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sub panel problem

swvega

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Jun 1, 2007
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84
Location
princeton mn
I've run wire to sub panel in new shop now have a problem. I put 4-0, 4-0, 2-0, alum. wire with a #6 covered copper for a ground in 2" plastic pipe 24" in the ground.shop is about 200' from house. I got 200' of wire and had about 5' left when cut to fit at panels. Problem wire is to big to fit into 100amp main in shop panel and to big to fit into 100 amp breaker at house panel. What is the best way to fix this.
 
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Aceman

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Jan 28, 2007
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Location
Eastern Oregon
I've run wire to sub panel in new shop now have a problem. I put 4-0, 4-0, 2-0, alum. wire with a #6 covered copper for a ground in 2" plastic pipe 24" in the ground.shop is about 200' from house. I got 200' of wire and had about 5' left when cut to fit at panels. Problem wire is to big to fit into 100amp main in shop panel and to big to fit into 100 amp breaker at house panel. What is the best way to fix this.

Google Polaris Connectors or Burndy Insulated Taps. You'll have to go to a supply house to get them. Splice on a short piece of #3 Cu or #1 Al to fit the smaller panel lugs.
 

Nealcrenshaw

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Mar 20, 2008
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Location
Cleveland,OH
Right, you have to splice or weld a smaller wire to fit into the lugs.
The voltage drop shouldn't be a problem because it's only a small length .Keep the smaller wire under 6 inches.
 

Charles (in GA)

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Jan 11, 2006
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50 mi south of Atlanta
Some panels have optional parts. Look in the inside the door placard. It may list larger lugs to use with the larger wires. You could order them thru a supplier of that brand panel.

Charles
 

IDASHO

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Moscow, Idaho
This is one reason I ran copper. I had much less of a run though (45 ft), so the cost difference was much less.

4/0 copper fits right into a 125A breaker.
 
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W-Cummins

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Jan 9, 2006
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Iowa
This is one reason I ran copper.

4/0 copper fits right into a 125A breaker.


As would 4/0 Al, also fit, right into any breaker that 4/0 Cu will fit. The conductors are the SAME size....

William...
 
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franksinatra

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Nov 26, 2006
Messages
169
Location
Minnesota
I just ran 1awg aluminum I think. lol The casing says 1awg anyway. The wires are too big to fit in the neutral and ground bars so I needed to purchase a lug conversion kit. They screw onto the normal bars and accept bigger wires. As you can tell Im not an electrician but someone I know is. lol

I have a Square D system too so I dont know if that will help you or not. G
 

IDASHO

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Moscow, Idaho
As would 4/0 Al, also fit, right into any breaker that 4/0 Cu will fit. The conductors are the SAME size....

William...

Nowhere did I say they were not.

But running copper allowed the connection without anything fancy.

A similarly rated aluminum conductor would be a different story.
 

rinny_tin_tin

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Dec 20, 2008
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636
Location
Northern Virginia
If you put a smaller conductor in series with a larger conductor, than the max ampacity for that circuit is the ampacity for the smaller - thus the upstream circuit breaker should be sized to protect the smaller conductor. Generally, if you can't fit a conductor in a lug, you have a size mismatch and you likely need a bigger panel. 4/0 copper conductor is rated for 195 to 260 A (depending on type and temp rise) Although a 200 feet run may be valid concern for voltage drop, I think you can use much smaller conductors. It was probably a b*tch pulling all those fat conductors through 200+ feet of 2-inch :)

Does your local code allow 2/0 alum neutral with 4/0 pole conductors?
 

GSSFC

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Apr 13, 2008
Messages
423
Location
Wolfeboro, NH
Wouldn't pulling back a strand or two (enough to make it fit into the breaker or lug) accomplish the same thing as installing a smaller wire without introducing another splice or joint? You could even cut that extra strand or two so you wouldn't have to worry about stray conductors??

Tim
 
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