HPAC (high voltage safety) testing
Hi-pot or flash is a safety isolation test and is applied to isolation transformers to ensure that the isolation between the windings does not break down. This guarantees the integrity of safety critical insulation in accordance with international standards. Where transformer provide isolation between dangerous line voltages and safe low level voltages is HPAC a critical test.
Tests are operated between windings and between windings and the core material.
FIGURE 8 (Hi-pot AC test circuit).