What does Earth Bonding involve?

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vonsworld

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Hi
I have an old style fuse box and would like it upgrading to a modern trip switch consumer unit. However it appears that there is only one earth connection in the house which goes to the main incoming supply cable, so an electrician would also need to improve and bond the earth.

What does earth bonding involve please?

The CH boiler is in the airing cupboard with access to the central heating and hot/cold water pipes. Would bonding these pipes to the earth be enough to satisfy the current regulations?

Any advice is appreciated :-)
 
Main Protective Bonding bonds (joins) to the electrical supply earth any items (Extraneous-Conductive-Parts) that are liable to introduce another potential by being in contact with other earths, e.g. the ground.

Old or new consumer unit makes no difference to the requirement.
It might be that your existing installation has no ECPs.
 
Thanks for your reply.
If I have the consumer unit replaced then I presume the electrician would also be required to upgrade the earth and install bonding if required to meet current regulations?
So I can't just have the consumer unit replaced if the earth is below current standards...
 
Yes.

They are required to connect (thick!) cables to supply metal water and gas pipe.
At the point they enter the house
 
Thanks, so they can't bond it in the airing cupboard where all the pipes converge, they need to go back to the actual point of entry and then run a new earth wire all the way to the consumer unit?

One final question... the house has no earth on the lighting circuit, since this was not required when it was built in 1968. The cables however are all modern type plastic coated. I presume there is no requirement to have an earth fitted to these?

Thanks and have a good day
 
vonsworld said:
Thanks, so they can't bond it in the airing cupboard where all the pipes converge, they need to go back to the actual point of entry and then run a new earth wire all the way to the consumer unit?
Click to expand...
Correct.

One final question... the house has no earth on the lighting circuit, since this was not required when it was built in 1968. The cables however are all modern type plastic coated. I presume there is no requirement to have an earth fitted to these?
Click to expand...
Well, that is up to you, but the electrician might not be keen on the idea.
The cables can't be that modern. You must only use plastic switches and light fittings.
 
Why are you apparently against having the bonding fitted (it should be there already IF required) yet want a new consumer unit?
 
I don't think bonding would have been commonly fiitted in 1966
Even if it was, it would not be thick enough to meet todays requlations

1966 lighting circuits would not rrequire earths (unless metal fittings were used, e.g flourecesnt tubes)
An electrican could put a sticker on the new CU stating lighting circuits do not have CPC (to cover it)
 
I thought a new consumer unit would be a good idea because rcd's are a lot more sensitive and trip out more quickly than old style fuses. So just wanted to assess what extra work might be involved.

If it's too disruptive and expensive and the electrician insists on making changes to the lighting system too, then I just won't bother.
 
well, it sounds like you have concerns about the safety of your installation, which is fair enough given its age. Although MCBs and RCDs seem very clever, they still can't prevent all dangerous situations, hence the regs cover a lot more than just the consumer unit.
I'd recommend getting a couple of electricians in who seem to know their stuff, get a quote to bring things up to a standard they'd be happy with, and report back here if you're not sure.
Personally I'd be upgrading the bonding to current standards before going ahead and changing fuses to MCBs, because fuses work almost exactly the same as MCBs. The RCDs would provide extra protection that is required nowadays, but even that would be behind correct bonding in my mind. Just because bonding is just a piece of wire doesn't mean it's not saving lives.
 
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