First of all, a little introduction to my project. I am building a new drone with li-ion batteries to extend the flight time, I made a first prototype and after tuning the drone and performing the autotune, I tried to test the total flight time. After only about 14 minutes of hovering, one of the mosfet of the Hobbywing Xrotor Micro 60A 4 in 1 was burned and I had a crash, all the four motors stopped suddenly and the drone fell down like a rock from a high of 1.5m. Due to the low high there was no big damages, but I don’t want that this happens again.
The current consumption of the drone in hovering is about 20A, so in theory, there shouldn’t be no problem with that current and that ESC, but after contacting with Hobbywing, they told me the following: “60A 4in1 ESC is not suitable for your environment and is only used for short flights on FPV.If used over a long period of time, it may cause ESC instability and cause problems.Therefore, we do not recommend that you use it in the long usage environment you have described.We suggest you choose other XRotor products instead of FPV Racing products.”
For me, that is a bit weird but I don’t want to go against the recommendations of the manufacturer. So in that case, what mini ESC do you use? What do you think that would be the most reliable?.
So I ask you some info and experiences about using mini ESC or 4 in 1 (compatible with 6S battery) because I want that the total weight and dimensions be the low and small as possible. I had a look to the EMAX Bullet 35A 3S-6S but I don’t know if they are reliable or if there are better options.
We’ve used a Holybro tekko32 65A metal 4in1 on 4 cell lipo, 12 inch props, 910 kV motors, 2.5kg quad, 50 minutes continuous flight. And plenty of flights with solid current draw.
Manufacture specifications and application guide lines are there for a reason. You operated that ESC outside of the recommended flight parameters and it failed.
I have a set of HobbyWing X-Rotor 40A Opto ESCS in a large hex, Those ESCs are 6 years old and going strong.
FWIW, an aircraft built using shortcuts will fly all of the way to the scene of the crash.
I though when fc gives motor stop order then ESC procedure the command but there is big motor have big emf And when motor really under load and suddenly stopped so there is big emf to outputting and it’s given through esc and may-be tiny ic can’t handle it
(This is my though )
Tell me if I’m wrong or not or correct me
My Antigravity 4006 quad sports individual 35A Tekko32 F3 ESCs and works well.
Another quad, with older HengLi W4822 motors and Airbot Wraith32 50A ESCs ran into trouble twice. Specifically thermal throttling. It didn’t fell, just lost yaw authority. Due to some misalignment, the two CCW motors were running harder and their respective ESCs throttled. The quad is sipping 18A in hover and upto 30A in auto missions, depending on wind, and has flown reliably for 3 years. The thermal throttling happened only when doing some more aggressive full-throttle flying in stabilize, with 80Amp zoom-climbs.
Another important thing I forgot to mention.
Bigger motors with bigger props draw a lot more power when accelerating (ramp up power). Those current spikes can be much higher than the allowed current by the ESC. To avoid those current peaks, which may burn the esc you should reduce the ramp up power in blheli. Since I reduced it regulary to 20 (from default 50) I never burned ESC, also with longer flights. Reducing from 50 to 20 I did not see any difference in flight performance.
There is a good video from Joshua explaining it quite good: https://www.youtube.com/watch?v=wfAcMCvKZNU&list=PLwoDb7WF6c8kXOyPdBog1wtRcxnXMasUb&index=6
Thank you for that tip. I bought one tekko32 65A metal 4in1 which @xfacta recommended me, so when it arrives, I will reduce the ramp up power. I have seen that is also recommended to turn off the low rpm protection.
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