# question on wire size in a 115V system



## icentropy (Jul 5, 2013)

Hi all I'm running a 115V 1A solar pump from 1000' away using 12g wire. I need to install a float switch at the cistern to turn off the pump when water level gets too high and one at the well to turn off pump when water level gets too low.

I can't find switches with 12g wire. would it matter if in the 1000' run there is 20' of 14g at the cistern and 20ft of 14g at the well? 

inverter----50' 12/2g ------cistern/switch 20' 14g -----1000' of 12/2 --------well/switch 20' 14g


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## Gary in ohio (May 11, 2002)

Need to go up in wire size. Your going to loose 5% of your voltage in the wire.


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## icentropy (Jul 5, 2013)

Gary in ohio said:


> Need to go up in wire size. Your going to loose 5% of your voltage in the wire.


due to the 14g switches or to the 12g wire?

based on the online calculators using 12g wire for 1000' at .93A will result in a 2.7% voltage drop. So around 116-117V at the pump.

I'm new to this so I am probably missing something?


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## JeepHammer (May 12, 2015)

1 Amp pump shouldn't be an issue.
You will build resistance with long runs of wire,
DC doesn't push through wiring nearly as well as AC does,

The standing rule is, you figure the entire run at the smallest wire gauge,
In this case, 14 Ga.
And with only a 1 Amp draw, 14 Ga. should pull it off.


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