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voltage drop question, residential

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S

Stevenfyeager

Senior Member
Location
United States, Indiana
Occupation
electrical contractor
Most of my jobs requiring wire sizing due to voltage drop are a single cable going to a single load, such as a distant sub panel. My workers asked me about a lighting branch circuit in a very large house. Should we add all the lengths of NM cables on that circuit and if it totals say 150 - 200' or more, do we need to calculate the voltage drop like we do for single runs ? The lighting load is spread out, not like at the very end of a single run. Any advice ? Thank you.
 
LarryFine

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
For a rough idea, use half of the total circuit length.

If there's a lot of these, install a sub-panel.
 
M

menoknow

Member
Location
Washington State
Occupation
Electrician
You have to treat each branch individually and do the voltage drop calc for it. Depending how it's wired I would probably just upsize the home run. You're just trying to find how much resistance is between the source and the load.
 
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