NEW BUILD INSTALL HELP !!!

[mikep]

This is the first new build and would like a bit of advice

Got a new build, a very small single floor bungalow, living room, bedroom, lounge, kitchen bathroom, heated flooring 3 x 2.2 Kw units, 1 x electric heated Megaflow, plus cooker & oven to wire up but have not worked on a new build yet, DNO ( EDF ) are supplying a PME SP&N 100amp supply and have asked for a brick cupboard at the boudary to house head & meter in, the bungalow is 10 metres to the Consumer unit from the head.

Would like to know start to finish what they will want and how best to run it.

1. Want to bury it so what depth 450mm ?, what do I cover it with just cable cover and warning tape.

2. Could I use 25mm or better to go larger for this, remembering the 10 metre run to CU.

3. Do I just leave it sticking up through the meter cupboard base and they connect armour etc at their end or at my end, best way to terminate SWA at CU eg gland it and metal or plastic CU.

4. Do I carry out all dead tests and calculate with the enquired figures to issue Cert for them to see.

As I say never done one before help would be fantastic, are their any photo

 

[Andy™]

1. Want to bury it so what depth 450mm ?, what do I cover it with just cable cover and warning tape.

450mm will be fine. tape 150mm above it

2. Could I use 25mm or better to go larger for this, remembering the 10 metre run to CU.25mm would probably be OK, but you could always install it in a duct for future changes

3. Do I just leave it sticking up through the meter cupboard base and they connect armour etc at their end or at my end, best way to terminate SWA at CU eg gland it and metal or plastic CU.

you will need to terminate it into a switch fuse to protect SWA, leave tails from this ready for them to connect to meter

4. Do I carry out all dead tests and calculate with the enquired figures to issue Cert for them to see.

all you can do is dead tests

my red

 

[NozSpark]

Will they not put the head and meter in/on the house???

 

[ProDave]

Before you commit to anything, talk to them about a "building site supply"

This is the normal procedure up here (Scottish & Southern Energy):

You pay the cost of having a supply provided including an extra

 

[mikep]

Andy, when you say a switched fuse what do you mean exactly, surely the Head fuse does that !!

Noz, apparently they have said they will only just put it past the boundary from the pavement, seems mad to me and they are not connecting into the street feed they are running it up the road 150 feet to the high street.

 

[mikep]

Thing is prodave the bungalow is being built in the garden of the house he owns already so he has started work etc and uses the external socket on this property for the cement mixer so don't need site power, I'm just doing the install.

keep the comments coming boy's

 

[mikep]

Photo's anyone !!!

 

[Evans Electric]

The last thing they will do is gland off your armoured sub main. they will fit meter and 100 amp DP switch and scuttle pff to the warmth of their van.

You need to fit a metalclad 100 A isolator , gland your SWA into it and meter tails to their switch or meter. Their 100A fuse will protect your cable which could be 25mm X 3 core. certainly no bigger !! Meter enclosure must be built big enough for your switch gear too.

They will not be interested in your test results. They will make live but meter will be fitted when customer has chosen a supplier so the builder needs to push for that.

Your final tests when juice is on.

If you fit a metal 80A switch fuse a 16mm X 3 core could be laid in the ground .

Just to recap, the DNO are not interested in anything after the meter , so gland SWA into metal sw/fuse and 25mm meter tails and 16mm G/Y connected to their switch.

You'll have to look up the recommended depth for the cable , I saw reference to 600mm the other day ,sanded and taped . Get the builder to lay a duct then pull it in towards the end. Most builders are twiglets and put the digger through it half a dozen times if you go too early.

Deke

 

[Evans Electric]

Can I predict your next question will be How do I connect the SWA to a plastic consumer unit ?

 

[Andy™]

Andy, when you say a switched fuse what do you mean exactly, surely the Head fuse does that !!Noz, apparently they have said they will only just put it past the boundary from the pavement, seems mad to me and they are not connecting into the street feed they are running it up the road 150 feet to the high street.

the service head fuse is only to protect their cable. 7671 takes over after that, and so cables must be protected. but DNO will allow use of their fuse to protect tails, providing its upto 3mtr (less in some area's)

and there may not be capacity in the 'street feed', and the closest place is the high street

 

[Badger]

Can I predict your next question will be How do I connect the SWA to a plastic consumer unit ?

drill hole as suitable size iunto body of c/u and gland off, unless not any were to drill round hole then use a pvc adaptable box butted up to c/u and gland off via the adaptable box

:coffee

 

[mikep]

So to get this right 25mm tails, 16mm Grn/yellow into a 100amp fused isolator 25mm 3 core SWA armour glanded to isolator case 3rd core to Earth ( seperate run Earth ) run at 450mm/ 600mm depth with warning tape 150mm above SWA into bungalow with plastic CU, terminate Armour in case only, two lines to L+N on CU, 3rd core to MET.

Did I get that right or missed something.

 

[ianmacd]

Earth Armour at cut out end too.

 

[mikep]

I thought you only earthed on end on this setup, must me confused with something else.

 

[sparkytim]

Hi

I think we may have a misunderstading here about what EDF thinks and what YOU REALLY NEED.

It sounds like they are providing a TBS (Builders Tempory Supply) which is only provided to just inside Boundary of site.

This is not what you need by the sound of it.

You will end up paying twice.

Suggest if you do not need power to work from for build then ask for NEW SUPPLY TO Finished build.

All you need to do is provide Flush Meter box in wall and trench to boundary then EDF will bring THEIR cable up to Meter box.

This saves cost of Sub Main etc.

 

[ianmacd]

I thought you only earthed on end on this setup, must me confused with something else.

On any SWA run the armour should be earthed at the supply end and potentially at the other end depending on if you are exporting the earth or not (but should be in a nylon gland if not).

 

[ProDave]

Thing is prodave the bungalow is being built in the garden of the house he owns already so he has started work etc and uses the external socket on this property for the cement mixer so don't need site power, I'm just doing the install. keep the comments coming boy's

So why all this messing about with a brick built box on the boundary for the supply head and the meter?

Build the new bungalow, Incorporate a duct in the foundations for the supply cable to be fed through, and when the new property is watertight, they just feed the supply through the duct into the house and have the head, meter and CU all together as normal.

I just don't understand why they want you do go down the route of this brick built enclosure for the meter? I thought that was just your way of getting a supply on site before the new house was built.

 

[mikep]

I was just told that they are going to run it this way, don't know why will question it.

I think I will go over it with the customer to make it clear what they have ordered up, it seem's to me that it does require a run into the house to simplify it, I have seen a house locally which has a shared alley down the side, the owner of the house has had 3 dwellings built in the garden and has exactly the same setup brick built lockable cupboard for supply in his front garden at the boundary then supplies runs down the side of original property feeding the new dwellings.

 

[ProDave]

It sounds like the DNO is trying to get away with the minimum work, but don't just accept this, it just sounds wrong to me.

YOU are responsible for digging trenches etc on your land. The DNO are only responsible for digging trenches and laying cable up to your ground.

So usually the customer digs the trench and lays a duct under the foundations so the DNO don't have to do any "work" on your land.

Perhaps you have not made clear to them that you can or will do that, or perhaps even someone said you will not do that, which might be why they are proposing this rather strange arrangement.

 

[mikep]

I will try and find out more but am sure EDF want it done this way but may be a site supply.

Thanks all,