Connection to Neighbour

Using an extension lead core as a main bonding conductor might have its disadvantages - as I guess it's a lot smaller than the size usually required (perhaps 1.0mm2 instead of 10mm2) - and if depending on the details of the situation could end up carrying network diverted N currents - which could be significant especially if the DNO's network is suffering from disruption rather than being completely dead - probably the worst case being a broken CNE event.

I guess another option would be to use the extension lead to supply the fridge alone and not to connect it to the bonding in the neighbouring property - so you'd end up with a situation rather like using class I equipment outdoors - far from ideal - but the sort of thing that goes on quite often without there being any huge piles of bodies in the street.

The risks probably depend on the connections between the two properties - if they're closely connected to the DNO network or better still have bonded shared metallic services - they're likely to be in effect all part of the same extend ‘equipotential zone’ anyway so the actual risks might be minimal.

   - Andy.

People have died doing things like this, because of issues with the generator and issues with the extension lead.

It depends rather how it is done. If it was literally a lead to the fridge - a plug at the genset end and a socket for the fridge to eb unplugged from the wall and plugged into the lead,  it should  be fine - or at least the sort of thing that may be trouble would be trouble for house with the genset too. 

Do be clear how if the external mains supply and earth connection are missing, the genset still gets an earth to terra-firma and an NE bond.

But apparently easy things, like a lead with a plug at each end to feed power into the neighbour's ring for example,  and yes, some folk really are that daft, can end very badly.

More detail on how it will be done is needed.

Mike.

I cannot see any problem with unplugging the fridge and plugging it into an extension lead - whether the lead is going to the neighbour or the shed at the bottom of the garden is irrelevant.

More problematic might be something with bonding, such as a CH boiler.

What you definitely don't want is the possibility of connecting the two installations' lines together - they are likely to be on different phases.

mapj1: 
 

It depends rather how it is done. If it was literally a lead to the fridge - a plug at the genset end and a socket for the fridge to eb unplugged from the wall and plugged into the lead,  it should  be fine - or at least the sort of thing that may be trouble would be trouble for house with the genset too. 

Do be clear how if the external mains supply and earth connection are missing, the genset still gets an earth to terra-firma and an NE bond.

But apparently easy things, like a lead with a plug at each end to feed power into the neighbour's ring for example,  and yes, some folk really are that daft, can end very badly.

More detail on how it will be done is needed.

Mike.

Thank you everybody.

I,ve  added a sketch to the original post.

In theory there are risks, including.

The fridge or other class one appliance will be disconnected from the earth system in the second house, but instead connected to the earth rod at the first house. Under fault conditions, there could be a dangerous voltage between the fridge and some other appliance in the second house.

In practice I would consider the risks to be small and arguably acceptable for short term use.

I MIGHT consider it safer to use a 2 core extension lead with no CPC. This avoids all doubt about differing earth systems and voltages between them.

Use an RCD socket outlet on the far end of the extension lead to give protection against insulation failure in the fridge.

Sparkingchip: 
 

People have died doing things like this, because of issues with the generator and issues with the extension lead.

If you have a look through the records for deaths by electrocution and carbon monoxide poisoning you will realise that is not a throwaway comment.

When the power is restored in house 2 the zones are clearly breached, they probably are anyway.

Sparkingchip: 
 

When the power is restored in house 2 the zones are clearly breached, they probably are anyway.

What 2 zones ?  - they will be on the same substation, so nominally the same equipotential zone, at least from a DNO perspective, and presumably if the street mains for water etc are metal, solidly bonded at the MET too.

They may be on different phases, do not connect them !! 

Yes, there are disproportionally slightly more accidents with gensets, but that is also because they mostly get used in an emergency, and the kit is often not maintained between uses, and it is seldom, so folk forget what to do and do things in the wrong order or forget parts of the process, such as arranging exhaust ventilation . (and a few tragically silly ones involving  fires refuelling petrol sets while the engine is running. )

In terms of both fire and CO diesel is vastly safer.

M

 

The next-door neighbours do not have a standby generator and the question was raised that, in the event of a mains power loss, would it be OK to run an extension lead from the Standby Generator fed installation to supply, say, the neighbours fridge?

I

I installed the same changeover arrangement for a 3kW generator in my house, about 6 years ago. There is an RCD installed on the house DB for sockets. It would be possible to give a close neighbour an extension from a 13A socket on the house RFC, with a low rated fuse but “Close enough to be neighbours but too distant to be friends”. Most freezers will survive for 24 hours with no power though if not opened too much; mine has a thermometer on the outside of the door for the common fridge and one for the freezer. ?       

Jaymack