AC vs. DC dielectric withstand testing: Allowing AC or DC testing in 61010-1 3rd edition

Abstract

The IEC 61010-1 3rd Edition standard for measurement and control equipment for laboratory use prohibits DC hipot testing on circuits energized by AC voltage. Originally, the 2nd edition of the standard allowed for both. With this change, there have been some unintended consequences for test houses and manufacturers. Often times, the AC hipot test causes false failures due to the capacitance of input and EMI filters. Furthermore, various studies have shown that the DC equivalent to an AC hipot test is acceptable for testing the quality of solid insulation. This calls into question the removal of allowing an equivalent DC hipot test for an AC hipot test.