A photovoltaic module test chamber tests a PV module for fatigue and other stress failures that appear when temperature changes repeatedly. Module service life is roughly twenty to thirty years, and the chamber reproduces the design of an onshore solar photovoltaic module made to operate for more than twenty years under ordinary climate conditions. The relevant tests are thermal cycling, humidity freeze and damp heat.
Thermal cycling
The test runs in a chamber space with an air velocity above 2 m/s, cycling between −40°C and +85°C, with heating and cooling rates below 100°C per hour. At specified temperatures the module is held stable for 10 minutes, and each cycle is shorter than 6 hours.
Humidity freeze
At room temperature the module is placed in the chamber and tilted more than 5°, then the door is closed and 10 cycles are completed. The low and high temperatures must stay within 2°C of their set values.
Damp heat
Again at room temperature, the module is placed in the chamber and tilted more than 5°; the door is closed and the test is run under severe conditions, at a temperature of about 85°C for 1,000 hours.
Operate the chamber to the specified requirements to get accurate results, and keep up routine maintenance.