20A Breaker & NOT #12 or 10

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Alwayslearningelec

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If there was a few light poles that were being feed from a 20a breaker several undred feet away and based on voltage drop calculation you need #6 or 8 wire why would they have a 20a breaker. I though that is you had a 20a breaker pretty much no matter what it would be #12 or #10 wire. I know wire sizes and how many amos they are good for based on conditions etc. but have you ran #6 or #8 wire to a 20a breaker?

The scenerio is (3) 20a circuits being fed from 500' away on a 120v circuit.
 
Ponchik

Ponchik

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I have never done one but how do you terminate larger than 10awg on a 20Amp breaker.

and dont say cut off the strands. :D
 
roger

roger

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edward said:
I have never done one but how do you terminate larger than 10awg on a 20Amp breaker.

and dont say cut off the strands. :D
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You splice a smaller (properly rated ) conductor to the larger conductor.

Roger
 
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Strathead

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horsegoer said:
Could my calculations/calculator be right when it says a 120v 20A circuit gogin 400 feet needs a #2AWG????
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I disagree with Roger and say no. I come up with #6, but you have to specify much more than a 20A circuit to actually do voltage drop calculations. First, is it a single load at the end of the 400 feet? Also, what is the actual load? VD does not need to be based on the total circuit ampacity, but that actual known load on the circuit. So, my assumptions in the above question are, that it is a single load 400 feet away, maximum current is 16 amps, because it is a lighting load and you are subject to the continuous load rule for overcurrent protection. In PVC conduit the VD for #6 is 2.87% I come up with #4 at 2.28% for a full 20 amps.
 
roger

roger

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Strathead said:
I disagree with Roger and say no. I come up with #6, but you have to specify much more than a 20A circuit to actually do voltage drop calculations. First, is it a single load at the end of the 400 feet? Also, what is the actual load? VD does not need to be based on the total circuit ampacity, but that actual known load on the circuit. So, my assumptions in the above question are, that it is a single load 400 feet away, maximum current is 16 amps, because it is a lighting load and you are subject to the continuous load rule for overcurrent protection. In PVC conduit the VD for #6 is 2.87% I come up with #4 at 2.28% for a full 20 amps.
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And unless the calculator assumed all the same things you assume the calculator could very well come up with a #2 AWG depending on what info it was given. I did not try to imagine a scenario or do a calculation to come up with a hypothetical answer, I just stated yes.

Roger
 
Joethemechanic

Joethemechanic

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horsegoer said:
The scenerio is (3) 20a circuits being fed from 500' away on a 120v circuit.
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Personally I think it is not very economical to use 120 volts to power something 500' away. Way too much money in wire in order to keep voltage drop and I^2R losses down.

Why are you stuck on using 120?

Can't you use 240 or 208 or whatever you got there?
 
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iwire

iwire

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How can we agree to using a higher voltage without having a clue what the specifics of the installation are?

Obviously using higher voltages makes great sense in many cases, other times it does not.
 
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