NICEIC Certification Scheme Advice needed on job for NICEIC assessment

[mattcos1972]

Dunno where the end of this thread has gone. I'm sure there was more conversation had last night lol!!

Right.....I have come to a decision! Flukey it looks like your advice regarding using the house earth is not only sound but expressed by quite a few people. That said I have still not been able to to find anything in the red book to substantiate or disprove it....yet!! lol!
I have a TN-S supply and there are no extraneous conductive parts in the shed. The SWA in place is 3 core 6mm and the length of the cable is not excessive (30m max). At the mo the only earth is one of the cores so I think I will also use the armour (which has never been terminated properly at either end - just shoved into both CUs)..... and terminate it at each end properly obviously.
The shed CU looks pretty sound. 63A main switch, 30mA RCD protecting 32A final ring and 6A lighting circuits. At the house end its not quite so pretty . The shed supply is dropped straight into a 20A breaker which is also being used by the radial supplying the immersion (and god only knows what else until I ripped it all out the other day.) As I am changing the CU its not an issue for now.
The new CU at the house is gonna be a split board, double RCD so I am not gonna feed the shed from it as I dont want RCDs tripping all over the place in case of a fault. So I am gonna split the meter tails in a Henley Block and feed a set of tails into a little 2 way CU in the house with a 63A main switch and just a 40A type B breaker supplying the shed. I'll then run an earthing conductor from the main earth terminal in the house to the little CU.

What do ya reckon?......I'll get my coat! lol

 

[flukey]

Dunno where the end of this thread has gone. I'm sure there was more conversation had last night lol!!

Right.....I have come to a decision! Flukey it looks like your advice regarding using the house earth is not only sound but expressed by quite a few people. That said I have still not been able to to find anything in the red book to substantiate or disprove it....yet!! lol!
I have a TN-S supply and there are no extraneous conductive parts in the shed. The SWA in place is 3 core 6mm and the length of the cable is not excessive (30m max). At the mo the only earth is one of the cores so I think I will also use the armour (which has never been terminated properly at either end - just shoved into both CUs)..... and terminate it at each end properly obviously.
The shed CU looks pretty sound. 63A main switch, 30mA RCD protecting 32A final ring and 6A lighting circuits. At the house end its not quite so pretty . The shed supply is dropped straight into a 20A breaker which is also being used by the radial supplying the immersion (and god only knows what else until I ripped it all out the other day.) As I am changing the CU its not an issue for now.
The new CU at the house is gonna be a split board, double RCD so I am not gonna feed the shed from it as I dont want RCDs tripping all over the place in case of a fault. So I am gonna split the meter tails in a Henley Block and feed a set of tails into a little 2 way CU in the house with a 63A main switch and just a 40A type B breaker supplying the shed. I'll then run an earthing conductor from the main earth terminal in the house to the little CU.

What do ya reckon?......I'll get my coat! lol

sorry mate havent had chance to look, been flat out again today.

why not install the mcb for shed before the rcd in new house cu as you already have rcd protection in the shed

 

[mattcos1972]

sorry mate havent had chance to look, been flat out again today.

why not install the mcb for shed before the rcd in new house cu as you already have rcd protection in the shed

I'm gonna do it all in the next few days anyway, chap, so I don't guess it makes too much difference. At the minute I've been inspecting bits of the current 'installation' (and I use that word very loosely lol!!) in between other jobs I am doing. Bonding, it would appear is not something that was of much concern to the original architect lol!! Although there are a few strands of aged copper attached to my water mains pipe!! lol! Also the lighting is not earthed (and my ex wife had every single fitting changed for a metal chandelier lol). As for the rest of the house, it would seem that everything else is basically a series of spurs taken off the ring final! lol! There's a 6mm cooker cable coming out of the CU but its not terminated anywhere and my cooker is electric, so GOD only knows where that goes to lol!! I tell you, Flukes, I have ripped out more obsolete wiring in the last few days than is left in the house lol!

I am gonna do a PIR on it all tomorrow, note down the dire state of it all, sort out the bonding to the gas and any supplimentary that may need doing.
Then when I put in the new CUs next week I'll put in plastic lighting fittings for now and mark the lack of earth as a category 1 fault on the 2nd PIR that I do after the job. I will be rewiring soon, but I'll wait til I'm part P as I dont have the time at the mo and my neighbour upstairs has got laminate flooring so I'll be losing a bit of ceiling for my trouble, and I just can't be arsed right now lol!!

Cheers again for all your advice mate and as soon as I find something in the regs on the shed subject I'll let you know immediately, but I am pretty convinced that you are spot on anyway.

 

[drewandsons]

Flukeys spot on ! if there are no extraneous parts etc then there is no need to fit an earth rod! If still unsure go to the I.E.E site and you will find a pdf file all about garage/shed power.

 

[mattcos1972]

Flukeys spot on ! if there are no extraneous parts etc then there is no need to fit an earth rod! If still unsure go to the I.E.E site and you will find a pdf file all about garage/shed power.

That's great. Cheers Drewandsons. I'll have a look later. I just want to be armed with something tangeable if / when the NIC ask why there's no rod out there.

Nice one guys!

Matt

 

[Jason Smith]

Morning all.

A few of you may know that I am changing / relocating a consumer unit as one of my jobs for NICEIC assessment to get Part P.
I need a bit of advice.................

I have a big shed / office out the back of my garden fed at the moment by a SWA looped into the mcb for my final ring (yeah I know.....I didn't put it in )
The problem arises at the shed end of the installation.......The shed is taking its earth from the main house cpc (literally just taken off the armour of the cable and terminated at each end). Now I know that as its a separate building it needs a separate earth to comply with 7671, so an electrode is needed to provide earthing for the shed.
My question is this? When I do the PIR, can I put in the notes that the shed is not earthed correctly, mark it as a category 1 fault, and hook it back up using the house earth as was, or do I need to make it good with an electrode, even though the work was not mine? I am asking as when I change a consumer unit does that make all the circuits "my responsibility"?

Cheers in advance

Matt

I have had this confirmed as well. I would add that it is common to use a metal garage box, must not be metal as this could be caused to be live from a fault IN THE HOUSE.The only system you join the earths together is if the house is a TT and the shed will obviously be rodded as well. a fault in the shed will also do the rcd in the housse, it will trip as well depending on where it hits it on the wave form. Delayed RCD in the house is a good idea.

 

[mattcos1972]

I have had this confirmed as well. I would add that it is common to use a metal garage box, must not be metal as this could be caused to be live from a fault IN THE HOUSE.The only system you join the earths together is if the house is a TT and the shed will obviously be rodded as well. a fault in the shed will also do the rcd in the housse, it will trip as well depending on where it hits it on the wave form. Delayed RCD in the house is a good idea.

Hi Jason,

I spoke to the NICEIC this morning about it and, to cut a long story short, they said that with a TN-S supply taking an earth from the house is no problem at all. With PME a spike should be used.

I've left the delayed RCD off at the house end, as the shed cable is being fed from a little 2 way board that I want to run a F/Freezer (non RCD) radial off of.