WHAT SIZE WIRE?

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jwm

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I HAVE SOME LEFTOVER WIRE: MT 4/0 AWG AL XLP 6OOV TYPE USE-2. I WANT TO USE IT IN A 370 FOOT RUN BURIED BUT AM NOT SURE IF THIS SIZE WILL SUFFICE TO CARRY 200AMPS THAT FAR. IF NOT I'D LIKE TO KNOW WHAT SIZE IS NEEDED ANDIF THIS 4/0 WILL DO AS A GROUND. ADDITIONALLY, IF NOT, JUST HOW LONG A RUN CAN I USE THIS WIRE FOR AT 200 AMPS?

THANKS
 
Re: WHAT SIZE WIRE?

At 120 probably not.
At 480 probably.
What voltage?
What do you mean "ground"? Equipment grounding conductor? Grounded conductor? Grounding electrode conductor?
It will carry 200 amps for a very long ways if you are not concerned with voltage drop.
Its it really 200 amps, or is it a 200 amp panel? What is the calculated load per art 220?
Is it a service or a feeder?
 
Re: WHAT SIZE WIRE?

HI TOM:

THANKS FOR THE INPUT.

WE ARE TALKING 240 VOLT SERVICE AND A GROUNDED CONDUCTOR, 200AMP PANEL AND I AM NOT SURE WHAT THE
CALCULATED LOAD IS. THE DRAW WILL NOT EXCEED CAPACITY I AM SURE. RUNNING A WELL, AND (EVENTUALLY) A THREE BEDROOM HOME WITH AVERAGE ELECTRIC DEMAND AND GARAGE/SHOP AND POWER HAND TOOLS AND SAWS. RIGHT NOW IT IS ONLY ONE BEDROOM.

JOHN
 
Re: WHAT SIZE WIRE?

John kill the capitols OK. ;)

370' run

4/0 aluminum

240 volts

200 amp load

I come up with 6.2% or 14.8 volts "lost"

That is kind of steep.

But a 200 amp service is unlikely to draw 200 amps if we figure 80% loading, still high in my opinion given your description it will be less drop.

That would make the load 160 amps, at that load you have 4.9% voltage drop.

To keep voltage drop under 3% with 160 amps on this 4/0 you could only run about 225 feet.
 
Re: WHAT SIZE WIRE?

sorry for caps.

What would I have to run to get the full 370' with accpetable voltage loss? will the (3 phase ?) wire still fit the connections in the service box and meter?

Other solutions?

John
 
Re: WHAT SIZE WIRE?

Using Mike Holt's formula:

'Sizing Conductors to Prevent Excessive Voltage Drop' -

CM (single phase) = 2 x K x I x D/ volts dropped

Using a 3% voltage drop figure - 240 x 3% = 7.2 volts

If you use iwire's figure of 160A for the load.

K = represents a resistance constant...12.9 is number used for copper....21.2 for AL.

therefore - CM = 2 x 12.9 x 160A x 370'/7.2 = 212,133 CM....using Table 8, that is just a hair larger than 4/0 copper....I think you could fudge and use 4/0 for this situation.

If you will accept a 5% voltage drop then your conductor gets smaller (2/0 copper).
 
Re: WHAT SIZE WIRE?

JWM 4/0 for that length of a run....Wow !!!You stated average electric demand,well that`s a loaded statment.Is it an electric area or a gas area ??Region plays a big part in this North,South
Cold,Hot?? I`d say if in a mild climate area that doesnt require allot of a/c or heat and there isn`t an excessive demand it will be okay but we all know this isn`t the senario.Up size your conductors and keep the wire you have for somewhere else
 
Re: WHAT SIZE WIRE?

That is one Long piece of LEFTOVER wire!

For this run, I would probably go with 250MCM AL, it's probably less expensive than 4/0 copper.

The lugs in a 200amp meter and main breaker loadcenter should handle this.

Is there no way to do Primary, and set a padmount transformer closer?
 
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