cable size help needed please

[taylor467]

hi everyone. thanks again for all the advice. after viewing the job this morning. it is a 200m run on a TT system. the stable s actually only having lighting and sockets. there is only going to be 3 doubles so a 16a radial will do for that. and for the lighting there are going to be 8 led floods at 8w each giving 64w in total

64w would give .28amps right?
plus the 16amp for the radial
giving me a design current of 16.28amps

is this correct?

im thinking a 25mm 2 core armoured from the house to the stables and then 25mm earth on a earth rod at the stables

could any of you tell me if im right, or close. or have i got everything wrong. i think i worked the volt drop out at 7.7a

 

[telectrix]

by using a little diversity, reduce your design current to give a VD of 3%, this will comply for the lighting.

edit: just done a quick calc. and i get a current capacity of 19.5A to give a VD of 6.9V.

 

[taylor467]

by using a little diversity, reduce your design current to give a VD of 3%, this will comply for the lighting.

edit: just done a quick calc. and i get a current capacity of 19.5A to give a VD of 6.9V.

Thanks for your reply telectrix, can you please tell me how you got 19.5. And 6.9. I also forgot to mention there will be a supply for a alarm as well, prob another 3 or 5 amp. Do you think 25mm swa would be enough, or would 35mm be better?

 

[Tiny Spark]

Dude you really need to check out a OSG or BGB.
All the answers you will ever need shall be found in there.

 

[Mr Hehound]

Think about what you have used as your lighting load then check the OSG.

 

[gaz101]

How much friction will there be pulling 200m through a pipe