Bypass Diode

IEC TS 62916:2017(E) describes a discrete component bypass diode electrostatic discharge (ESD) immunity test and data analysis method. The test method described subjects a bypass diode to a progressive ESD stress test and the analysis method provides a means for analyzing and extrapolating the resulting failures using the two-parameter Weibull distribution function. It is the object of this document to establish a common and reproducible test method for determining diode surge voltage tolerance consistent with an ESD event during the manufacturing, packaging, transportation or installation processes of PV modules.

IEC 62979:2017 provides a method for evaluating whether a bypass diode as mounted in the module is susceptible to thermal runaway or if there is sufficient cooling for it to survive the transition from forward bias operation to reverse bias operation without overheating. This test methodology is particularly suited for testing of Schottky barrier diodes, which have the characteristic of increasing leakage current as a function of reverse bias voltage at high temperature, making them more susceptible to thermal runaway.