Economical voltage drop calculation experience

Status
Not open for further replies.
Rockyd

Rockyd

Senior Member
Location
Nevada
Occupation
Retired after 40 years as an electrician.
Customer wants to run a service panel 125 foot away from utility connection. Then to house about 100 more foot.
I did the math figuring 125 amp ( ""I" in the formula) and am seeing 3.13 % VD.
(VD KID/CM)

It's $ 5 a foot with 4/0 vs. $ 15 a foot for 35O Triplex.
Voltage runs about 246 to 250 volts here, (so we're a lot compared to a lot of places) thinking it should be okay (especially after seeing some other services with a lot of ground from utility to houses off the road)

Thoughts from the forum?
 
I used AL 4/0, 4/0, 2/0 triplex and came up wit 2.9% VD, which means little. You most likely will never see a 125 Amp load. Maybe if you try really hard.

Getting the 350 to fit in your 200 amp, assumed, terminals may be a real PIA.

I'm all electric about the same distance and pulled 3-4/0 Al in 2" PVC.
I never notice any lights dimming but my office UPS flags an alarm when the laser printer cycles.
 
You say 125A. Is that the expected load or the size of the breaker. For voltage drop only consider the actual expected amps running through the wire not the full capacity of the breaker seeing how you can't load a 125A breaker to more than 100A; in that case use 100A.
 
Status
Not open for further replies.
Top