Arc Length

[jbmg]

I am wondering what the mathematical formula is to calculate the length of an electric arc length in air. I can't seem to find this formula anywhere on the web. Any suggestions??

 

[dpc]

Not sure what you are looking for - the dielectric strength of air, or the maximum possible arc length?

For dry air, you can assume about 10 kV per inch for dielectric strength, but once an arc is established, it can be much longer than that.

 

[oldfieldguy]

What dpc said. 480 volts won't jump ANY appreciable gap, but after an arc is established, all bets are off as to how long the path will be and where it ends up.

old field guy