Earths for consumer units

[JamieG]

Hi, When an elecrtrician fits a new circuit breaker consumer unit to replace the existing fuse unit, does the earth have to be fitted to a water pipe?
This would entail drilling a hole in the understairs cupboard wall, and laying the earth across the kitchen to the pipes.
JamieG

 

[ricicle]

If not already in place there should be a 10mm² earth wire connected to the incoming water supply as near as practicable to the stopcock (usually within 600mm)
This is called main protective bonding and also applies to gas, oil or any other incoming metallic service.

 

[PrenticeBoyofDerry]

The only time you wont see the pipe work bonded, is if it's all plastic and I mean all.

 

[ban-all-sheds]

In other words...

This would entail drilling a hole in the understairs cupboard wall, and laying the earth across the kitchen to the pipes.

OK.

 

[jobin]

Does this 10mm earthing wire to nearby water pipe relate in size to the incoming line capacity? My CU is 60 Amp max so must i also use 10mm earthing wire? See related Q in nearby forum. Tnx.

 

[JohnW2]

Does this 10mm earthing wire to nearby water pipe relate in size to the incoming line capacity? My CU is 60 Amp max so must i also use 10mm earthing wire? See related Q in nearby forum. Tnx.

Yes, it still needs to be 10mm².

Just to be clear, it is not 'to a nearby water pipe'; it should be to the water pipe near (ideally within 600mm) of the water meter or where the pipe enters the property.

Kind Regards, John.

 

[EFLImpudence]

Does this 10mm earthing wire to nearby water pipe relate in size to the incoming line capacity?

This is called the Main Protective Bonding.
Not the capacity as such but the actual size of the incoming cable (although, obviously, the two are related).
However, most electricians will fit 10mm² as a matter of course to 'future proof' if not actually required to be that big for your installation.
The '10mm²' is the cross sectional area of the copper not the diameter of the wire.

My CU is 60 Amp max so must i also use 10mm earthing wire?

This is called the Earthing Conductor.
Again, it's related to the size of the incoming cable and today will be 16mm² but as above will be fitted as a matter of course to 'future proof' if not actually required to be that big for your installation.

Edit - Getting posters muddled, just noticed where you live so not sure if regulations are the same.

 

[JohnW2]

My CU is 60 Amp max so must i also use 10mm earthing wire?

This is called the Earthing Conductor.
Again, it's related to the size of the incoming cable and today will be 16mm² but as above will be fitted as a matter of course to 'future proof' if not actually required to be that big for your installation.

My reading was that the poster was still asking about the Main Bonding Conductor here. As you said, in practice that would usually be 10mm². Per BS7671, it needs to be at least half the size required for the Earthing Conductor (but no less than 6mm², and no less than 10mm² if it is a PME supply).

Edit - Getting posters muddled, just noticed where you live so not sure if regulations are the same.

I hadn't noticed that, either, so the same comment relates to my posts.

Kind Regards, John.

 

[jobin]

Well, am truly sorry but can't now see how the 'proper' thing can be done. A good bit already done, can't be re-done. I have read more and here is what i can do, hoping no future troubles. No water pipes within 10m of CU so must run the 6mm earthing connector thru the conduit with at least 3 choco-connectors to the water pipe. The 6mm is already in place. Codes here very similar to former colonial power, UK. But in my case, like many expats, communication with local folk limited so can't ask many questions and shops only marginally serve my needs. Thanks all for inputs and advices.

 

[ban-all-sheds]

Well, am truly sorry but can't now see how the 'proper' thing can be done.

Then you need to get an electrician who can.

A good bit already done, can't be re-done.

Yes it can.

No water pipes within 10m of CU so must run the 6mm earthing connector thru the conduit with at least 3 choco-connectors to the water pipe.

Why connectors?

It should be a continuous length of cable.

The 6mm is already in place. Codes here very similar to former colonial power, UK.

And what does your code say about the size for main bonding conductors?

Another thing which is very similar, in fact the same the whole world over, is that you should find out what you need to know before you start doing, and ending up with things you don't want to re-do even if they need it.