Infrared Photovoltaic System Surveys – Required Site Conditions

Required Site Conditions for Infrared Inspection of Installed Photovoltaic System

The requirements listed below are based on current industry standards, including those published by ASTM, RCI and Infraspection Institute. Compromising on any of these requirements may adversely affect the results of the Infrared Photovoltaic System Survey.

No Precipitation: No appreciable precipitation, including rain, sleet, snow or dew, should have fallen during the hour prior to the Infrared Survey. Areas that had moisture may not have enough solar loading to show the necessary thermal patterns.

Dry, Clean Solar Panels: The surface of solar panels shall be free of dew, condensation, ponded water, snow, ice, dirt, and debris. Since an infrared imager records the thermal image on the surface of the object, any areas without direct line- of-sight cannot be accurately surveyed.Infrared Photovoltaic System Surveys Required Site Conditions - photovoltaic panel

Solar Loading: Infrared inspections should be conducted on a sunny day while panels are exposed to direct sunlight. Solar panels should be inspected when solar irradiance is at least 650 Watts per square meter across the face of inspected panels. A pyranometer should be used to confirm the solar irradiance at the time of the survey.

Correct Viewing Angle: The infrared imaging system shall be maneuvered in an organized manner to ensure the complete inspection of all panels and equipment, at a viewing angle greater than 45° from the surface of inspected panels.

Winds of less than 15 mph: During of the time of the Survey, winds should be less than 15 mph.
Stronger winds can result in a cooling effect that may cause thermal images not to be seen. In addition, winds may present a safety issue if the Survey is being performed form an Elevation