Cable size for 30m run

[regedit]

Will be run in pcv conduit below ground from MCB to an outbuilding.

I was thinking 2.5mm will be enough to power a couple of sockets (for light power tools) and lights.

If I want to future proof for potential additional small aircon unit (< 9,000 BTU) do I need to use 4mm ?

Thanks. 

[Crossy]

Ok, let's assume you will load up your outlet / lighting to 10A or so (some of my tools are pretty Ampy).

 

Baby aircon 900W = 4A (double it for start current).

 

From Doncaster Cables calculator http://www.doncastercables.com/technical-help/ you could just do it on 2.5mm² (5% drop) but going up to 4mm² is probably wise if the budget allows.

 

Are you going underground or aerial?

 

[Sophon]

56 minutes ago, Crossy said:

Ok, let's assume you will load up your outlet / lighting to 10A or so (some of my tools are pretty Ampy).

 

Baby aircon 900W = 4A (double it for start current).

 

From Doncaster Cables calculator http://www.doncastercables.com/technical-help/ you could just do it on 2.5mm² (5% drop) but going up to 4mm² is probably wise if the budget allows.

 

Are you going underground or aerial?

 

From the OP:

Quote

Will be run in pcv conduit below ground from MCB to an outbuilding.

Sophon

[Crossy]

@Sophon that will teach me to speed-read posts ????

 

Anyway, for underground runs, even in conduit our OP will be looking at NYY cable (smaller sizes are available). 

http://www.bangkokcable.com/product/backoffice/file_upload/131007_34-450!750V 70C NYY-2C.pdf

 

NYY can actually be buried direct thus saving the cost of putting in a conduit.

 

Money could be saved by running 2-core and providing a local ground rod at the shed (RCD protection needed).

 

[regedit]

Thanks for the replies !