Service point in out building

[Frisky182]

Hi there.
My friend is building a new house. He has decided to put service point in and out building next to new house. A duct has been run from out building to house. I will be using 16mm three core to supply house db. I've decided to use rcbo's for circuits in the house. But I am unsure if the cable at the out building side should be rcd after the cut off to supply the house? Any advice would be appreciated.

 

[Andy78]

Are you an electrician or is this a DIY job ?

 

[Rockingit]

Two things:

1) Check your calculations for voltage drop for the lighting - you might need to upgrade that 16mm to a 25mm depending on length of run
2) It would probably pay you to bring the incomer into a metal-clad consumer unit anyway as that way you have something to make your armoured off to and also can run some ancillary sockets and lights in the outhouse more easily.

No, you don't need to provide upstream RCD protection to the cable, but personally I would install it onto a DP MCB rather than a single.

 

[HandySparks]

What is the earthing arrangement for this new installation?

 

[ChrisElectrical88]

Lengh of run and more info required please? As said by the post above a metal clad board would be best. If your using RCBO's i would go for Schneider, good price and very good board.

 

[Frisky182]

It's a 20m run. And a TN-S system. It a three bedroom 1 and half storey house.

 

[Frisky182]

Thanks for reply. It's a 20m run. In a one and half storey three bed house.

 

[Octopus]

and no answer if its a DIY or sparky doing it.........so its another DIY job

 

[telectrix]

1 and 1/2 storeys? must be DIY as he's already demolished half the upstairs. :drool5:

 

[ian.settle1]

1 and 1/2 storeys? must be DIY as he's already demolished half the upstairs. :drool5:

Or it's already half sunk into the ground

 

[GLENNSPARK]

come on frisky....own up..

 

[Frisky182]

The half storey is built in the roof space with dormers!!!

 

[Frisky182]

No it not DIY. I'm just asking for some advice as I'm not long qualified and just needed some advice. Thanks for the actual genuine advice on this.

 

[GLENNSPARK]

go for an armoured sub....

this does not need RCD...
then RCD for finals (in this outbuilding)...

think RCDs in series..

 

[Guest55]

The half storey is built in the roof space with dormers!!!

sounds like some sort of hobbit hole..........




what the hell are you building over there ? lol.

;-)

 

[ferg]

1 1/2 storey houses are the norm here.
I live in one

 

[Guest55]

1 1/2 storey houses are the norm here.
I live in one

i hope youre saving up to buy the remaining 1/2 storey like a normal house ?

B-)

 

[ferg]

It's taken me fifty years of saving to get out of the shoe box in the middle of the road.

 

[DPG]

MP: Shoe box?
TG: Aye.
MP: You were lucky. We lived for three months in a brown paper bag in a septic tank. We used to have to get up at six o'clock in the morning, clean the bag, eat a crust of stale bread, go to work down mill for fourteen hours a day week in-week out. When we got home, out Dad would thrash us to sleep with his belt!
GC: Luxury. We used to have to get out of the lake at three o'clock in the morning, clean the lake, eat a handful of hot gravel, go to work at the mill every day for tuppence a month, come home, and Dad would beat us around the head and neck with a broken bottle, if we were LUCKY!

 

[ian.settle1]

go for an armoured sub....

I thought they all where armoured with torpedos

 

[londonfire]

I would use 2 core 25mm swa and a separate 16mm earth. Terminated in a metal clad box (or plastic with 32mm knockouts) feed it from a 100A main switch there to an adaptable box (again with 32mm knockouts. And then supply your board as normal with meter tails from the adaptable box.

Or use 3 core swa and leave one core a bit longer so it will go from the earth at source (tns) to a met at the db. Would look something like this in the end.

 

[Rockingit]

As it's TN-S you don't need to do ^^^. The Cu Equiv. of the armour should more than meet your adiabatic.

 

[Octopus]

I would use 2 core 25mm swa and a separate 16mm earth. Terminated in a metal clad box (or plastic with 32mm knockouts) feed it from a 100A main switch there to an adaptable box (again with 32mm knockouts. And then supply your board as normal with meter tails from the adaptable box.

Or use 3 core swa and leave one core a bit longer so it will go from the earth at source (tns) to a met at the db. Would look something like this in the end.

No overload protection for the sub main then?