Melting fridge lead whilst shower is on

[colin74]

Hi there

Was having a shower this morning wife was down stairs she put the kettle a minute later she smelt fishy smell which she new was electric burning smell ...she discovered the fridge lead that was plugged into the same double socket as kettle was melting ....I don't believe it an issue with the socket . We have suffered a similar issue in the past it only happens when we have lots of high load devices running at the same time usually the shower will be on...also the lights dip in the house when the shower is on ...the wiring in the house looks to be okay I feel this May be a consumer unit issue can any one advice?

 

[HERTS P&D]

Get an electrician in asap to check things over.

Andy

 

[ban-all-sheds]

Get an electrician in asap to check things over.

Left to evolve naturally, the next stage could be an actual fire, and you probably don't want that.

 

[viewer]

As above, but don't use the FF. According to London Fire Brigade they are the cause of a very large number of domestic fires.

 

[Taylortwocities]

Probably nothing to do with your issue buit worth a read.
http://www.which.co.uk/news/2011/07/fire-warning-to-500000-fridge-freezer-owners-257964/

I'm expecting a loose connecting to have caused your problem, either in one of the plugs or in te fixed wiring to the socket itself.

 

[JohnW2]

As above, but don't use the FF. According to London Fire Brigade they are the cause of a very large number of domestic fires.

We've been through that before. IIRC, they don't say that FFs are a common cause of domestic fires (which I rather doubt would be the case) but, rather, talk about the consequences of FFs becoming involved in domestic fires.

I think we're all agreed that the OP needs an electrician ASAP.

Kind Regards, John

 

[stillp]

Is anybody else thinking that the socket has been inserted in the shower radial, or that the shower is connected to the ring final?

 

[Lectrician]

Sounds like a high resistance PME to me. Coupled with a N to E fault in the fridge. Seen this a couple times (not in a fridge!).

 

[westie101]

Sounds like a high resistance PME to me. Coupled with a N to E fault in the fridge.

Certainly a high resistance neutral with an L - E fault

 

[JohnW2]

Is anybody else thinking that the socket has been inserted in the shower radial, or that the shower is connected to the ring final?

Although it's clear that something nasty is going on which needs urgent attention, I could not really make much sense of what we were told. I thought of scenarios such as you mention, but nothing like that would result in the fridge's cable (I take to mean the flex from socket to fridge) to overheat. For that to happen would surely require that the shower was being fed from the fridge end of the fridge's flex,or something like that, wouldn't it?!

Kind Regards, John

 

[Lectrician]

Not with a N to E fault in the fridge, a high resistance supply neutral, and a parallel earth path due to gas or water.

 

[JohnW2]

Not with a N to E fault in the fridge, a high resistance supply neutral, and a parallel earth path due to gas or water.

Agreed, given that combination of circumstances.

Kind Regards, John

 

[Lectrician]

I have seen the results of dodgy neutrals a good few times in various different circumstances - none of them nice. Think I have some photos somewhere.

Never seen an appliance cause this, but it could happen.

 

[JohnW2]

I have seen the results of dodgy neutrals a good few times in various different circumstances - none of them nice. ... Never seen an appliance cause this, but it could happen.

I would guess that the situation is only likely to arise if the N-E fault within the installation (wiring or appliance/equipment) pre-dates the appearance of the high supply neutral resistance ...

... to get (as is being postulated in this case) very high currents flowing from the installation's neutral (from loads) through an N-E fault and a low resistance path to earth (bonded extraneous-c-ps, or perhaps a TN-S earth) requires that the impedance of the faulty supply neutral has a considerably higher impedance than that path through the N-E fault. If the supply neutral had had as high a impedance as that prior to appearance of the N-E fault, I would imagine that the considerable voltage drop in the faulty supply neutral would have already brought that problem to the occupier's attention (dim lights and appliance/equipment malfunction etc.).

For example, I would guess that the neutral impedance would usually have to be at least an ohm or two to create the situation we're postulating - so that, in the OPs case, had that fault been present prior to the NE one, switching on the shower would probably have resulted in a drop of 40V - 100V is the installations L-N voltage - which would surely not have gone unnoticed. Is my thinking reasonable?

Kind Regards, John

 

[Lectrician]

You would think so wouldn't you, but every case I have seen, the customer has said things linke "ah, that's why the lights have been flickering", and things like that.