Neutral link to earth | on ElectriciansForums

Neutral link to earth

Post new thread

Discuss Neutral link to earth in the UK Electrical Forum area at ElectriciansForums.net

R

rantoftheday

Can someone tell me why on certain installation where a main earth ain't in place ie domestic property why can't an earth be taken off main incoming neutral as a tn-c-s system instead if installing a tt system?
 
Last edited by a moderator:
Sort by date Sort by votes
To system? I'm guessing you mean TT mate but please clear that up.

In a lot of cases the DNO does not supply an earth facility, this is why TTs exist because if an earth is not supplied it has to be put in place by us. DIY TN-C-S systems are not the way forward
 
Upvote 0 Downvote
But effectively would a tn-c-s system installed by a qualified spark not work as well, if not better than a TT system? Plus saves the hassle of putting in earth rod(s) running cables to db and putting in type s RCD etc
 
Upvote 0 Downvote
The DNO have to convert to a TN-C-S how does a spark coming into a job know if PME is available. There is more to it than just joining N&E together in the service head.
 
Upvote 0 Downvote
It may well work better than a TT mate but what you have to remember is that if you do a DIY TN-C-S you're messing with the DNOs toys. If anything were to go wrong with it it's going to be you that's in a big wooden panelled room with blokes in wigs explaining why you did what you did when you had no right to do that. On the other hand it may not work well at all and you could fry people.
Is it really that difficult to install a decent rod system? I'd say not. It's always worth a call to them to see if PME is available in a particular area but sometimes you're going to be told no in which case, since you're the apprentice hehe, you'd best get swinging that hammer
 
Upvote 0 Downvote
Great reply trev. Tbh it was purely a curiosity question. I don't swing hammers no more mate we have a younger apprentice now ha. By the looks of your pic been a while since you've been swinging hammers! Unless your the little un in the pic! Ha cheers for the answer buddy all the best
 
Upvote 0 Downvote
It's always good when a newer apprentice turns up because he then gets the crappier jobs which you used to enjoy so much, sadly now I'm self employed I have to do all the hammer swinging, and the bloody sweeping up, getting the sarnies....bloody hell it's like a second childhood:)
No mate, the little un in the pic is my grandson and newset apprentice, 2 years old come Monday and he was "helping" me with a couple of jobs round the house today.
 
Upvote 0 Downvote
The additional source earths are what need to be installed before a system can be changed to TN-C-S
 

Attachments

  • [ElectriciansForums.net] Neutral link to earth
    image.jpg
    122.9 KB · Views: 99
Upvote 0 Downvote
If you combine earth to neutral on a standard TT system it will work fine and dandy but under certain fault conditions it can be lethal - - -a neutral break anywhere on the supply cable could make all the earthed metalwork live....
Hence a very dangerous situation for everyone.....
When they convert a TT to TNCS they strap N to earth at every available point hence PME stickers 'Protective MULTIPLE Earthing'.... this in turn gives a very low risk that the return N/E path is lost ever as a break will have multiple return options.


As Sintra says there is alot more to it than even i have explained but it shows how dangerous converting it yourself can be as well as illegal.
 
Upvote 0 Downvote
If you can aprenticesprky, print out that diagram that Frank posted. It's one of the best pictorial explanations I've seen of a TN-C-S earth path in a long time.
I'll see you after me ban expires :)
 
Upvote 0 Downvote

Reply to Neutral link to earth in the UK Electrical Forum area at ElectriciansForums.net

Similar threads

J
UK Main Earth and Gas Bond
Indeed it would be. But that would mean having 2 things to disconnect instead of one. More margin for error. Of course, any diligent spark would...
Replies
6
Views
582
loz2754
L
D
UK Swa as main earth ?!?
You would treat it as a TT installation.
2
Replies
29
Views
1K
westward10
westward10

OFFICIAL SPONSORS

Electrical Goods - Electrical Tools - Brand Names Electrician Courses Green Electrical Goods PCB Way Electrical Goods - Electrical Tools - Brand Names Pushfit Wire Connectors Electric Underfloor Heating Electrician Courses
These Official Forum Sponsors May Provide Discounts to Regular Forum Members - If you would like to sponsor us then CLICK HERE and post a thread with who you are, and we'll send you some stats etc

YOUR Unread Posts

This website was designed, optimised and is hosted by untold.media Operating under the name Untold Media since 2001.
Back
Top