Supply to outbuilding

[greener198608]

I have been given the oppurtunity to price a job which is an outbuilding. The building in question will have 8 sockets, a free standing cooker and some lighting. There are two nearby boards, one single phase and one three phase, I was wondering what cable size I would require (im thinking 16mm) and wondered what size breaker I put in the board supplying it, and what board I should use in the outbuilding. Any advice would be greatly appreciated.

 

[Ponty Massive]

Welcome to the forum

 

[telectrix]

if using 16mm cable, a 63A or , at most, 80A MCB . depends on whether you need to apply correction factors to the CCC of the 16mm. as for the board, maybe a 6way, with 3/4 RCBOs, and a couple of ways for future possible expansion

 

[greener198608]

thanks for clearing that up! What size main switch for 6 way board and do i need to provide earthing or is earth off 16mm ok

 

[telectrix]

any 100A or 80A main switch should suffice. should be no trouble using SWA 3rd core for earthing. earth the armour at both ends, and don't forget ant extraneous metalwork in the outbuilding needs to be bonded. depending on the load you may be able to use 10mm SWA ( xlpe is rated 80A at 90deg.).

 

[greener198608]

Thank you for your advice that you have given me, it has been invaluable, glad I signed up to this forum.