Am wanting to connect a 5k gas generator to a transfer box at the panel, but the generator needs to be located in a shed about 60 feet away. Its the typical 30a 120/240 lead, and I know I could run a 10g wire to carry the current, but I’m concerned about voltage drop over that distance.
Question is: Do I need to spring for the 8g wire ($2/ft) or can I get by w/ the 100′ roll of 10/3 I have on hand ? (it’d be pulled through underground conduit–60ft or so–from the shed to the panel)
Replies
P -
It depends on the load you're going to attach to the generator. The more amps drawn the greater the voltage drop. If the shed is 60' away, then how long will the actual circuit-wire be? More than 60, right?
The formulas to calculate voltage drop are pretty straightforward.
But if you want a simple answer, more copper is probably better. You only cry once..........
Hope you're pulling UF cable. Regular romex isn't rated for wet use, and inside an underground pipe is going to be a wet location. Unless you live in a desert.
Ed
EDit: for clarity. I hope.
Edited 6/2/2007 3:38 pm ET by edlee
Ya know, I was thinking about this aspect: 5 KW doesn't really translate into a whole lot of amps.................5000/240 = 20.8.
I was thinking around 30a. The #10 is probably good.
Ed
for that distance you will only lose about 5 volts ,
which is < 2%, so the #10 will be fine.....until you buy a bigger generator.
but 5Kw is not a lot of power if you plan on runnning anything that has a motor in it !
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, wer ist jetzt der Idiot ?
Thanks for the replies..that's about what I was thinking. I don't think I'll ever need anything more than the 5kw unit I have--it's only for powering emergency stuff like a well pump, fridge and lights. Think I'll save my money and stick w/ the 10g wire.
pinko, you may need this for future reference- Starting and Full-load Running Wattage Required for Single Phase Electric Motors
Motor Horsepower
Watts Required........To Start ..............To Run
1/4 .... 1000............ .............215
1/4 .... 1500 ...................300
1/3 .... 2000 ........................400
1/2 .... 2300 ...................575
3/4 .... 3345 ........................835
1 ........ 4000 .................1000
1.5 .... 6000 ........................1500
2 ....... 8000...................2000
3 ........ 12,000 .....................3000
6 ....... 18,000 ................4500
7.5.... 28,000 ......................7000
10 ..... 36,000 ...............9000.
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., wer ist jetzt der Idiot ?
Here's two quotes from this thread: "But if you want a simple answer, more copper is probably better. You only cry once..........", and "it's only for powering emergency stuff like a well pump, fridge and lights."I'm thinking you may want more power in the not-so-distant future. I'd lay the heavier wire as a "just in case".Brooks
Better try out the generator first. I have had Generac 5KW generators that would not power a 10 gpm submersible well pump and anything else at the same time, like furnace blower, freezer, etc.Frank DuVal