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Data acquisition checklist PV thermography

Data acquisition checklist PV thermography

📋 How to use this checklist: Work through each section in order — Before flight day, Flight day conditions, then After flight. Tick each box as you go. If you have questions, your Volateq contact is happy to help.

⚠️ Important: Volateq can only begin the process below after receiving a purchasing confirmation (Signed Sales Order or Purchase Order). Upon receipt, we will schedule a short pilot briefing call to walk through this checklist together and make sure everything is ready for takeoff.

✏️ Before flight day

Confirm with your Volateq contact that the flight routes are ready for your site. Experienced customers can set up their own flight routes: How to create your own flight routes
Check your RTK (Real-Time Kinematic positioning) service. RTK is strongly recommended (though not mandatory) for precise flight routes and high-quality data. Without RTK, insufficient GPS accuracy may cause defects in the resulting orthomosaics (stitched aerial image maps). More info: VolaFly App: RTK and NTRIP setup
Install the VolaFly Drone App on your drone controller (recommended). Installation instructions: Volafly App: Download and installation for DJI drones (except Mavic 2)
Verify you have a fast enough SD card. Recommended models: SanDisk Extreme 128GB V30 microSDXC or SanDisk Extreme Pro 128GB V30 microSDXC

☀️ Flight day — Conditions and preparations

Weather conditions

Wind speed below 5 m/s
Less than 10% of the sky covered by clouds. If a cloud casts shadow on part of the solar field during flight, pause and resume 10–15 minutes after the cloud has passed
Clear and sunny conditions, with irradiance (Plane of Array / POA) > 650 W/m². POA irradiance measures how much sunlight hits the solar panels directly — this threshold ensures results are reliable

Plant condition

Solar field is in full operation — no clipping in any part of the area being flown. All non-operational modules will appear as "open circuit" in the results
Area of interest is operating at close to nominal power
Solar field is clean — cleanliness > 0.97 (i.e. less than 3% soiling losses). If soiling analysis is booked in parallel, higher soiling levels can be tolerated
No row shadowing from adjacent rows during flight — especially important in winter when sun angles are low

Tracking PV fields only

The items below apply only if your solar field uses tracking systems (panels that follow the sun throughout the day). Skip this section for fixed-tilt installations.

Complete all flights within a window of no more than 2 hours before and after solar noon
During data acquisition, ensure all module tilt angles are below 30°. Results may be compromised for trackers in off-tracking positions. For soiling flights, tracking considerations differ — see: Data acquisition checklist PV Soiling
If you manually override the tracking algorithm for the flight, always ensure POA irradiance remains above 650 W/m²
If trackers are operational and not set to angle-zero: ensure the entire area of interest can be completed within the same day, within the flight window. Do not split flight areas across multiple days as weather conditions will vary and compromise data consistency

Soiling analysis

If soiling analysis is included, refer to the additional task checklist for flight day: Data acquisition checklist PV Soiling

🚁 Drone setup and launch

Best Practice: Before launching de routes on Volafly enter DJI Pilots Health Management system and verify the status of all components.

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Safety Pre-Check
Start the drone only at the designated starting point of your flight routes (waypoint "0"). VolaFly will show a warning if this is not met — do not ignore it
Configure drone settings according to the app you are using:
VolaFly Drone App: How to launch with VolaFly
DJI Flight Hub 2 / DJI Pilot 2: DJI Pilot 2 configuration guide — then launch using the KMZ flight files exported from our WebApp
Start with a full drone battery
Do not touch any controller wheel or button during flight — this may accidentally change camera settings and render the flight data unusable
Watch the camera livestream on the controller screen and check for sun reflexes or unclear image quality. If reflexes appear centrally in the image, counter-act by adjusting the tilt angle of tracking PV systems, or wait until the reflex weakens
If solar plant conditions change by more than 10% during flight (e.g. cloud passage, tracker malfunction, curtailment): pause image acquisition (return to home) and resume after 10–15 minutes once conditions are back to normal

Best Practice: Use a landing pad. It protects your drone from dust during takeoff and landing. Most DJI drones (including Enterprise models) feature Precision Landing: after takeoff, the drone captures a reference image of the ground using its downward camera at around 6–8 meters of altitude. When returning to home, it uses that image to land more accurately on the original takeoff spot. A high-contrast landing pad helps the sensors acquire the landing point more reliably.

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Example

🔬 Additional requirements for IEC 62446-3 compliant inspections

For inspections carried out according to IEC 62446-3, the following sensor data must be recorded during the drone flight:

Sensor

Minimum requirement

Notes

Sensor

Minimum requirement

Notes

Irradiance (POA)

Pyranometer or calibrated reference cell in plane of array

Must be logged with timestamp; required to verify >600 W/m² during flight

Ambient temperature

Calibrated sensor in shade, near the array

Required for temperature-corrected module ΔT calculations

Wind speed

Anemometer at hub height or array level

Must remain below 5 m/s; gusts invalidate results

Module temperature (optional but recommended)

Contact thermometer or reference module with PT100 sensor

Supports emissivity correction (adjustment for how efficiently a surface radiates heat)

Logging requirements:

  • All sensor data must be timestamped and logged at minimum 1-minute intervals during the flight window

  • Data must be uploaded alongside drone imagery to the Volateq analysis

⚠️ Without the sensor data above, the analysis can still be performed as a high-resolution inspection — but the result will not be IEC 62446-3 compliant.

📤 After flight — Data upload

Upload your data (raw videos and metadata files — not as a .zip archive) via the VolaFly Drone App or Volateq's WebApp: Volafly App: Flight mission execution and data upload
Once the upload finishes, use the "Show coverage" tool in the data upload window to verify completeness. Drone positions should cover the solar field in a regular pattern (see screenshots below)
Once coverage is confirmed, tick the "Data complete" checkbox (see screenshot below). This notifies the Volateq team to begin evaluation of your analysis

The screenshots below show how to use the coverage check tool, an example of a partial upload (north-eastern sections not yet covered), and how to mark an upload as complete.

📚 Further reading