In Reply to: Electrical Conductor Spacing posted by Francis LHeureux on 10/16/01 at 1:13 PM:
Typically, high voltage connectors will be rated at 10 volts per mil, or 10,000 volts per inch, of surface stress for intimate contact of the mating connector surfaces including, in some cases, with the use of insulating grease.
Taking 3500 volts at this level suggests 0.35 inch, but I wouldn't push the limit if I were you. I might suggest going to a half-inch or even one inch.
Also, consider coating or potting the board. Contact manufacturers of board coating materials and of RTV potting materials for their suggestions.
John Dunn - President