Power to outside shed, does it need TT earthing

[haptism]

Hi hope someone can help. The shed in the garden is about 15m away from the house. Its supply is spurred from kitchen ring via a 30Ma RCD/13A FCU, the load side of the FCU (2.5mm flex) runs outside and underground (within metal conduit) to an adaptable box where its joined to 2.5mm SWA which runs to the shed. At the shed the SWA is terminated into a 13A FCU, which supplys' 2 sockets and 2 strip lights.


Does this installation require a TT earth system as a matter of course. As it is now the earthing arrangement is via the CPC (including SWA). The house has TN-S system.

Thanks

 

[Deleted member 26818]

From what you have described, no.

 

[Corbs]

Hi hope someone can help. The shed in the garden is about 15m away from the house. Its supply is spurred from kitchen ring via a 30Ma RCD/13A FCU, the load side of the FCU (2.5mm flex) runs outside and underground (within metal conduit) to an adaptable box where its joined to 2.5mm SWA which runs to the shed. At the shed the SWA is terminated into a 13A FCU, which supplys' 2 sockets and 2 strip lights.


Does this installation require a TT earth system as a matter of course. As it is now the earthing arrangement is via the CPC (including SWA). The house has TN-S system.

Thanks

can i ask why didnt you run the swa from the outside point by the fcu to the shed, seems an odd way to run power to your shed ?????????

 

[haptism]

To update, ive found that exporting the TN-S is not looked at favourably; so does the SWA need to be earthed via the TT.

 

[haptism]

can i ask why didnt you run the swa from the outside point by the fcu to the shed, seems an odd way to run power to your shed ?????????

What outside point ?, sorry not sure what you mean

 

[Corbs]

What outside point ?, sorry Im not sure what you mean

where does your swa start on stop eg starts at your house/where the fcu is and ends at the shed?

 

[Deleted member 26818]

Might not be looked at favourably by some.
However not by the Regs or any knowledgeable sparks.

 

[haptism]

where does your swa start on stop eg starts at your house/where the fcu is and ends at the shed?

No the SWA dont start at the house FCU, it starts at an adaptable box under the patio. Dont know why I didn't install it, but i see what you mean

 

[haptism]

Might not be looked at favourably by some.
However not by the Regs or any knowledgeable sparks.

Thats what i thought aswell ! Just checking

 

[Corbs]

No the SWA dont start at the house FCU, it starts at an adaptable box under the patio. Dont know why I didn't install it, but i see what you mean

if it was me i would be looking into getting it change (you might not like that) because unless he has applied some gel and maintenance free connectors, water could get in and corrode / short thing out bad practice if you ask me

 

[haptism]

if it was me i would be looking into getting it change (you might not like that) because unless he has applied some gel and maintenance free connectors, water could get in and corrode / short thing out bad practice if you ask me

Its concreted in

 

[Corbs]

Its concreted in

lol :mad2: if there is a joint under there very bad practice then as access is required

 

[haptism]

lol :mad2: if there is a joint under there very bad practice then as access is required

Yes, all for the sake of an extra meter or 2 of swa.

 

[Deleted member 26818]

Might be that a resin filled joint has been used, or some other type of maintenance free joint?

 

[Corbs]

Might be that a resin filled joint has been used, or some other type of maintenance free joint?

and the only way your going to find out is either phone the spark or start digging unless its on the test sheets

 

[Deleted member 26818]

Just wondering how the OP knows there is an adaptable box under the patio?

 

[davesparks]

To update, ive found that exporting the TN-S is not looked at favourably; so does the SWA need to be earthed via the TT.

I think if you managed to export TNS anyone looking at it would be very impressed! How on earth you can sell an earthing system to another country is beyond me!

However if you were talking about extending an existing TNS earthing system and equipotential zone to include an outbuilding then there is no problem at all so long as you do it properly with respect to the requirements for bonding.
If there are extraneous conductive parts in the shed then there would have to be a main bond of the appropriate size for the intake position (normally 10 mm for a domestic supply)

If you did need to create a TT earth for the shed then the SWA would not be connected to this, it would need to be isolated from the TT earth and connected to the TNS. The bonding and cpcs in the shed would connect back to the MET of the TT system.

