fake ring

[Safety First]

There is a wiki on this site that covers the means of confirming what appears as a ring, really is a ring-and not a spur

I was thinking about what could present as a lookalike- all I can think of is a spur that is spurred off again?

The reason I ask is that I have a double socket recently installed by Elec'

I looked behind and was pleased to see double of all going to terminals. Testing using mentioned wiki is fine, but I had expected the Elec. to have taken a spur rather than putting a ring in- the former being easier for him?!...

Unless he spurred off a spur? But he would not have done that ?
Nb. Am not suggesting he's dodgy- just speaking my thoughts, for interest. Nothing will take the place of full process/testing...Amen

 

[phatboy]

He may have removed a cable from an adjacent socket, suitably joined that cable to the new cable and run it to the new socket location, and run a new cable between the 2 sockets. This would make it part of the ring.

This would be fairly easy if it was an upstairs room and the cables went into the loft space.

Or the existing socket could have been at the end of a radial circuit.

 

[ricicle]

Why did you feel the need to check behind the socket in the first place - did you not trust him ?

 

[Safety First]

Why did you feel the need to check behind the socket in the first place - did you not trust him ?

Sorry- missed your Q.

A.No it was nothing to do with trusting him, I was following guidance; the How to (connect a new socket) on this site tells you to start at possible socket to spur from by checking whether you have one set (a spur) two sets (a ring) or three sets of wires (a ring that has been spurred off already).


Lastly, I cannot find the guide to how you double check that the ring is a ring. Something about testing continuity on all L, E, and N?

B*ggered (do I mean electrocuted?) if I am going to try anything without the guide but I cannot find it? Can anyone help please?[/u]

 

[EFLImpudence]

http://www.tlc-direct.co.uk/Book/8.4.2.htm

 

[Safety First]

http://www.tlc-direct.co.uk/Book/8.4.2.htm

Thanks. Somewhat baffled by that lot- testing at the consumer unit seems a little too far.

Also, the stickers that look to have come with the new Consumer Unit are wrong. The 'Downstairs sockets' sticker is pointing to the MCB for the upstairs sockets....

I am sure I can remember someone writing about a test to check you have a ring, by checking at the socket for continuity of the L, E, N. Thinking about it, they wrote that you need to ensure that all the sockets for that ring were switched off....??

I (think) I understand that if the socket I just tested showed no continuity then it would indicate a spur off a spur- given that there were two sets of wires going into it.

Like I said, it was not about trusting the sparky that recently installed the socket, but trusting what I see according to the test process (that I cannot find). Will keep looking.

 

[Safety First]

Why did you feel the need to check behind the socket in the first place - did you not trust him ?

Oops, sorry. Just realised your point. I failed to mention that I was working out the options for joining a FCU to (hopefully ring) socket and from FCU to outside socket.

Yes indeed- why do I go about checking behind sockets that Sparky has just fitted!

 

[ericmark]

If the spark was a good one and can be trusted he will have completed either a minor works certificate or an insulation certificate most likely minor works.

On minor works it states appropriate inspection and testing, however should always be carried out irrespective of the extent of the work so there should also be a schedule of test results. Under this there are (R1 + R2) or R2 plus ring if it is a ring then ring should be ticked and (R1 + R2) will have a value.

If you have the paperwork since only two cables then likely it is a ring. If there is no paperwork then you do need to worry as when electricians break the rules it is common that they will also often fail to leave a paper trail showing they did it wrong. Human nature.

I have one in my mothers house a bell transformer was changed to a socket and a DC power supply plugged into the socket. No label on the socket saying only for bell transformer and plugging in the RCD tester the RCD fails to trip likely because there is no RCD fitted. Repeated calls asking for paperwork always told they will sort it and send it to my mother but never arrives. Since they were not employed direct buy though council one would expect everything to be A1 but clearly not.

So in the main if paperwork exists likely all OK. Paperwork missing likely something wrong.

To test a ring does require something to bell out the circuit. It could be a battery door bell and the two wires which normally go to door push hence called belling out but normally for DIY it's a buzzer built into a multi-meter. Electricians should use special meters so instructions for electricians will be different to what a DIY will do.

So step one is switch off the main isolator not just the MCB all power off at main isolator.

Remove socket and then in turn remove each pair of wires and put meter between them and in spite of them not touching they should still show they are connected together. This is done with each pair. Then returned to socket and the socket screwed to wall before power is put back to circuit.

