Residential service voltage drop

[nizak]

Recently looked at a job that’s going to be a new residential build.

Customer last year built a garage and had a 320A service with 2 200 disconnects set at the structure.

Now is building a new home that’s approximately 350-400’ feet away from the garage.

I would already have almost 4% VD just to the new house panel without any branch circuity added in to the equation.

Wire size above what I’d need to get that 4% number lower puts me with conductors that are too big for the disconnect and load center lugs.

Reducing the conductor size at both end terminations would be a PITA.

Live with the 4% and call it good?

Suggestions appreciated.

 

[electrofelon]

Depending on specifics, I often would use 350MCM for that length, and that will terminate in a lot of 200 amp equipment. If you bump up to something like 500, it's really not a big deal to transition at the ends with some of those in-line mechanical splices.

 

[electrofelon]

IHI - P500 500 kcmil Aluminum Splicer-Reducer

Buy 500 kcmil splicer reducer lug with hex socket screws. Allows 500 kcmil to 6 AWG copper or aluminum wire, and is UL recognized. Aluminum with tin plating. IHI Connectors brand. Made in the USA from domestic and imported parts

lugsdirect.com

 

[nizak]

Thanks much..

 

[nizak]

Depending on specifics, I often would use 350MCM for that length, and that will terminate in a lot of 200 amp equipment. If you bump up to something like 500, it's really not a big deal to transition at the ends with some of those in-line mechanical splices.

Lugs in equipment are labeled #6- 300 mcm

 

[electrofelon]

One other idea, particularly if this is a bigger fancier house, maybe sell them on a true panel board. Much nicer all around, and you could order it with exactly the lugs you would need.

 

[electrofelon]

Lugs in equipment are labeled #6- 300 mcm

350 compact will fit. Although technically not legit if the lug doesn't differentiate between compact and regular stranding. Don't ask don't tell