Earthing question

steveeeee

Hi all,

My parents are having some wiring done on a small extension that's being built. They had a bit of a scare from their sparky last week when he told them that the existing wiring in the house is unsafe as it's not properly earthed. My dad's asked me to post this question on here for him:

The wring regulations say that, for a house with earth-rod (TT) connection, the consumer unit should be connected to both the water and gas service pipes, at points on the house side of the stopcocks. Does this apply when the incoming water service is in plastic pipe? When there is a fuel-oil supply instead of gas, should the consumer unit be connected to the incoming oil pipe?

Any advice would be much appreciated.

amarg

Main equipotential bonding is not difficult to understand and basically involves running a 10mm2 Earthing wire from either the Main earthing terminal or the Earthing bar in the consumer unit and should be securely clamped to the incoming metal water, gas and Oil service pipes using a suitable Earth clamp. The main bonding must be carried out on the customers side of any meter, Main stopcock or insulating insert and must be connected within 600mm of either the first valve, or the entry point to the premises.

Taken from here-

http://www.ultimatehandyman.co.uk/earthing_main.htm

baldelectrician

The (Main) bonding may even be 6mm in a TT system, most sparks use 10mm as this is 'normal'

Why do they have a TT system?

Can it be converted to PME?

Some local elec companies do this for free, some do it for < £80. Some couldn't care less (isn't fragmentation of the industry great- same standards different opinions)