Compliance Procedure
Verification of the electrical safety of a printed circuit board requires applying a voltage far exceeding the nominal operating limit to ensure the dielectric insulation holds under stress. This evaluation is performed as a high voltage isolation test, which checks both the board substrate and the spacing between conductors for dielectric breakdown. The procedure confirms that conformal coatings, solder masks, and laminate layers can withstand transient overvoltages without suffering electrical puncture.
This protocol is mandatory for assemblies deployed in industrial and automotive applications where safety is paramount.
Test Execution
Implementation of this test involves applying a high direct or alternating voltage between electrically isolated networks on the finished circuit board. The instrument monitors the leakage current flowing across the dielectric barrier over a specified duration, which is typically sixty seconds. If the current exceeds a predetermined threshold, the board is rejected for insulation deficiency.
Modern automated test fixtures integrate this step into the final test cycle before shipment to prevent high-voltage failures in the field.
Defect Detection
Identification of insufficient spacing or laminate voids is the primary output of the test. The method exposes hidden fractures within the substrate and uncovers solder splashes that bridge the gaps between high-power traces. This prevents thermal runaways during board operation.
