socket no power

[rego]

My son called about 4 weeks ago saying his fridge freezer had stopped working. Single socket, only one cable unsure where it is fed from. He tried another appliance in socket but didn't work either. He plugged fridge into extension reel and has worked ok since then. Nothing tripped in consumer unit. No lights come on when socket tested with plug in socket tester. New faceplate fitted on socket but still no power. Is this ok to leave with fridge plugged into extension cable?

 

[ericmark]

The worry about using an extension cable with a refrigeration unit is the volt drop will mean the pressure builds up, before the motor has reached full speed, and it will cause the motor to stall.

For this to happen the extension would need to be very long and for the voltage to home to be on the low side to start with. So in real terms unlikely to happen.

If the unit starts up OK, then there is no problem.

 

[pete01]

Fixing the faulty socket is probably the best bet.

 

[ericmark]

I do remember in my parents house, hunting for why a socket did not work, I found my dad had fitted a fused connection unit (FCU), feeding another FCU and one was under the counted hard to see.

So I can see how hard it is to find the problems sometimes.

The worry is if part of a ring final and the fault is breaking the ring. This can cause an overload in one leg, so unless we know that is not the case, we do tend to spend a lot of time inspecting and testing to make sure no danger.

So as @pete01 says, fixing the socket is best. But you asked about use of an extension lead, and there is no real problem other than what I have already said, and the trip hazard.

I would remove the socket, and see how many cables feed it, if only one, then not likely part of a ring final, if two then more worrying, and you need to look further. Since a freezer, it was common to fit switches to sockets supplying freezers so it could be turned off without moving the unit, where the unit its self was in front of the socket, to get 20 amp rated switches, it was common to use grid switches, these also allowed on to get switches with a legion on them. It could also combine a fuse holder and switch. Or a row of switches

supplying other items which are in front of their sockets, it was considered important with washing machines, as there was a fault where the weights we made slightly undersize, and the fact was masked by flashing on the concrete, when this flashing powered off, the washing machine could vibrate around the room, so wanted a way to turn them off, without touching it. Today they have out of balance sensors so auto turn off.

 

[JohnW2]

The worry about using an extension cable with a refrigeration unit is the volt drop will mean the pressure builds up, before the motor has reached full speed, and it will cause the motor to stall.

Theoretically, perhaps - but, as you go on to say ....

For this to happen the extension would need to be very long and for the voltage to home to be on the low side to start with. So in real terms unlikely to happen.

... which I think probably translates to it being extremely unlikely that there would be any problem in the real world.

 

[rego]

Thanks for replies. Only one cable feeding the socket in question. I suspect it may be a spur off another socket. I am visiting my son in 3 weeks time and will try to find out. Do you think its ok to leave for now?

 

[jj4091]

Yes

 

[foxhole]

In a modern kitchen appliance sockets for fridge , DW, WM etc are switched from another accessible location . May have accidentally been turned off, I was always being called to a “broken fridge” in the office , staff just kept stacking heavy boxes against the isolation switch turning it off .

 

[Deleted member 310928]

The worry about using an extension cable with a refrigeration unit is the volt drop will mean the pressure builds up, before the motor has reached full speed, and it will cause the motor to stall.

What about a spur, supplied from the furthest point away from the ring, being several meters away?

 

[Deleted member 310928]

He plugged fridge into extension reel and has worked ok since then.

Extension reel plugged into the same socket, or extension reel plugged into a different socket?

 

[rego]

different socket

 

[Deleted member 310928]

different socket

With the socket now replaced, assuming it was done correctly, it’s either a FCU, which controls the fridge, accidentally switched off, or the fuse blown, or a loose wire.

But there is no guarantee that it’s supplied from a FCU, or if it’s been spurred off the ring. Just by seeing one cable supplying the socket can indicate that it’s the final socket on a radial circuit.

 

[CountryFan]

With the socket now replaced, assuming it was done correctly, it’s either a FCU, which controls the fridge, accidentally switched off, or the fuse blown, or a loose wire.

I don’t think there’s a mention of the “faulty” socket being replaced. I’m of the same opinion with it being an fcu that’s inadvertently been turned off

 

[ericmark]

What about a spur, supplied from the furthest point away from the ring, being several meters away?

We are required when installing a socket to test it, for the volt drop we are looking for a line - neutral loop impedance increase of less than 0.6 Ω to the incoming supply with a ring final, but the line - earth for a ring final or any spur from a ring final should not be more than 1.44 Ω even before the drop to 1.38 Ω, with a radial again we have limits.

So any installed socket must comply with the regulations, but an extension lead is not installed, there are still limits, this may have changed, but 2008 the max loop impedance for a 13 amp fuse was 2.42 Ω, so we should have a limit of 1 Ω for an extension lead, however if we are using RCDs then the line - earth loop impedance can be higher, but we all know these

extension leads will exceed the resistance permitted without RCD protection, and to pass a PAT test it would need a RCD plug in the days before all sockets were RCD protected.

So with an installed socket we can be reasonably sure it was tested when installed, even if just a simple socket tester

with loop of course, but with an extension lead it could escape being tested.

 

[Deleted member 310928]

I don’t think there’s a mention of the “faulty” socket being replaced. I’m of th same opinion with it b in an flu that’s inadvertently been turned off

New faceplate fitted on socket but still no power.

Did rego mean socket when he said that?

Or did it mean that he tested another device, and that faceplate, which is what he referred it to, was for a different plug? But looking at this, I don’t think that’s what it was.

He tried another appliance in socket but didn't work either.