I probably set the motor at max power and continued at max power above the water which likely caused the issue.
This is likely a consequence of inexperience. Pointing the board upwards is probably sufficient. I am experimenting. There’s very little information available on foil-assist techniques for those who don’t know how to foil yet
Ye, battery was full. No BMS, just fuse.
I doubt it’s an overheating issue for several reasons:
The previous session was completely fine.
The slowdown only began after a few startups and ollies, with rest periods in between.
The ESC always feels cold to the touch (unlike the battery). Active cooling is a very effective type of cooling.
Slow down is caused by low voltage limit or temperature (lots of users set it to 90 degrees). If you’re battery is weak, you’ll see by the bargraph flashing on your Remote when you take off.
Cut off is caused by current limit protection reached. Generally set to 60 amp for the heavier riders. It’s a good " battery saver"
The experience was definitely similar to when the battery runs out of power. It’s likely that the ESC detected a pulse voltage sag and switched into a low-power mode as a precaution.
However, there are additional settings whose functions I’m not familiar with.
Static tested today XCross 160A.
Just put the foil with the board on sand in shallow water. (Don’t do it - it filled the motor and prop with sand).
Flipsky remote L/M/H setting
Measured battery current with a clump meter at max throttle. Interesting results:
H - 150A-170A
M - 75A
L - 25A
In my setup (transparent larger than usual ABS box) I cool esc with small fans and small heatsinks.
Measured heatsink temperature with a thermocouple and inside closed box temperature with some gadget.
Environment temperature 22c
Inside box temperature reached max 35c.
Always max throttle.
H - Fans or no fans - lasted 10-20s till protection kicked it - depending on the starting temperature. The heatsink temperature rised in about 10s till 50c+.
M - Lasted much longer, but eventually protection kicked in, depending on the starting temperature - it can be 1m, or 10s.
L - could run all day long without triggering protection.
Fans kept the heatsink temperature at max 50c+.
Test without fans on L+M:
L 60s, then M 10-20s and again. After 5-6 cycles heatsink temperature risen till 65c and then M could not do 20s.
Temperature protection works such that soon after limiting, the ESC frees throttle again.
Conclusions:
Seems like current max throttle at H is too much current.
Fans keep the temperature lower, but usually 55c which suggest that larger heatsinks and fans will do better.
Given sufficient current no heatsink will cope with such large amount of heat generated, because of the way these mosfets are cooled.
For continuous operation (no falls, no waves, no pumping) with intermittent starts these heatsinks inside without fans are not enough.
My explanation why adding only one side large external heatsink helps overall - it makes the ESC PCB cooler thus less heat left for the other inside heatsink.
Next to try:
Foiling full session on M without fans still with these heatsinks.
This is really interesting. I have been using the 160a esc but did have problems. I have a couple spare unused and would use them again if I could be confident with them.
How are you setting L/M/H? Is this in the flipsky remote or in the blheli software? I have only used the Maytech remote so not familiar.
Ye, I am not sure as well about these figures, the clump showed it steadily. It is pretty good clump that I have used for low amps. I zeroed it beforehand.
Yes, it is very high current and power. I didn’t measure the voltage, it was hard with the waves there, but maybe I will do another session.
3p p42a molicel should handle such a current I guess… The fuse is 200A
Have you been using it since? Anything that I won’t be able to do compared to BLHeli? I have been told the voltage limitation is not available?!
Thinking about getting the SEQURE 12200 with am32.
Cheers mate
I don’t have this ESC anymore, unfortunately I can’t see the differences. I think there was no throttle calibration option. Now I use Flycolor FlyDragon 150A ESC, so I have absolutely no problems with control programs )))
I have a SEQURE 12200 with new firmware running BlHeli32, which the Chinese sent me. It works very well in the air and needs to be tested in water, but it’s already very cold here.
