Day Ahead Instrumentation, LLC, is a value added reseller (VAR) of the Rotating Shadowband Radiometer (RSR2TM) for Irradiance, Inc. of Lincoln, Massachusetts. The RSR2TM measures global horizontal irradiance and calculates diffuse horizontal and direct normal irradiance. The most common commercial application relates to designing, monitoring and testing solar power plants that convert solar radiation into electricity. The RSR2TM irradiance sensors come from LI-COR Environmental, whose primary business is measurements for agriculture. RSR2TM data loggers come from Campbell Scientific, the world leader in highly accurate, rugged, low-power remote sensing devices.