One socket down on ring - test identification

[HSwizza]

Hey all,
Training to be an electrician and trying to get my head around testing.

If a socket was to have no voltage but all other sockets on the ring work, what example reading would I get to show it is in fact a fault on the ring?

Would it be as simple as when I do my ‘little rs’ the tester would show no continuity?
I.e 99.9 (refer to this for last paragraph)

The thing that would confuse me is how the socket would not get a supply from either side of the ‘leg’? ( my understating is typically if one leg goes down the other leg still works and energises said socket)

I guess to summarise this question. What sort of result would indicate it is a fault on the ring even though all other sockets work?

Thanks for your time, I still get bantered on site so fully expect some here which is fine but if you could guide me that would be more than fantastic.
Just trying to apply myself.

 

[Pete999]

Hey all,
Training to be an electrician and trying to get my head around testing.

If a socket was to have no voltage but all other sockets on the ring work, what example reading would I get to show it is in fact a fault on the ring?

Would it be as simple as when I do my ‘little rs’ the tester would show no continuity?
I.e 99.9 (refer to this for last paragraph)

The thing that would confuse me is how the socket would not get a supply from either side of the ‘leg’? ( my understating is typically if one leg goes down the other leg still works and energises said socket)

I guess to summarise this question. What sort of result would indicate it is a fault on the ring even though all other sockets work?

Thanks for your time, I still get bantered on site so fully expect some here which is fine but if you could guide me that would be more than fantastic.
Just trying to apply myself.

Try You-tube there are many easy to follow RFC testing videos available for learning purposes.

 

[static zap]

Do you think the ring may still be intact .. But is the socket faulty ?
(If its switched .. feel action)

 

[telectrix]

this is where RFC testing becomes more complex. as you say, 1 leg could be down on any of the 3 conductors but all sockets would work. your first test would be end-end - r1, rN, r2. this would establish whether ir not a conductor was not continuous. if there is a break on any conductor, a wander lead and a meter measuring resistance, would track down the break.

 

[SparkyChick]

By definition if an accessory on a ring is without power, it is a fault on the ring.

The key here is not to assume anything... if one socket is without power then you may or may not get values for the little r's. It's entirely possible that the conductors are twisted together (thus maintaining the end to end continuity) but are just poorly terminated and have thus pulled out of the socket or aren't making a good enough connection resulting in a serious voltage drop at the affected socket when placed under load. Of course the switch could also be bad, or the internal components of the socket could have failed.

If only one socket is without power on a ring I would start there... I probably wouldn't do end to end checks until after I'd investigated the one place without power. If multiple places are without power then you have to narrow it down a little and end to end checks are a good place to start because then you'll know whether which conductor you're looking at for bad connections... it won't tell you how many bad connections but it's a step in the right direction as you'll learn a bit more about the fault.

There are a lot of possibilities... but if the end to ends are good, then you have to look at what's connected. If they aren't, you still need to look at what's connected and there are ways of getting a handle on where the problem may be by creating a map of the circuit so to speak and carrying out specific measurements at each accessory.

 

[brianmoooore]

Wires from either side of the ring twisted together, and inserted into terminal of socket. Clamp screw works loose, or never tightened in the first place, and cables pull out of socket.
Ring will still test OK, but there will be no voltage from the socket.

 

[telectrix]

By definition if an accessory on a ring is without power, it is a fault on the ring.

The key here is not to assume anything... if one socket is without power then you may or may not get values for the little r's. It's entirely possible that the conductors are twisted together (thus maintaining the end to end continuity) but are just poorly terminated and have thus pulled out of the socket or aren't making a good enough connection resulting in a serious voltage drop at the affected socket when placed under load. Of course the switch could also be bad, or the internal components of the socket could have failed.

If only one socket is without power on a ring I would start there... I probably wouldn't do end to end checks until after I'd investigated the one place without power. If multiple places are without power then you have to narrow it down a little and end to end checks are a good place to start because then you'll know whether which conductor you're looking at for bad connections... it won't tell you how many bad connections but it's a step in the right direction as you'll learn a bit more about the fault.

There are a lot of possibilities... but if the end to ends are good, then you have to look at what's connected. If they aren't, you still need to look at what's connected and there are ways of getting a handle on where the problem may be by creating a map of the circuit so to speak and carrying out specific measurements at each accessory.

i could have said the same but typing with 2 fingers would tak me all nite.?

 

[HSwizza]

I cannot express how gratful I am for you all to take the time to give possible solutions and explanations. Didn’t expect such thorough answers.
A lot of information to absorb but I do understand all of your advice and guidance.
Thanks all.

 

[ipf]

Hence, when you are installing, never twist your conductors together, even the cpc's.

 

[SparkyChick]

Hence, when you are installing, never twist your conductors together, even the cpc's.

Absolutely. Does my nut in.

 

[PEG]

Absolutely. Does my nut in.

Agreed....and for our American followers,it must do their wire-nuts in...?

 

[Zerax]

Hence, when you are installing, never twist your conductors together, even the cpc's.

So how do you manage to get a single piece of sleeving over them without twisting 'em together ??

 

[DefyG]

So how do you manage to get a single piece of sleeving over them without twisting 'em together ??

As per post #10 you dont! 3/4mm sleeving will go over 2 untwisted or you sleeve them individually.

 

[PEG]

I reckon even if both cables entered together,the sheaths were together,both cpc's were identical lengths,and no future testing was expected....i doubt i would consider the 0.0003 pence saving,of another section of sleeving,a viable economy ?

 

[ipf]

Absolutely. Does my nut in.

It's been doing mine in for forty odd years.
Like Bayeux tapestry.........some made a bleedin' art of it.

 

[Rockingit]

It's also worth considering that whilst you might have a continuous end to end r1, r2, rN, if someone has reverse polarity wired a socket then you'll get a false reading - no volts L to E at the socket, but an appliance plugged in will most likely still work L - N (N - L). I had this very thing on an EICR a couple of weeks ago - blew the fuse in my tester when I found it!!

 

[GBDamo]

Hence, when you are installing, never twist your conductors together, even the cpc's.

Twisters and single sleevers, a special circle of hell awaits them all.

 

[Lister1987]

I cannot express how gratful I am for you all to take the time to give possible solutions and explanations. Didn’t expect such thorough answers.
A lot of information to absorb but I do understand all of your advice and guidance.
Thanks all.

Drop @Dan @Lou or @westward10 a PM and Joon our trainees section, more helpful bits in therr