100 amp sub feed

[nizak]

Does anyone else find it difficult when it comes to feeding a 100 amp sub panel to an outbuilding from a dwelling service panel?

By the time I travel 60' or so thru the basement of the dwelling, then another 100 or so feet outside, I end up with a conductor size that is difficult to both fit in the house panel and terminate on the neutral bar.

If it's aluminum, it's even worse.

 

[Cow]

I like 90 amp subs. Then I can use #2 AL with a #4 neutral and #6 ground. Sizes I know will fit existing ground and neutral bar holes.

 

[petersonra]

Does anyone else find it difficult when it comes to feeding a 100 amp sub panel to an outbuilding from a dwelling service panel?

By the time I travel 60' or so thru the basement of the dwelling, then another 100 or so feet outside, I end up with a conductor size that is difficult to both fit in the house panel and terminate on the neutral bar.

If it's aluminum, it's even worse.

What difference does how far the conductor goes make?

 

[electrofelon]

Does anyone else find it difficult when it comes to feeding a 100 amp sub panel to an outbuilding from a dwelling service panel?

By the time I travel 60' or so thru the basement of the dwelling, then another 100 or so feet outside, I end up with a conductor size that is difficult to both fit in the house panel and terminate on the neutral bar.

If it's aluminum, it's even worse.

Most of the time for these situations, the phrase "voltage drop" will not even enter my brain (I am assuming upsizing for VD is what you are getting at?).

 

[kwired]

If VD is a concern, run your #3 copper or #1 aluminum through the house and into your supply panel, hit a junction box on exterior of house and increase size there to continue to the outbuilding. At the outbuilding a 150 or 200 amp main breaker panel is likely less cost then an additional junction box and reducing to 100 amp conductor again, so what if it is only supplied with a 100 amp feeder breaker.

 

[ActionDave]

I like 90 amp subs. Then I can use #2 AL with a #4 neutral and #6 ground. Sizes I know will fit existing ground and neutral bar holes.

:thumbsup: I do this for out buildings all the time. Back in the day we would use 100A breakers until one of our inspectors started making us use 90A.