 

[ian.settle1]

Just wondering how the OP knows there is an adaptable box under the patio?

Because that is where the house owner put then realised they didn't know what they where doing.

 

[Deleted member 9648]

Cant believe this nonsense still comes up,I suppose TNS makes a minor change from TNCS though.

 

[Prat P]

Its concreted in

you have just found a nice little job as all joints must be accessible so you might as well rip it out and run in armoured cable into the house,or possibly install a weatherproof isolator then you will not need to rip whole of existing cable out. Simply run new armoured cable from supply side of isolator into property.

 

[haptism]

Thanks, have to have a word about this one. Customer wont like having patio dug up thou.:biggrin:

 

[Corbs]

Thanks, have to have a word about this one. Customer wont like having patio dug up thou.:biggrin:

hold on so you arnt the customer ??????????? you doing an ecir by an chance?

 

[haptism]

No im not the customer, its a friends house and he wants me to check it out visually. I told him it looks OK, but was not sure about the earthing (although from what i gather here the tn-s earth is OK to use).

The crack is he wants a new CU and all the certificates for his house and dont want any surprises about the shed when he gets around to finding someone to do the job. I told him I cant do it immediately because I dont have a meter, and maybe he would be better off getting someone part P. Im just checking it for any obvious f ups which could be re mediated before-hand. From the sound of it its just the inaccessible armoured connection (is that a regulation that all joints have to be accessible, or is just a matter of good practice) ?

Cheers

 

[davesparks]

So you're not an electrician then?

He's better off getting someone fully qualified and ignoring all claims about 'being par p'
Especially considering that part p has nothing to do with carrying out a condition report.

 

[trev]

To update, ive found that exporting the TN-S is not looked at favourably.

Please explain why.

 

[Corbs]

Please explain why.

his last post explains everything lol diyer

 

[haptism]

his last post explains everything lol diyer

Whats it matter if im a diyer or not, im not doing the job, im trying to learn something

 

[markc123]

From what you have described, no.

Well here's a blast from the past.

Good too see you returning to this forum!

 

[Guest55]

Well here's a blast from the past.

Good too see you returning to this forum!

Quiet fool , you'll scare him off.

;-)

 

[markc123]

Quiet fool , you'll scare him off.

;-)

If only it would work for you.

 

[Corbs]

Whats it matter if im a diyer or not, im not doing the job, im trying to learn something

"No im not the customer, its a friends house and he wants me to check it out visually. I told him it looks OK, but was not sure about the earthing (although from what i gather here the tn-s earth is OK to use).

The crack is he wants a new CU and all the certificates for his house and dont want any surprises about the shed when he gets around to finding someone to do the job. I told him I cant do it immediately because I dont have a meter, and maybe he would be better off getting someone part P. Im just checking it for any obvious f ups which could be re mediated before-hand. From the sound of it its just the inaccessible armoured connection (is that a regulation that all joints have to be accessible, or is just a matter of good practice) ?

Cheers"

you shouldnt be looking at it at all not even for advice if your not in the know

 

[Knobhead]

Thanks, have to have a word about this one. Customer wont like having patio dug up thou.:biggrin:

No im not the customer, its a friends house and he wants me to check it out visually. I told him it looks OK, but was not sure about the earthing (although from what i gather here the tn-s earth is OK to use).

The crack is he wants a new CU and all the certificates for his house and dont want any surprises about the shed when he gets around to finding someone to do the job. I told him I cant do it immediately because I dont have a meter, and maybe he would be better off getting someone part P. Im just checking it for any obvious f ups which could be re mediated before-hand. From the sound of it its just the inaccessible armoured connection (is that a regulation that all joints have to be accessible, or is just a matter of good practice) ?

Cheers

Whats it matter if im a diyer or not, im not doing the job, im trying to learn something

Keep going........

 

[haptism]

Please explain why.

Started another thread on that just now, thanks for the input anyway

 

[haptism]

you shouldnt be looking at it at all not even for advice if your not in the know[/QUOTE]

No, why not, who are you anyways. Is there a law saying i cant look at things

 

[Engineer54]

No, why not, who are you anyways. Is there a law saying i cant look at things

More to the point, who the hell are You, to be dishing out electrical advice on a subject you clearly don't have a Scooby Doo about?? Are you one of these failed electrical trainee's that fell by the wayside or what??

