After closer inspection it turned out that one of the 12AWG cables from the ESC to the motor desoldered itself from the ESC. Also the other ESC-motor cable desoldered from my 6mm bullet plug which connect the ESC wire to the 10AWG wire which goes to the mast. It’s looking like a shortcut. I exactly had this scenario as the first SEAKing blew up. Last time I had water inside the pod which most likely caused the shortcut. This time there was no water inside except of condensated water on the aluminium housing. But I can’t imagine that this could be a reason.
fell your loss! It also happened to us with a seaking a few months ago. In our case it was a reverse polarity of battery current…. Stupid mistake!
the box become completely black as well ,and smelld wierd.
I had it on my eskate and I belive the motor didn’t have enough torq and drew too much amps until something blew up. The explosion was like fireworks. Literally. It only stopped when I yanked put the battery. This is why now everything gets safety features.
Or maybe just too much load on the motor.
The Seaking has neigter temp cutoff nor over current cutoff. So if your motor slows down (e.g. because of a too large prop, something blocking the prop…) but you have full duty cycle then the inducted resistance of the motor will fall, so the amps rise, this causes the mosfet temp to rise and motor heating up.
Then the weakest point of your system brakes, maybe your motor (like peter told in his outrunner tests) or the ESC or maybe even the cables or solder joints. So maybe you were drawing high amps and resoldering cables to short, or maybe just too much amps/heat till fire and then everything desoldered.
Did you check the motor (and motor temp) short after the burn?
The happened at full speed in water. It’s hard to determine if the motor got too hot because I needed to swim back to the beach for a while. It think the motor cooling is fine.
BTW, the Seaking has the temp protection:
“Overheat Protection:
when the ESC temperature goes above the factory preset value, the ESC will cut off the output and stop running, then the Green LED flashes slowly. The controller can be reoperated at the halved power after the throttle returns to zero, the output will resume if the temperature decreases below 80°C.”
Maybe my setup is drawing to much amps (700kv SSS, 8:1 neugart, 160mm prop by Hiorth, small kite board foil, small surf board)
Has anyone a good alternative for a well tested ESC on an efoil?
Have you a data logger for the current? I think that a current sensor connected to logic that sets the ESC trottle is the way to go. Even if your ESC can handle bigger current there could be another part like a connector or something else that will fail. A temp sensor on the weakest point in the ESC could be good but I think it maybe to slow to react If there is a short peak current that it can’t handle.
I’m waiting to receive mine, because datasheet of SSS motors give you a max current for each motor, I’m not aware of 700KV limits but the 360 model is rated about 95A (don’t remember exactly).
I’ve a MAXI LAMA fuse rated 100A but i don’t want’t to test it! A simple arduino buffer (if not complete receiver) that can ramp down slowly the current if you hit let’s say 100A for more than 1second, in theory could prevent similar issues.
REgarding the Flier ESC, I got that just because of the AWG 8 cables. I can’t tell how it behave under load yet, but at least cables are well sized.
I read also that firecracker effect could be due to longer battery cables…so I added 2 low ESR big capacitors in parallel near the ESC, other than route the + and - paired as much as possible.
What scares me is this desoldering thing, get to a point where the tin give up, something close to 200°C
You should send it back and ask for a new sample, because the advertisement was misleading. I did this with my YEP 120A HV as well, which is also advertised to have temperature protection (which obviously does not work), so at least i got some of my money back. The RC industry earns a lot of money with false advertisement, making their stuff not rigid enough to withstand the specified use. Most of the RC ESC do not have correct working:
Battery current limit
Motor phase current limit
Temperature protection
Cooling
and come with underdimensioned cables.
If you ask how long it can withstand the specified current the answer usually is: Until your battery is drained. If i tell them i use 32Ah and will do this for 20 minutes or longer they do not answer anymore.
The ESC cooling today consists of some thermal pads (which are always 200% better than the standard) which have absolute bad properties in any means to connect the housing of the FET to some cooling plate or water cooling. First point is the housing of the FET, the thermal resistance is usually not specified by the manufacturer and they do not want to tell how bad it is. Next point is the thermal pad which consists of some silicone rubber and needs to be really squeezed down to very thin layer. Often this is not possible due to the bad tolerances of the cheap or even manual soldering process. The mechanics inside such cheap controllers does not allow to put high pressure on the thermal pads.
The missing ability to measure the phase current leads to frequent overload of the ESC and the leads which are always underdimensioned. As powerloss is proportional to current squared (the motor phase current, not the battery current), the situation is out of control quickly, if the ESC is underdimensioned. This missing phase current limit is also likely to destroy your motor if the ESC is overdimensioned.
Is there a solution?
Maybe. If you dimension your motors load in such way, the motor cannot produce too much torque e.g. by a reduced diameter of the prop… uups, that reduces efficiency of the overall system. Yes, with a missing phase current limit, you will have to overdimension your motor and ESC to drive the chosen prop. For model planes, cars and boats this is never a big problem: They have no payload. So the acceleration to the maximum velocity is only lasting a second or less, and afterwards the ESC and motor are overdimensioned. By adding humans as payload we multiply the weight of our drives, and while going uphill with a RC car, you can always speculate that the model will get out of sight and the car has to go down again, so the powerlosses are moderate over time. Same is true for planes: Either your model climbs so high you cannot see it anymore, or your battery is empty. If you are sitting in this electric car going up 500 meters in height within 10 minutes, everything will get overloaded if you do not limit the phase current. So all electric vehicle controllers as a minimum protection will feature phase current limit, thermal shut down with a sensor near to the FETs and so on. If such a EV controller is rated for lets say 6kW, it really means it can take it for long period, and if it is overloaded, it will cut back without getting instable. If a Seaking 130A is rated for something it does not mean anything. It cannot control the changing situation by any means, it will just put out the dutycycle you provide by your remote, aka the voltage.
This is why i use the VESC, but i must admit, it is not powerful enough and will reduce the power too early for my needs. Also here, it is a matter of cooling, at least the power reduction based on the temperature sensor somehow works without destroying anything.
Also other EV controllers could work for our needs very well, but they need the same cooling effort.
Thanks for your opinion!
Like you wrote I will oversize the equipment, buy a SUP foil for less speed and add temperatures alarm for the ESC and an hall sensor to read the current.
Hello
I’m not an electrician, but what I’ve guessed everyone is that the engine under 130 amps must pull because the esc is designed only for it. The SSS 700 pulls but max. 197 amps and will destroy your esc. Correct me if I’m wrong.
Generally devices can overamp for short amounts of time. The ESC says it’s rated to 600 or 700 peak current I believe. 130A is the continuous amperage.
You might have an counterfeit seaking? Read somewhere that it’s many of them out there. They probably have less protection circuitry.
We burnt one(reverse polarity, stupid mistake) , but now we have two that have worked perfectly for a long time with different foil setups. 500kvss 142mm prop.
The heat and low volt cutoffs also seems to work well on these.