ESC32 Q&A

[JussiH]

Post any questions about ESC32 in this thread.

[jhoexp]

Hi,
what's the max pwm frequency input and resolution for this ESC32?

Why the 2 rows of fets on both side of pcb? This way is more difficult to use an heatsink and find a good place for the esc.
Have you considered a more conventional layout and format, maybe longer but thinner, to fit better on smaller frames or on multirotors arms?

Anyway, nice product! Any latency comparison with other escs?

[JussiH]

[LPR]

Bill
The octo I have that the AQ autopilot will go on has motors designed to 6s lipo batteries. After testing the motors with different batteries and props I find that 6s a123 batteries with 12" props instead of 10" props gives me the thrust I need for a successful octocopter.

The question is, do you think or know if it is safe to use the 6s A123 battery instead of 5s lipo?
The voltage for a 6s A123 is 19.8 and a 5s lipo is 18.5volts.

6 years ago I found out the hard way that too high a voltage can cause major damage. I used 5s A123 with a MK FC many times with no problem but when I connected a brand new A123 pack with a fresh charge I fried the board.

The maximum voltage on A123s is 3.6V for 21.6v. Lipos maximum voltage is 4.2V x 5 for 21volts.
So maximum voltage is only .6 Volts higher.

Larry

[bn999]

If you are asking about ESC32, the max voltage the FET drivers are rated at is 20v. 5S can be as high as 21v for a short period of time. The DS of the FET drivers allows a little wiggle room, but we are already pushing it.

[LPR]

[LPR]

I have 8 ESC32 wired in my octo and I'm using 5s lipos. All the ESCs are working but I'm looking for a better way to power the ESCs fets and the MCU. I power the ESC32s MCU with a UBEC and I know it will b e hard to always remember to connect the UBEC first and when the main power supply and then to reverse the process when disconnecting the power.
Does anyone see a simple solution?

Larry

[Kisssys]

Hi Larry,

If you look on the FC board, each motor output positive pin has a small solder jumper that is not completed. If you complete that jumper you can power the ESC's from the FC board instead of your BEC.

The board makes some power adjustments for change in battery voltage, if you feed the FC board a regulated voltage it will not be able to correctly do that. I think you will need to make some code changes if it's not fed a normal Lipo battery. You could drop the voltage to the FC through 6 silicon diodes and then change the battery detection to follow the A123 battery profile applying a offset for the voltage dropped across the diodes. The AQ takes considerable effort to get running and your adding variables that no one has had experience with.

Good Luck
Steve

[LPR]

Steve

I think the diodes will work.
I ordered the AQ board but Jussi will not be back till August so it will be a few more weeks till I have one.
A123 batteries have a very flat voltage output and often have a small voltage increase near the end of there charge.
For my project the A123 are a very necessary complication.
I have 5s lipos that I can use for calibration and test flying.

The voltage regulator on the FC is OK with 5s lipos right?
Should I use a few diodes to bring the voltage down for 5s lipos also?

Larry

[Kisssys]

Hi Larry,

Well a full Lipo is 4.23 volts that times 5 is 21.15 volts so your above the Recom regulators max input rating of 18 volts.
The voltage rating may be more towards power dissipation so it might work as long as the load on the 5 volts stays low. I personally would drop the Lipo voltage also just to make sure.

Their are other regulators of the same format that handle a higher voltage so if 5 cells becomes an issue maybe the board can use different regulators in the future.

Cheers
Steve