# Voltage Drop and Electrical Service Planning

 I need to run close to 250′ at 220v for 20A (or 110v for 40A, but considering the length of run and voltage drop over distance, presume to go with 220v) wire size is borderline between #6 and #8…
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Calculating Voltage Drop for Wire Size
Question: I need to run close to 250′ at 220v for 20A (or 110v for 40A, but considering the length of run and voltage drop over distance, presume to go with 220v) wire size is borderline between #6 and #8.

My question is, in the interest of economy, can I run the #6/2 or #8/2 for 125′ and then #10/2 for the second leg of 125′
(I also considered halving the amperage to 10A, and running a pair of #10/2 for the 250′ – 500′ of #10 being more economical than 250′ of #6 (or #8)
Any advise or admonition appreciated
Thanks!

This electrical question came from: Lana, a Homeowner from Monterey, CA, USA
Additional Comments: very helpful

Dave’s Reply:

Thanks for your electrical question Lana.
The Following links will assist you with your electrical question:

Electrical Calculations and Formulas

Voltage Drop Calculations
Voltage drop is an essential factor in determining the correct wire size to prevent voltage loss which will occur in long distance runs of electrical wire or cable

Electrical Calculations and Formulas

wire

Electrical Wire for the Home
Complete listing of electrical wire types and parts used for home projects with electrical code information serves as selection guidelines.

For more information about 220 Volt Wiring Diagram
220 Volt Wiring Diagram

Wiring 220 Volt Electrical Outlet
Home electrical wiring includes 110 volt outlets and 220 volt outlets and receptacles which are common place in every home. See how electrical outlets for the home are wired.

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