Holiday tester voltage

[pipex60]

Hi,
I am looking for the correct voltage to be applied to check painting of pipe - 350 microns, polyurathane paint.

Thanks

 

[gr2vessels]

Try to read ASTM D5162. Here is an excerpt from the standard:

"The low voltage wet sponge test equipment is generally used for determining the existence of discontinuities in coating films having a total thickness of 0.5 mm (20 mil) or less. High voltage spark test equipment is generally used for determining the existences of discontinuities in coating films having a total thickness of greater than 0.5 mm (20 mil).
Coatings that are applied at a thickness of less than 0.5 mm (20 mil) may be susceptible to damage if tested with high voltage spark testing equipment. Consult the coating manufacturer for proper test equipment and inspection voltages".
Cheers,
gr2vessels