PID susceptibility lab test

The PID susceptibility lab test checks how sensitive a module is to Potential Induced Degradation (PID) by putting a high voltage on the shorted module leads while the outer surfaces of the module are grounded. In the chamber method the module is held at about 60°C and 85% relative humidity for 96 hours under its rated system voltage and polarity, and the humidity itself provides the path to ground. Another method grounds the module face with a conductive electrode such as metal foil, typically at 25°C for 168 hours. This method skips frame features like edge clips or rear rails that would slow PID in the field. Power is measured before and after the stress. A module that loses more than 5% fails, and modules that failed the 60°C test also degraded from PID outdoors. Testing for polarization-type PID (PID-p) calls for UV illumination through a transparent electrode. In bifacial PERC modules the loss shows up much more strongly when the rear side is flash tested. Leakage current can be logged during the test to check that it is stable, but it is a weak indicator of how much the module has degraded. Limits: the test has not been shown to match field behavior for SHJ modules, chamber temperature and humidity must be kept uniform, and long tests at 85°C can set off other degradation mechanisms.

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• sentence 4: support check: partial - The >5% fail criterion and outdoor failure of modules failing the 60°C test are stated, but measuring power before and after stress is not explicitly stated.
• sentence 7: support check: partial - SHJ relationship unexplored, chamber uniformity issue, and 85°C extended tests causing other degradation are stated, but the 85°C caveat is about extended tests in damp heat with bias and uniformity is an 'issue needing attention'; broadly matches. -->