Ring final test from socket???

[Boatelec]

I'll probably receive cries of abuse that this query was dealt with years ago but not when I was in the forum so........When testing ring can anybody think of a reason why the ring final tests (R1,R2 and Rn + link test) shouldn't be done from the back of a socket or other outlet on the ring. As you'll all be aware it's sometimes bloody difficult to work in CCU in back of a cupboard and in particular to identify correct cables for the link test. It would be much easier from back of socket etc.

 

[ackbarthestar]

You could save yourself a little confusion, by checking the number of conductors entering the fuse holder/mcb at the origin before making the test at the socket.

However, one small disadvantage is likely to be the inability to identify the circuit at the ccu and order of circuit conductors

 

[richy3333]

GN3
continuity of ring final circuit conductors are undertaken at the DU or CU.
Also see 612.2.2

Also how would you know the PD is suitable for the type of wiring etc?

 

[Amp David]

Its deemed ok to test at the socket on and EICR.

Only thing with testing at socket is you can't isolate circuit N and CPC from others if needed on your ins res tests.

 

[Farmelectrics]

you would get false readings on your cpcs as they are terminated in earth bar so paralell earths would come in to play

 

[Farmelectrics]

amp dave were have you read its deemed to be ok from

 

[dagrat]

agree with Amp David, it is sometimes a lot easier (and safer) to conduct the test at a fitting, particularly if access and lighting are an issue.

 

[Amp David]

amp dave were have you read its deemed to be ok from

LOL, I hate to say this and do not 100% agree but it was from the NIC, its on their guide to PIRs

 

[tony mc]

When conducting PIR's your going to come across CU 's which are crammed full and a total mess!

So what do you do re the testing of RFC!

IMO trying to locate the ends of the CPC's and neutrals can introduce faults in the board and can cause you grief so I carry out the tests at suitable socket outlets knowing that the results will include parallel paths and the neutral is still connected so IR tests are affected!

I would like to carry out these tests at the CU but sometimes this is just not possible.

When filling in the EICR the above can easily be documented along with all of your other observations and recommendations about the premises especially Item 4.1 on the schedule.

I am sure others will have very different veiws on the subjest!

 

[Silly Sausage]

tony mc, I agree.

re 612.2.2, doesn't specify where the test should be done.

I think it's a good case for marking all the conductors in DBs with circuit identification...Amd 2???

 

[Silly Sausage]

Here's an example, singles in trunking...

Neutrals appear to be in correct order, but would you trust that they are?
I wouldn't, bearing in mind that the place was in use, so powering down circuits willy nilly, or disconnecting neutrals on a live circuit, wasn't an option. Customer would go mental!

 

[ashrow]

off topic !, when i do installs with singles i always label all cores inside the DB ie on the phases, phase colour and circuit number, neutrals and CPC circuit number

 

[Boatelec]

Thanks for helpful replies Guys and Gals. I am not confused and I always identify the conductors where they leave the fuse carrier/breaker. The problem is seeing which conductor goes into which sheath further back and often behind the CCU. As you'll all be aware it's much easier to see both sheaths behind (most) sockets and there's more room. Electrically I can't see any reason why not. A ring being just that; it doesn't seem to matter where you test it. Or am does anyone know different.

 

[trev]

The false IR readings is the only thing I can think of, you could whip the cover off the CU anyway to check the PDs but if you have it open you may as well test from there as there's always choc block to extend the cables temporarily to a useable length

 

[Adam]

In larger DB's, and singles in trunking, I almost always carry out ring final tests at an outlet. The readings will be no different, and it is generally much easier to disconnect and test at an outlet than some DB's.

With regards to parallel paths, you will also get them at the DB if they exist. Take a trunking / conduit system, all sockets will be linked by their CPU and the metal work.