ECN Forum Forums General Topics of the Trade General Discussion Area High Voltage Voltage drop

Does any one have a link or simple formula to do Voltage Drop on 4160 And 13.8 feeders.
I can find plenty on the net for 600 volts and under. Thanks Yooper

Yoopersup,
The voltage applied is irrelevant. Voltage drop is based on the formula 2KIL/CM.
K= Specific Resistance of the material used
I= Amps
L= Length one way
CM= Circular mil area of conductor

Voltage doesn't enter into the equation. As long as you compare apples to apples IE: three phase to three phase / single phase to single phase the voltage dropped will be the same on a 208V circuit as a 12000V circuit.

I know was looking for an on line program to just input info but I all ready found it

Nick:

K= 10.4 for copper
I= amperage of load/circuit
L= conductor length (100' conduit; 2 conductors, (H-N) = 200' Length

CM= Area (Circular Mils) of conductor


Or to determine a conductor size based on a calculated voltage drop:

CM = KIL / Vd (ie: 3% of 240V = 7.2Vd)

John

3 Phase =

22.3xdistance to load in feetx amp load
---------------------------------------
Allowable voltatage drop

That well give you Cir. Mills of copper wire

22.3x distance to load in feet x amp load
-----------------------------------------
circular mill of copper wire

that well give you voltage drop


k= for example
k#1 copper at 75%C= .000154x83690=12.9
See table 8 N.E.C.


I know how to do all just wanted Comp. Program to imput numbers . I now have that program , works on all voltages )

Well then give up the program, post a link or something?