Drone inspection

In a drone inspection, a UAV carrying an infrared, visual or other camera flies over the array along a pre-programmed path that covers the whole site. Aerial IR and visual imaging can find hot spots, bypass diode and junction box failures, cracked glass or cells, delamination, discoloration, open strings and mismatch between tracking systems. For tracker twist, a drone orthomosaic or oblique images let you compare row-end shadow lines with neighbouring rows. For terrain undulation, drone imagery helps show whether losses line up with grade breaks or motor block boundaries. For snow, it gives observations of module cover that you can line up with production residuals. Thermal flights need at least 600 W/m2 of irradiance. Wind speeds above 28 km/h can make it unsafe to control the aircraft, although the limit depends on the drone type. A drone covers a site much faster than a handheld camera: an IR survey of a 4 MWp plant takes roughly 5 to 10 hours with a drone, compared with 15 to 20 hours on foot. Not every thermal anomaly is a failure. Confirm findings against ground data such as IV tracing or EL imaging to avoid false positives. Drone EL and UV fluorescence surveys are harder because they need darkness, often night flying with a higher risk of losing the drone, and EL also requires energizing the strings. Flights must be carried out by a licensed, insured operator after a site risk assessment. Record the date, time, wind and battery levels in a flight log.

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• sentence 7: support check: partial - u20 supports EL darkness, night flying with higher risk of losing UAV control, and energizing strings, and u3 supports UVF needing dark and risking drone damage, but the higher risk of losing control is stated only for EL, not UVF. -->