Neutral VD

[ptonsparky]

Resistive loads only for this purpose.

I want to calculate the VD on the reduced neutral of a feeder to a remote panel. Imbalance current of 12 amp. #6 cu Hots, #8 cu neutral. Avg of 21375 cm. L1 = 25 amp, L2 = 37 amp, N = 8.

I used 120v and 8 amps with a distance of 100' to come up with 1.21% VD or 1.448 volts.
What am I missing? Seems like I should be taking into the consideration the L-L VD.

 

[LarryFine]

L1 = 25 amp, L2 = 37 amp, N = 8.

No. 37a minus 25a equals 12a as you said, not 8a.

Seems like I should be taking into the consideration the L-L VD.

No. L-L current has no bearing on neutral current.

 

[ptonsparky]

No. 37a minus 25a equals 12a as you said, not 8a.


No. L-L current has no bearing on neutral current.

Yes, I grabbed the 8 from the wrong column when typing and never even... Brain Fart. Old age. HUA syndrome, etc. Pick & choose.

 

[winnie]

You just use the neutral current to calculate the neutral voltage drop.

You use the line current to calculate the line (hot) voltage drop.

The load voltage drop is the combination of line and neutral drop.

Remember that for one leg ( in a single phase center tap system ) the load will experience a voltage _increase_ from the neutral voltage 'drop'.