Earth Bonding Ask questions and find answers to many subjects relating to electrics and electrical work

[WHYDIY]

What size cable do I need when installing the primary earth to the stop tap and gas meter to the meter box?

This may have been covered before for that I apologise.

Many Thanks M

[BLAKEY1963]

[quote="WHYDIY"]What size cable do I need when installing the primary earth to the stop tap and gas meter to the meter box?

This may have been covered before for that I apologise.

Many Thanks M[/quote]


WHYDIY
EQUIPOTENTIAL bondind to water and gas supply is usally 10 mm2. your electrician . would b glad 2 offer free advice.
BLAKEY1963

[kbrownie]

It's relative to the supply type and the conductor sizeof supply neutral 10mm CSA is normally okay, TT and TN-S system sometimes smaller.

Installing or updating main or suplementary equipotential bonding likely to be okay as far as part p is concerned "grey area!" But I'm sure if this in special location or kitchen it needs notifying or part p electrician employed to do work.
KB

[craigmac1878]

Hi, right new to this forum,

Just going for my 17th edition real soon, was just wondering about
an issue with earthing the main stop tap from the fuse board, as I heard in conversation
the other day, that in a new extension build, the main water does not need to b e earthed and that only
The hot and cold pipes and possibly the sink need to be earthed, is this true?

[moggy1968]

complete rubbish I'm afraid!!!
If the rest of the installation is upto 17th edition standards (in the bathroom and kitchen) and certain other criteria are met then there is no requirement for supplementary bonding. your main bonding however always has to be in place and that is connected to the main water and gas, immediately after the supplers meter or, if that is outside, within 600mm of the point of entry into the building.
it sounds like you've got your supplementary (equipotential) and main bonding mixed up.

[kbrownie]

craigmac1878,
I'd like to know where this information came from?
The incoming mains water supply should be bonded to either the MET or the CU depending on your earthing system. This should be within 600mm of entering the property.
No requirement to Supp bond sink.
This is to create an equipotential zone within the property, the water supply could well be delivered to the property via plastic pipework but that is outside equipotentail zone.
The installation will be tied to the mass of earth via MET to earth supply or CU to electrode. If all exposed metal work are connected via bonding this will raise the potential to the same level in the event of a fault.
I can understand it if all the pipe work is plastic but that would then eliminated the risk.
KB