me to check the phase (now line) and netraul and CPC are in correct sequence, it also enable to check the if there multiple ring that leg have not be installed into more than 1 breaker/fuse, performed in excess of 2000 PIR and found this scenerio about 40 times, also have found radial and ring interconnected.

I now at every CCU / distribution board use a low reading ohm meter switch off all the breakers/ remove the fuses and test on the load side for continuity between each ring/ raidail circuit even lighting (have found lighting and ring interconnected), I know this test is not required but I would recommend doing with you test for ring continuity at CCU or at S/O.

In the case of testing at socket outlet cpc which are both connected to shared busbars and supplementary bonding installed can you trust the result obtained.

I am aware that there are many way of testing I just believing there is less chance of damage the installation testing at CCU.

 

[markythesparky]

testing at a socket outlet is fine for literally collecting circuit readings.

The consumer unit must be inspected to ensure other regulations are met.

 

[andyb]

Yes PIR is a report, but I done suffient to know that removing a socket and having to un twist solid 2.5 mm can cause damage and if the person who installed the original installation did not leave sufficient slack it my by hard to reterminate, i inspected socket and wiring were cpc have been twisted together and both conductors placed in 1 piece of sleeving, I personally do all ring circuit testing a ccu and limit my inspection to minimum as I could cause unneccessary damage, if I have inspected the front tested all switches and tested every outlet for ring circrcuit continuity and obtain satisfactory reading I do not distrub, most of my observation are performed at ccu, cooker outlets FCU and ceiling rose, light switches where I have to remove cover to enable me to perform tests.

No one is telling you you have to test this way, the op was asking if there is any reason that you can't carry out your final ring circuit tests like this and there is no reason.
You have to drop some sockets on each circuit anyway to inspect behind.
If the cables are twisted together and you think there may be a problem then carry out all your tests from the board, or do it from the board anyway. The choice is yours.

The point is, if the board is a mess and the cpc or circuit conductors are not arranged correctly, then write that down as a code 4 and then carry out your other tests from a socket.
It's either that or waste time sorting out the board or not doing the tests.