Inspection drone

An inspection drone is an unmanned aircraft that carries thermal and visible-light cameras over PV modules to record images or video. That data becomes inspection reports used to plan preventive and corrective maintenance. Its main use is aerial infrared thermography. With it you can find hot spots, activated bypass diodes, open- or short-circuited strings and offline strings without stopping the plant. Pair the thermal camera with an RGB camera. A thermal-only payload can mistake soiling, shading, bird droppings or nests for electrical faults. Fly in clear, sunny weather with at least 600 W/m2 in the module plane. Keep the IR sensor pointed straight down at the modules, and fly above five meters so the drone does not shade the modules. Wind limits vary by source and aircraft. One study recommends wind no higher than 4 m/s. O&M guidance allows up to 28 km/h for safe control, depending on the aircraft. A pre-programmed flight path keeps flights repeatable and accurate. Some lightweight cameras cannot take radiometric readings, so handheld ground thermography may be needed to measure actual temperatures. Drones can also do UV fluorescence imaging at night. This needs at least two trained people, and the extra load of the camera and UV lamp limits flight time to about 8 to 10 minutes per battery.

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• sentence 2: support check: partial - Hot spots, bypass diodes, short/open-circuited and offline strings, and no interruption of generation are supported, but 'main use is aerial infrared thermography' is not explicitly stated. -->