 

[Corbs]

Thanks, have to have a word about this one. Customer wont like having patio dug up thou.:biggrin:

No im not the customer, its a friends house and he wants me to check it out visually. I told him it looks OK, but was not sure about the earthing (although from what i gather here the tn-s earth is OK to use).

The crack is he wants a new CU and all the certificates for his house and dont want any surprises about the shed when he gets around to finding someone to do the job. I told him I cant do it immediately because I dont have a meter, and maybe he would be better off getting someone part P. Im just checking it for any obvious f ups which could be re mediated before-hand. From the sound of it its just the inaccessible armoured connection (is that a regulation that all joints have to be accessible, or is just a matter of good practice) ?

Cheers

i dont know anyone that call mates/friends customers, so come on lay all your cards on the table and tell the truth you installed the power/ supply to the shed and now your unsure of the earth procedure

 

[Deleted member 26818]

Don't really think it matters whoever the OP is DIY or whatever.
He asked a question, I don't see why it can't be answered.

 

[haptism]

Don't really think it matters whoever the OP is DIY or whatever.
He asked a question, I don't see why it can't be answered.

Yes, thanks for highlighting the point.

 

[haptism]

More to the point, who the hell are You, to be dishing out electrical advice on a subject you clearly don't have a Scooby Doo about?? Are you one of these failed electrical trainee's that fell by the wayside or what??

For a start pal, im not dishing out advice im asking for it; and to add that im qualified with 2360 pt's 1 & 2 and have 12 + years experience in commercial.

 

[haptism]

i dont know anyone that call mates/friends customers, so come on lay all your cards on the table and tell the truth you installed the power/ supply to the shed and now your unsure of the earth procedure

Deleted

 

[DPG]

you have just found a nice little job as all joints must be accessible so you might as well rip it out and run in armoured cable into the house,or possibly install a weatherproof isolator then you will not need to rip whole of existing cable out. Simply run new armoured cable from supply side of isolator into property.

Out of interest do you rip out and redo all hidden joints you come across? Daz

 

[Engineer54]

For a start pal, im not dishing out advice im asking for it; and to add that im qualified with 2360 pt's 1 & 2 and have 12 + years experience in commercial.

Well you've certainly fooled Me then!! lol!!

 

[Prat P]

Out of interest do you rip out and redo all hidden joints you come across? Daz

If I'm getting paid to do so yes I do..why wouldn't I?

 

[Geordie Spark]

For a start pal, im not dishing out advice im asking for it; and to add that im qualified with 2360 pt's 1 & 2 and have 12 + years experience in commercial.

Then surely a little domestic job like this should be a breeze for you.

I'm confused. :confused5:

 

[haptism]

Then surely a little domestic job like this should be a breeze for you.

I'm confused. :confused5:

Yeah im just double checking, Ive always worked for others who have sorted that side of it. Just keeping myself interested mate.

 

[tazz]

Haptism...can you kindly update your profile to show your experience, otherwise you leave yourself wide open.

 

[Geordie Spark]

Yeah im just double checking, Ive always worked for others who have sorted that side of it. Just keeping myself interested mate.

Good lad!!

It's very dangerous stuff this electricery if you don't know what you're doing with it so it's better to safe than sorry.

They're all good lads on here who will all do their best to keep you safe & sound and it's not true what you may have heard about Our Tony ... he's not really a grumpy old git - it's just a little act he puts on and he's as good as gold really..

 

[haptism]

Haptism...can you kindly update your profile to show your experience, otherwise you leave yourself wide open.

Sorted

 

[haptism]

Good lad!!

It's very dangerous stuff this electricery if you don't know what you're doing with it so it's better to safe than sorry.

They're all good lads on here who will all do their best to keep you safe & sound and it's not true what you may have heard about Our Tony ... he's not really a grumpy old git - it's just a little act he puts on and he's as good as gold really..

Great, its a good resource this website !

 

[Deleted member 26818]

Hah, I never list my Quals or experience, like to keep em guessing.