Patent ID: 6872936

Claim:
An accelerated weathering apparatus, comprising: an enclosure having at least one door for access to a test chamber defined within the enclosure; a specimen mounting apparatus disposed within the test chamber for supporting specimen holders; a light source disposed within the test chamber for producing light in the test chamber; a power source for powering the light source; a test module removably disposed in a pocket defined in the at least one door for detecting irradiance in the test chamber produced by the light source and generating an irradiance signal representative of the detected irradiance; a ballast connected to the light source for controlling the amount of power received by the light source from the power source; a controller connected to the test module and the ballast which controls operation of the ballast by transmitting a ballast control signal, whereby the controller adjusts the ballast control signal in response to the irradiance signal received from the test module in order to maintain a desired irradiance within the test chamber; and a calibration module for detecting the irradiance in the test chamber in order to generate and display a reference value which represents the detected irradiance, whereby the calibration module interchangeably replaces the test module in the pocket to detect the irradiance in the test chamber and display the reference value on the calibration module which is inputted to the controller for adjusting the ballast control signal.