There are other tests you should do at the same time making sure no connection between line and earth plus neutral and same with neutral should be no connection to either line or earth.

This is not an exhaustive test and electricians would do more but if I go into them all likely you will get confused so leaving it at that.

 

[Safety First]

If the spark was a good one and can be trusted he will have completed either a minor works certificate or an insulation certificate most likely minor works.

On minor works it states appropriate inspection and testing, however should always be carried out irrespective of the extent of the work so there should also be a schedule of test results. Under this there are (R1 + R2) or R2 plus ring if it is a ring then ring should be ticked and (R1 + R2) will have a value.

If you have the paperwork since only two cables then likely it is a ring. If there is no paperwork then you do need to worry as when electricians break the rules it is common that they will also often fail to leave a paper trail showing they did it wrong. Human nature.

I have one in my mothers house a bell transformer was changed to a socket and a DC power supply plugged into the socket. No label on the socket saying only for bell transformer and plugging in the RCD tester the RCD fails to trip likely because there is no RCD fitted. Repeated calls asking for paperwork always told they will sort it and send it to my mother but never arrives. Since they were not employed direct buy though council one would expect everything to be A1 but clearly not.

So in the main if paperwork exists likely all OK. Paperwork missing likely something wrong.

To test a ring does require something to bell out the circuit. It could be a battery door bell and the two wires which normally go to door push hence called belling out but normally for DIY it's a buzzer built into a multi-meter. Electricians should use special meters so instructions for electricians will be different to what a DIY will do.

So step one is switch off the main isolator not just the MCB all power off at main isolator.

Remove socket and then in turn remove each pair of wires and put meter between them and in spite of them not touching they should still show they are connected together. This is done with each pair. Then returned to socket and the socket screwed to wall before power is put back to circuit.

There are other tests you should do at the same time making sure no connection between line and earth plus neutral and same with neutral should be no connection to either line or earth.

This is not an exhaustive test and electricians would do more but if I go into them all likely you will get confused so leaving it at that.

Thanks Ericmark, I re-read until the penny dropped on that belling business.... you have been in this for some time then!

I will hunt for papers,we have filing systems for this!!!!

I did test continuity by

Checked current to socket.
Turned off Mcb to 'ring'.
Checked current off.
Repeated
Removed socket plate. Showed 2sets wired in there. Tested every wire for current with v meter.
Then separated all the wires out and checked continuity-belling.

L-L CONT
L-E chirping cont.
L-N CONT
E-E CONT
E-N chirping cont.

When I say chirping I mean instead of clean continuous continuity tone, it sort of vibrates.
It was after everything was back on the wall that I remembered the part about turning off all the sockets suspected of being on the tested ring. Did not remember to do this though

 

[ericmark]

It is pointless to quote whole post when quoting just select bits as below.

Then separated all the wires out and checked continuity-belling.

L-L CONT

This is good shows L-L is in a ring

L-E chirping cont.
L-N CONT

Means you left something plugged in when testing it will also account for chirping plus it means the L-L reading could be incorrect as equipment left plugged in could be messing up the readings.

E-E CONT

This is good shows E-E is ring

E-N chirping cont.

The E-N chirping shows E-E has not been compromised by leaving items plugged in but there is no N-N reading which also should be made.

So in real terms the results from your tests are.
It is suppose to be a ring and likely is so you can take a spur from this point. However the tests as documented do not show the ring is healthy not enough tests and not enough care to unplug all items. Using the ohm reading rather than buzzing you can get around the odd item left plugged in.

We look for L-L, N-N, E-E readings of less than 2 ohms but to get accurate readings that low needs a special ohm meter which uses at least 200ma for the test this can't really be done with a multi-meter.

There are other tests we make again with expensive test gear like insulation this uses 500 volt for the test. Plus also a RCD tester able to measure the time in milliseconds to trip (allowed 40ms) and loop impedance testers which are used to test the earth has a really good connection. These meters cost too much for the DIY guy but there are some plug in units which although not as good will give a good indication should things not be as they should be. A tester like this

costs around £50 and will find many faults. If DIY electrics are on going well worth while but at £50 likely cheaper to get an electrician to test than buy one of these just to do one socket. Please note the one shown has a loop test. There are some very cheap testers without the loop test but it is the loop test that shows you have a good earth so I think worth the extra.