Need to know about Surface Voltage

[Arjun Mehta]

If we apply an electrical insulating material on a bare conductor which carries 25 Kv AC Voltage. What would be the surface voltage observed on the insulating material? Is there any test/method by which surface voltage can be measured on the Insulating Material.

The Insulating material has been tested for Breakdown Voltage of > 50 Kv AC, however a specific question of Surface Voltage has been asked in this case.

Will be great if someone can help me answer this query.

Thanks a ton
Arjun

 

[anorlunda]

There are a couple of problems with the way you phrased the question.

• Surface voltage relative to what?
• 50 Kv breakdown voltage should be Kv per meter, or Kv for a specified depth of coating.

But the simplest approach is to just assume linearity. If the coating has depth D, and if the outside is grounded white the inside is 25 Kv, then draw a straight line (0 volts, 0 depth) to (25 Kv, D depth).

More specifics might get a better answer, but based on what you gave us, linearity is the simplest.