jordanrmoore
Member
could someone tell me what size wire i would have to run for a 200amp panel at 240 volts over a 280 foot run. thank you!
voltage drop
- Thread starter jordanrmoore
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peter d
Senior Member
- Location
- New England
Re: voltage drop
Your question cannot be answered unless we know the calculated load.
Also, are you planning to use copper or aluminum wire?
Your question cannot be answered unless we know the calculated load.
Also, are you planning to use copper or aluminum wire?
jordanrmoore
Member
Re: voltage drop
copper wire and running a 200amp panel from a main panel 240 volts.
copper wire and running a 200amp panel from a main panel 240 volts.
- Location
- New Jersey
- Occupation
- Journeyman Electrician
Re: voltage drop
Take a look here:
http://www.electrician.com/vd_calculator.html
As peter said you'll need to figure out the load.
Take a look here:
http://www.electrician.com/vd_calculator.html
As peter said you'll need to figure out the load.
Re: voltage drop
"IF" your load is a full 200 amps and this is a feeder, the NEC recommends a maximum voltage drop of 3%.
3% of 240V is 7.2V
The formula for calculating voltage drop for single phase is:
Circular Mills =2kxLxI/Vd
k=12.9 for copper @75 c
L=length
I=current
Vd=Voltage drop
You would need a conductor with a minimum of 200,667 circular mills = 4/0
For three phase subsitute 1.73 for 2 in the above formula.
"IF" your load is a full 200 amps and this is a feeder, the NEC recommends a maximum voltage drop of 3%.
3% of 240V is 7.2V
The formula for calculating voltage drop for single phase is:
Circular Mills =2kxLxI/Vd
k=12.9 for copper @75 c
L=length
I=current
Vd=Voltage drop
You would need a conductor with a minimum of 200,667 circular mills = 4/0
For three phase subsitute 1.73 for 2 in the above formula.
- Location
- Lockport, IL
- Occupation
- Semi-Retired Electrical Engineer
Re: voltage drop
A 200 amp panel will seldom have 200 amps worth of load running on it. You can certainly design it to have no more than 3% VD with a load of 200 amps. But if you do, you may end up with a larger feeder than is needed. That is a design (and economic) choice, not a code issue. But then, VD is not a code issue either.
I agree with sky1's calculation of a 4/0. But if the load were actually, let us say, 160 amps, then a 3/0 would be adequate.
A 200 amp panel will seldom have 200 amps worth of load running on it. You can certainly design it to have no more than 3% VD with a load of 200 amps. But if you do, you may end up with a larger feeder than is needed. That is a design (and economic) choice, not a code issue. But then, VD is not a code issue either.
I agree with sky1's calculation of a 4/0. But if the load were actually, let us say, 160 amps, then a 3/0 would be adequate.
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