My electric Flipsky outboard cutting at 42A - anyone knows why or what to try?

[NauticalTechTinkerer]

Hi

I’m on this crazy project trying first to build an outboard and then adding foils to my rubber boat. I want it to fly

But anyways, I’ve built the outboard with a Flipskys 85165 and a FS350A motor controller at 72v (I will reduce that to 48v for safety).

On our first sea trials I had limited it to 30A to see that nothing breaks. Worked great. So I upped the motor current to top 120 and now it cuts power whenever I reach 42A. I suspect the parallel lines going way too out of voltage, but… It’s a huge 20S21P pack with tons of copper and Nickel… So it seems strange. It’s really not that much for this big battery pack after all. I got a 150A Daly BMS on it.

I also remember connecting the computer (it was a few weeks ago and a Malaysia vacation came in the way) … And the computer game me some error saying IMU wizard or something similar. Sadly I seem to have lost the image of the screen

Has anyone else had similar issues or the motor just suddenly cutting power? I’m using ADC as throttle if that helps anything?

I posted a video where it happens in the beginning. I’m a little lost here so any help would be greatly appreciated! I can’t really imagine another forum with more Flipsky experience so I hope you don’t mind!

Video with it failing early in the video: https://youtu.be/cQ8MTjSi5zo?si=Jp8aJ92CdvDPvhXe

Cheers

[Strongarm]

Post some screen shots of your settings. Most likely the absolute current is being reached by a spike in current.

Increase Abs_current and enable slow_abs_current to true.

[Toto44]

what are your settings for low voltage recognizion?

[sharrow]

I already succesfully build an electric outboard with 70165 from hobiba and the fsesc 75350 from flipsky. I can send you my motor config if you want. Maybe that helps. To find the correct settings it was a lot of trial and error. The motor now got 9,3kw with standard propeller. Only thing left to solve is the problem with sucking air because of too much power.

Play with these settings and try again.

[Strongarm]

Could you put a plate above the motor to help with the air sucking in?

[sharrow]

Thank you, this is what I already did. But maybe its not big enough. It ended up where the propeller ends and it is in diameter the same like the prop. Next step is to make it bigger. Also think about a second plate above the other one.

[Toto44]

i am running an outboard too with 85165 Motor and 75350. After motorrecognition wizzard and some adjustemnts in max current and voltage recognizion it run fine.

[sharrow]

Looks really cool, how do you stear it.

[sharrow]

Don’t you got problems with sucking air?

[Toto44]

Teleflex steering

[Toto44]

until now I draw up to 5500W, until then no problem with air. Maybe you need to put it deeper in the water

[sharrow]

Yes 5500w is no problem but I got 9300w and the air problem comes after 5500w

[sharrow]

How is the steering attached to the motor? Couldn’t see on the pictures.

[Toto44]

which Prop are you using? we have the same motor and controller, what KV does your motor have? Mine reaches 75C quite fast if more than 5500W. I can go higher for short periods, to see if cavitation will be a problem

[sharrow]

I got a 70165 with standard propeller for more static thrust and also flite prop and 120kv

[Toto44]

On this lever going under the deck

[sharrow]

75C You mean the motor temp or the controller?

[Toto44]

Motortemperature. Contoller barely goes over 40

[Jezza]

Is the motor sitting in the hull slipstream or ‘under’ the hull slipstream?

[sharrow]

I tried different hights and its under the hull the best. The higher I come the worser it gets.