100 amp on 1/0. 425 feet . :no:
need some help on voltage drop 425 ft
120/240v residential home, owner installed a barn and needs a sub panel installed for some water heaters/lights for the animals. The contractor that installed the barn put the PVC in for me, 1 1/2 PVC 425 feet long. I want to install a 100amp sub panel but dont know if its passable. So far the best I can figure is 1/0 aluminum, and # 6 for the ground. What do you think? Do I need to drive a ground rod?, Will this even pull, its a straight shot with one 90 and thats it. Should I put this on a 60a over current device? Copper wire is out of the question due to the cost. Also the electric fence requires two ground rods so I'm a little Leary about driving a third for the panel. Can you guys give me some ideas? Keep in mind that the 1 1/2 PVC was already installed and I need to work around it. Thanks for any help that you can give me. SO 425ft long, 100a, 1 1/2 PVC, and what to do about the grounding???
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That's what I came up with for feeder size, but what about the ground rod?
How did u come to that conclusion ?That's what I came up with for feeder size, but what about the ground rod?
I didn't do the math but my app says 250mcm copper for 3.5 percent vd , length is going to be a basterd with 1.5
1/0 alum will give ya 14 percent vd
I think, actully I know, the 6 AWG 'ground' is too small and is a code violtion.So far the best I can figure is 1/0 alumnium, and # 6 for the ground. What do you think?
250.122 requires the equipment grounding conductor to be increased in size when the other conductors are.
Likely.Do I need to drive a ground rod?,
The code requires a grounding electrode system at the building.
:blink:Also the electric fence requires two ground rods so Im a little leary about driving a third for the panel.
Leary of what?:001_huh:
First thing you have to do is decide how much current is really going to be needed.Can you guys give me some ideas? Keep in mind that the 1 1/2 pvc was allready installed and I need to wotk around it. Thanks for any help that you can give me. SO 425ft long, 100a, 1 1/2 pvc, and what to do about the grounding???
You need to know this to do a voltage drop calculation. It would be foolish to figure a full 100 amps of load if there is only going to be 40 amps of full load.
Based on what? 100 amps of load?1/0 alum will give ya 14 percent vd
Yep. I didn't do the math. The app didBased on what? 100 amps of load?
well
2xkxIxd divided by cmill = 2x21.20x100x425 divide by 105600=17.1
2xkxIxd divided by VD = 2x21.20x100x425 divide by 17.1= 105380cmill
and the cmill of 1/0 is 105600
With out derating is this ok so far?
the barn will draw 58 amps max as far as i can guess pending on what we go with for water heaters.
I'm Leary of creating an potential between three rods, thats what, also why cant I just bond the fence transformer to the rod I drive for the panel???
2xkxIxd divided by cmill = 2x21.20x100x425 divide by 105600=17.1
2xkxIxd divided by VD = 2x21.20x100x425 divide by 17.1= 105380cmill
and the cmill of 1/0 is 105600
With out derating is this ok so far?
the barn will draw 58 amps max as far as i can guess pending on what we go with for water heaters.
I'm Leary of creating an potential between three rods, thats what, also why cant I just bond the fence transformer to the rod I drive for the panel???
Load may change in time too may as well do it right the first timeI think, actully I know, the 6 AWG 'ground' is too small and is a code violtion.
250.122 requires the equipment grounding conductor to be increased in size when the other conductors are.
Likely.
The code requires a grounding electrode system at the building.
:blink:
Leary of what?:001_huh:
First thing you have to do is decide how much current is really going to be needed.
You need to know this to do a voltage drop calculation. It would be foolish to figure a full 100 amps of load if there is only going to be 40 amps of full load.
For a few dollars more the barn builder could of run 2" PVC instead.. :no::no:
It sucks these guys don't ask the guy who has to fix their mess and get it to work properly...
Running 2" is a no brainer for that length of a run....
The phone company has up running 4" conduit with large sweeps to pull in a 1/2" cable..
It sucks these guys don't ask the guy who has to fix their mess and get it to work properly...
Running 2" is a no brainer for that length of a run....
The phone company has up running 4" conduit with large sweeps to pull in a 1/2" cable..
The pipe is 1 1/2 and thats what I have to work with. I told the dude to install two 2in runs and thats not what was done.
I would run CU.. instead of AL.. now for anThe pipe is 1 1/2 and thats what I have to work with. I told the dude to install two 2in runs and thats not what was done.
from BBQ and MTW...But it is the only way I can see this working for what you need...
dig it up, or better yet have the contractor call in a direct bore specialist
He still hasn't stated a load , he said 100 amp before but I doubt he can make that work with 1.5 PVCI would run CU.. instead of AL.. now for an
But it is the only way I can see this working for what you need...
omg
Let me rephrase the question, I have a 1 1/2 PVC pipe run that is 425 ft long. The voltage is 120/240. What is the largest circuit that can be run in that pipe.
Id run it on a 2-2-4-4 URD put it on a 70 amp breaker.
Why a 70 amp breaker?:001_huh:Id run it on a 2-2-4-4 URD put it on a 70 amp breaker.
If it costs to much it might not get done at all.Load may change in time too may as well do it right the first time
If I was pricing this I might give the customer a couple of price options.
One for the known load at this time and one for a 'full 100 amps'
At this point we don't know if the customer asked for a 100 amp panel or just wants their stuff powered up.
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