Pme to feed garage.

amicus · Jan 14, 2010

HI Anyone know definate rule on feeding garage from house on pme?I see so many opinions im not sure anymore.Briefly i intend to run a 6mm 3core swa to rcd garage unit,fed from 30a mcb in house.Approx 25m run,and no other services or metal entering garage. Is this ok or are we in earth rod territory.Thanks.

pennywise · Jan 14, 2010

I believe it's mentioned in the electricity supply regulations. ( sorry for lack of detail wasn't 100% sure myself whether it was mention in there)

amicus · Jan 14, 2010

Are you willing to expand on that?

Spudnik · Jan 14, 2010

It is, but, as you say, there are no other services in the garage so there is no reason why not.

However, i always split the earth out at the garage and bang a rod in the ground regardless.

amicus · Jan 14, 2010

That sounds good.Thanks for your help.

andekoch · Jan 15, 2010

As far as I know you can export the earth if the house is on tns or tt but not pme/ tncs.

Deleted member 9648 · Jan 16, 2010

There is no reason at all why a tncs earthing system cant be used for an outbuilding unless the installation includes areas where tncs restrictions apply,ie construction sites,swimming pools temporary installations exhibition stands etc.

Guest123 · Jan 16, 2010

Hi.

A PME system can be exported provided that the either of the following 2 conditions are met

1. There are no extraneous conductive parts within the outbuilding i.e steel frame, water service, gas service etc.

2. If there are conductive parts, then the equipotential zone needs to be extended to the outbuilding via main equipotential bonding conductors sized accordingly i.e a minimum of 10mm2 for each service back to the MET within the house, unless the sub-main is greater than 10mm2 itself.

Personally if there are conductive parts within the outbuilding then I always TT regardless of sub-main size.

amicus · Jan 16, 2010

Thanks for everybodys help.I think i will go with the majority and leave the stake in the van.Out of interest another item of differing opinions would you put an rcbo in the house or rcd unit in garage.Thanks.