2007-04-27 15:20:43 · 2 answers · asked by renozlion 2 in Science & Mathematics ➔ Engineering
50 kVA ÷ .208 kV ÷ √3 = 139 amps.
You did not state whether you're using overhead or underground conductors.
A 4/c 1/0 AL overhead cable has a rating around 200 amps, so it is more than enough. Sorry, but I don't have ampacity tables handy for 4/c #2 AL or smaller conductors.
For an underground installation the cable ampacity will be affected by whether it is direct buried or in conduit.
Other factors in selecting the cable size are the distance from the transformer to the load and any motor-starting inrush.
2007-04-28 02:13:19 · answer #1 · answered by Thomas C 6 · 0⤊ 0⤋
Engineer is thinking, I will be back
1. Determine the current 50 KVA = 208 Volts * sqrt(3) * Current
2 Current = 50 * 1000/(208 * 1.73205) = 138 amps
3. I dont have a National Electric Code book at home but you can look in the NEC I know a 1/0 cable will carry this load,
you will need 3- 1/0 copper conductors. and use a #8 grounding conductor.
2007-04-27 23:48:52 · answer #2 · answered by Anonymous · 0⤊ 0⤋