Ring Fault NO RCD-trip

[user 28181]

Ring circuit (5 2-fold plug sockets) intermittently losing power (to all sockets) without tripping the RCD.

Am I right in thinking this "must" be a loose terminal at the origin of the ring, or even earlier e.g. where the ring root comes off the RCD board?

Is this a fault I can have a crack at myself (non-electrician, know enough to turn off the circuit at the board, how to use a screwdriver)?

Is there any danger of a short/fire, given the symptom?

Should I get an electrician in? After I've had a go? ASAP?

Thanks so much!!!

 

[leesparkykent]

is it tripping the circuit breaker?

 

[user 28181]

no

 

[Murdoch]

How do you know it's a ring?  Power loss could be a neutral fault.

 

[user 28181]

I say it's a ring because it's labeled that way on the circuit breaker box. Could be not-a-ring, I suppose.

I also understand that it's pretty much standard to set up multi-sockets on a single storey as-a-ring.

Is there any easy way to find out, other than pulling the house to pieces?

(I guess testing conductance/resistance between sockets would do it; unfortunately, don't have kit to do that ...)

Scuse my ignorance, dont understand the "neutral fault" bit.

I'm inferring that you're saying:

- all these sockets might *not* be on a ring

- then, some problem on a single neutral wire could then cause them all to lose power at the same time.

Can you explain a bit more? (e,g, some problem on a single *live* wire could also cause the same fault, no?!)

How would I test for what-you're-suggesting?

Thanks!

 

[Murdoch]

A neutral fault means the sockets are live! Please don't fiddle. Ideally you need an MFT and competence to use it.

Has anyone been fiddling with it recently?

 

[sparkytim]

If it is a Ring final circuit then you most likely have 2 faults, possibly loose connections.

Do all the sockets go off or just a few of them?

Suggest TURNING OFF the supply and checking ALL socket connections.

 

[binky]

 a neutral fault can make the sockets look dead, that' why they are dodgy to fault find. But if you feel you can safely isolate the cct before fiddling, chances are a loose connection either in the live or neautral.

 

[Andy™]

and if you do find a fault then keep looking. as already pointed out, it will take 2 faults on a ring to loose power

 

[user 28181]

I understand that there can be voltage-at-sockets even if appliances-don't-work: I don't interpret "appliances don't work" as "there's no voltage here".

I always switch off twice at the circuit board (breaker, and rcd) - that should ensure no juice at the sockets?

"Chances are a loose connection either in ..."

OK thanks, that's what I wanted a read on, thank you!

If it's a loose connection in the live, could that *possibly* be a fire risk? Sparking?!

Just wondering how motivated I should be to sort this .. 'spose it's hard to say more than "it could be anything - get on with it"

Appreciate the constructive input and clarification, thanks again

 

[Rob_the_rich]

For both legs of the ring to lose power at the same time (all sockets off) suggests that there might be a loose connection at the mcb feeding the ring (top or bottom screws on mcb), or at the circuit's connection to the neutral bar. To check the tightness of these connections you would need to switch ALL power off, main switch, all MCBs and RCDs, and if you have an isolator switch upstream of the CU, switch that off too. do not touch the metal shaft of the screwdriver when tightening. If you are unsure, please get someone in to look at it. And tell us how you get on. We think the worst when no-one replies

 

[Andy™]

If it's a loose connection in the live, could that *possibly* be a fire risk? Sparking?!

a loose connection in any live conductor can be a fire risk. a live conductor also includes neutral

 

[user 28181]

==> Sparky:

yes, all off.

I hadn't thought of two connections in the sockets themselves.

That's worth checking.

(I *will* turn off everything at the breaker-board, fo' sho').

==> Rob:

yes, exactly - all-go-off-at-once with sockets-off suggests an "early problem".

If the Sparky route yields no results, I'll get a pro to look at the boards: I think that is beyond me.

Thanks again everyone!

==> Andy:

got it, thanks!

 

[ProDave]

I would put my money on the MCB bottom terminal has "missed" the busbar finger.
 

 

[user 28181]

==> ProDave: will let you know! Thanks for the diagnosis