Aluminum cable sizing

[ThaidaGwaii]

I have to run cables from the utility pole all the way to my house.  I tried the calculators online and I'm getting different answers.

 

I'm not sure if I will go single phase or 3 phase yet.  What I do know is the cables are aluminum, and the distance is 150 meters.

 

1% or 3% voltage drop ???  Your opinion?

Single phase, 3 phase?  Your opinion?

 

so...  Here's the possible scenarios:

 

> Single phase 30 AMPS

 

> 3 phase 10A (30A)

 

> 3 phase 30A (90A)

 

Thanks for the help!

P.

 

 

 

[Crossy]

It's not clear exactly what supply PEA are offering so I'll do the numbers for the common sizes 5/15, 15/45 and 30/100. The sizing would be the same whether single or 3-phase.

 

For 150m of Al, :-

 

5/15 (calculated at 20A) - 25mm²

 

15/45 (calculated at 50A) - 50mm²

 

30/100 (calculated at 100A) - 95mm²

 

These are done at 5% drop on full load, you may want to go one size larger if you have big water pumps or the like which take large starting currents.

 

Also you may need to splice a short pigtail of copper to the bigger Al in order to get it into the meter and your main breaker (don't just trim off strands), I would make the splice outside your home and only run copper inside.

 

Discuss with your electrical contractor and PEA before buying anything, aluminium cable is relatively cheap, but it's not that cheap :)

 

This is the stuff you should be looking at http://www.bangkokcable.com/product/backoffice/file_upload/140522_750V70C_THW-A_LV.pdf