This discussion is locked.

You cannot post a reply to this discussion. If you have a question start a new discussion

Earthing and Bonding

Former Community Member over 4 years ago

Hi All

Working on a scheme whereby we have a private transformer serving the site - TN-S arrangement. This comes into the building, we then split to feed a switchboard in one part of the building which is existing, the second split heads to a new build part which has the second switchboard. This new build contains swimming pool. The supply to the new switchboard is via a busbar 3L+N+PER. Question relating to earth bars - we currently have the main earthing bar at the intake point which is at the existing switchboard location - we then had cable feeding out to the new earth bar at the new switchboard location. Contractor is proposing that they remove this interlinking earth cable between bars, and take a bond directly from the new switchboard earth bar to the new earth bar in the room. Does this sound feasible - to me doesnt sound right, but I can't find anything specific to say not.

Many thanks

Parents

0 tattyinengland over 4 years ago

I am no expert so take my answer with a pinch of salt....

I believe that if you want to take the bonding for the swimming pool from a remote sub distribution board, the earth for that sub distribution boards supply needs to be sized for both Earthing and bonding.

Quite a few years ago - like 10 or 12 - I asked a similar question on the old platform for this forum and I was given a series of brilliant replies - mostly by the same guys who haunt this forum now - and they went on to explain and expand on this statement.

Now I'm sure if I tried hard enough I could expand on that satement - but darned if I can explain it at the moment....at the time it was explained very well, I did the necessary calculations and installed the cable, but I cannot for the life of me remember what I did. I've forgoton. (The NICEIC area inspector even checked it - so it was done properly)

So I'll put my ignorance out there

- being sized for earthing - I can work this out

- being sized for bonding - I can work this out

Being sized for both earthing and bonding.......... well now what - add the two sizes together I suppose. I know asked this same question last too............darned if I can remember the answer.

I'm sure one of the guys will expand on my answer soon.
Cancel
Vote Up 0 Vote Down

Cancel

Reply

0 tattyinengland over 4 years ago

I am no expert so take my answer with a pinch of salt....

I believe that if you want to take the bonding for the swimming pool from a remote sub distribution board, the earth for that sub distribution boards supply needs to be sized for both Earthing and bonding.

Quite a few years ago - like 10 or 12 - I asked a similar question on the old platform for this forum and I was given a series of brilliant replies - mostly by the same guys who haunt this forum now - and they went on to explain and expand on this statement.

Now I'm sure if I tried hard enough I could expand on that satement - but darned if I can explain it at the moment....at the time it was explained very well, I did the necessary calculations and installed the cable, but I cannot for the life of me remember what I did. I've forgoton. (The NICEIC area inspector even checked it - so it was done properly)

So I'll put my ignorance out there

- being sized for earthing - I can work this out

- being sized for bonding - I can work this out

Being sized for both earthing and bonding.......... well now what - add the two sizes together I suppose. I know asked this same question last too............darned if I can remember the answer.

I'm sure one of the guys will expand on my answer soon.
Cancel
Vote Up 0 Vote Down

Cancel

Children

No Data

Earthing and Bonding

Community Rules & Guidelines