Test Procedure
Standardized test methods establish consistent protocols for assessing the durability of printed board insulation over time. Implementing ipc tm 650 2 6 3 7 defines the test procedure for surface insulation resistance of printed boards. The specific protocol measures the change in insulation resistance of a test vehicle under humid and high-temperature conditions.
Resulting measurements determine whether the board chemistry and materials are free of electrochemical degradation.
Parameter Setting
Controlled environmental chambers hold the test specimens at a constant elevated temperature and relative humidity for several days. Throughout the execution of ipc tm 650 2 6 3 7, a continuous electrical bias is applied to the interleaved conductor lines. Leakage current is measured at predefined intervals to detect any decline in dielectric properties.
If the material permits the growth of conductive dendrites, a rapid decrease in insulation resistance is recorded. This testing process ensures that cleaning residues and solder mask cure levels are sufficient to prevent field failures.
Acceptance Check
Passing values require the insulation resistance to remain above a specified threshold throughout the environmental exposure. Boards that fail to meet these limits suffer from electrochemical migration or corrosion during use. Adhering to the standard provides a clear benchmark for validating board cleanliness.
