Testing
Preview
The Hot Spot Endurance Test (HSP) evaluates the ability of photovoltaic (PV) modules to withstand reverse-bias hot spot heating without compromising safety or reliability.
A Hot Spot occurs when the operating current of a module exceeds the reduced short-circuit current of a shaded,
damaged, or mismatched cell. The affected cell is forced into reverse bias, dissipating electrical power as heat. In conventional modules, depending on environmental conditions, hot spot temperatures may reach 130–150 °C or higher. Module design and material selection strongly influence the resulting impact.
Prolonged hot spots may lead to: encapsulant discolouration, solder bond fatigue or melting, metallization corrosion, backsheet damage, glass cracking, bypass diode failure and increased fire risk under extreme conditions (particularly if a bypass diode fails in open-circuit).
