Earthing of a remote sub consumer unit

[flattop]

Hi I need to fit a sub consumer panel (I am not sure if that is the correct term) in a seperate outbuilding, from the main consumer unit in the house.
(a)Do I need to run a 3 core with earth, so that it is earthed at the same point as the house? or
(b)can I run a 2 core and use the earth on the outbuilding, which is good?
It is about 20m away.
any advice would be most welcome. Thanks in avance. Jane

 

[malcolmsanford]

There are pros and cons to both methods.

If the house is a TN system and you intend to extend the equipotential zone out to the outbuilding, then yes maybe worth considering running a 3 core out if you have water/gas services. Using a 3 core 10mm, you could use the 3rd core as a bonding conductor and the SWA as your CPC.

If you have already a TT earth for the house, then I would most certainly run a 2 core and rod the outhouse and tie the earthing rods together via the SWA CPC.

 

[flattop]

thank you very much I think I understand except what is a cpc and SWA? Sorry to be so ignorant! Jane

 

[telectrix]

cpc -- circuit protecfive conductor. SWA -- steel wire armoured (cable). i would however question your ability to complete this job, going from your posts. it is notifiable work ( assuming you are in england (12) or wales (19))

 

[SimpleSimon]

Hi I need to fit a sub consumer panel (I am not sure if that is the correct term) in a seperate outbuilding, from the main consumer unit in the house.
(a)Do I need to run a 3 core with earth, so that it is earthed at the same point as the house? or
(b)can I run a 2 core and use the earth on the outbuilding, which is good?
It is about 20m away.
any advice would be most welcome. Thanks in avance. Jane

When you say earth on the outbuilding?Cant understand what you mean exactly??

Sent from my GT-I9100 using Tapatalk

 

[flattop]

Thanks for the information, and don't worry, I am not going to do the work. I just wanted to check the best approach before commissioning it. Cheers, Jane.

 

[flattop]

Its a large post driven into the ground to attach earthing wires to. Reading 42ohms.

 

[Engineer54]

Nothing to stop you connecting this earth electrode, to any earth system your bringing to this outbuilding. If the house earthing system is PME/TNC-S, then you would need to run a 3rd core 10mm if there is any water service incorporated in this outbuilding. But you can still incorporate this existing earth electrode into your system.....

As others have mentioned you don't seem to be too sure of what your doing, so i strongly recommend you employ a qualified electrician. You can always come to some arrangement such as you providing the cable trench etc, which will reduce the cost of employing a qualified electrician. Remember, it can be substantially cheaper to employ a Part Pee electrician than to do this work yourself and notify yourself!! Just to notify the LABC could set you back 250 quid!!!

 

[Mr Mike]

cpc -- circuit protecfive conductor. SWA -- steel wire armoured (cable). i would however question your ability to complete this job, going from your posts. it is notifiable work ( assuming you are in england (12) or wales (19))

Very good tel