Strong MAG interferences

I made Advanced Compass Seteup and got 76% of max interferences (throttle 75%, max current 52 amps). Too hight for me. I have external compass secured od cca 10 cm high “mast” (see photos). My battery is secured horizontally. Does it help make longer mast and/or secure battery verticaly? Any other idea how to decrease interferences pls?

Is it a Li-Ion battery? Those require more distance from the compass. Did you follow the Magfit procedure?

Yes, 6s2p Li-Ion 10 ah battery. I didnt make magfit procesure yet. First i want to decrease interferences and after that do magfit calibration

Magfit accomplishes that. That battery will be a problem.Even 2 different batteries if the same capacity and construction can produce different offsets. Or if the battery is not fixed in the same spot each time. Taller mast.

Thank you. Do you mean this procedure?

Yes. Fly a couple figure eights (to produce varying yaw) with some throttle changes. Using the MAVExplorer is the easiest route.

How long shoul be the mast? Now it is 10 cm tall

There is no definitive answer to that. After running Magfit are you getting compass errors?

Does anyone have experience with COMPASS_LEARN?

I don’t think anyone has used that since Magfit has been available. If anyone actually used it prior to that…

Why would a Li-Ion pack require more distance, given equal lead length? TU! I’ve never seen that stated anywhere.

I have seen it stated many times on the forum here (search li-ion interference here) and have experienced it myself on the same craft using both Li-ion and Lipo’s. Li-ion are cans of metal… On small craft it can be terrible. The above mentioned one is a sub250g that started out with a 2S Li-Ion the same battery I use in a Plane. The flight time was only surpassed by the compass variance error messages. It has a 3S Lipo now.

Dave, thanks! I’ve never run Li-Ion as a flight battery - my bad for not paying attention. Makes perfect sense.

… for most vehicles I don’t think the log based magfit is required. The easier 3D compass calibration should be good enough.

If you do choose to go the extra step of using the logs then the web based log fit tool is recommended.

Just a follow up of our discussion how important is battery orientation and mast lenght and that is good idea to trade off increase of drag resulted from vertical battery placement for reduced magnetic interferences