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The Compass calibration is performed to allow the compass to neutralize the influence of the ferrous material on-board the aircraft. The calibration is performed at the factory and in most cases does not need to be repeated.
Preparations
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Install Mission Planner (if not previously installed)
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Assemble the copter as it would be for flight
Install batteries
Payload installation
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Some payloads affect the compass and some do not. You may calibrate without the payload installed, then install it and check the flight controller messages for errors.
If there are “compasses inconsistent” errors, then install or remove the payload and perform the calibration again
Move the copter into an open area with no metal objects nearby
Try to have at least 30 feet from any nearby metal objects
Remove any metal from the person performing the compass calibration
Watches, belts, loose change, phones, etc.
Connect batteries to power the aircraft
Use an in-line fuse if available
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