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View Full Version : What size alluminum wire do I need to carry 100 amps for 300'max 220 v


TONYTTT
Feb 23, 2010, 08:47 AM
220 volt max , mostly 110 a compressor , welder , tools , lights ,typical hobby garagel 350' panel to panel (from house to garage)

tkrussell
Feb 23, 2010, 08:52 AM
Need to know actual voltage. If you located in USA, then the voltage is 240 volts, not 220.

You title mentions 300 feet, then your post mentions 350 feet, which is it.

Need load in amps and/or watts for compressor, welder, lights.

Or you can go here:

Southwire - Delivers Power (http://www.southwire.com/ProductCatalog/voltdrop.jsp)

And do you own sizing of the feeder.

TONYTTT
Feb 23, 2010, 09:12 AM
Sorry new to this site , 350 ' in Ohio , and would like 100 amps back at the barn, need to know alluminum wire size and copper wire size so I can shop for wire

KISS
Feb 23, 2010, 09:21 AM
350' might be a bit long and you may have to go step up/step down transformer. Not sure.

Can you give a breakdown of the loads expected? Are the 120 V loads expected to be nearly balanced in the panel? Any motor loads?

KISS
Feb 23, 2010, 09:36 AM
<threads merged>

Use "Answer this question" to reply to thread. Don't start a new one.

TONYTTT
Feb 23, 2010, 09:45 AM
Thank you ! 110 mostly , welder is 220/30amps , used once in a while ,110 grinder 110 furnace blower motor , 4 high output fluorescent lights , basic home garage

johnmprince
Feb 23, 2010, 05:39 PM
1/0 alum @ 100 amps @ 350' has a 5% voltage drop.

tkrussell
Feb 23, 2010, 05:42 PM
John, can you please show how you arrived at #1/0 Al ?

johnmprince
Feb 23, 2010, 07:11 PM
By pushing the wrong buttons . Right answer 3/0. Usually helps to push the right buttons! Sorry about that.

tkrussell
Feb 24, 2010, 05:37 AM
Somehow I arrive at #2/0, based on the variables you listed.

In any case, to answer this question, using readily available products, and allow for other unknowns, I woul recommend using #4/0 4 wire URD cable.

This is overkill, but I feel the best as this cable is widely used, readily available, inexpensive, and will give good performance.

Sure, smaller wire may work, due to lower loads, but I fell the best.

Special attention will be needed at both termination ends due to wire will not fit in panel and breaker lugs.

If Tony considers this cable, then we can help with how to connect at that point.

350 feet is a long way to deliver 120 and 240 volt power and be sure to allow all equipment to run properly and not be damaged by low voltage..

KISS
Feb 24, 2010, 06:54 PM
Somehow I arrived at 4/0 Aluminum not being overkill. At 350 ft and 100 A non-continuous and 240 V, I arrive at 2.9% or a 7V drop.

And, your actually good for a 50 A unbalanced load which can mean 50 A drawn from one leg and none from the other.

240 loads mean no neutral current is needed.

In the US residential distribution is 240/120. 220/110 has been long gone.