Author Topic: jeti spin 99 overheating??  (Read 333 times)

Offline Alan Williams

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jeti spin 99 overheating??
« on: 18, June 2017, 01:57:38 PM »
Flying this morning in the current hot weather and I had an issue, starting on the third flight of the day. After 4 minutes I suddenly had no response to the throttle. I landed but by the time I was down normal response had been restored. I checked the temp of the esc which was at 67 degrees with a recorded max of 85 degrees. On the next flight, similar symptoms but measured max temp on that flight was 78 degrees. Again after landing, static tests proved full power was again available. The max temp is set at 100 degrees on the jetibox.
So is this an overheating issue, which seems unlikely given the recorded temperatures, or is there some other issue that anyone has come across which could cause this??
any help appreciated.


Al. Williams

Offline Ashley Hoyland

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Re: jeti spin 99 overheating??
« Reply #1 on: 18, June 2017, 06:01:05 PM »

Hi Alan


I would start by deciding if there is a better place to mount your speed controller with good airflow. 


It has been known in some airframes to mount a fan on the speed controller.


Ashley




Offline Alan Williams

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Re: jeti spin 99 overheating??
« Reply #2 on: 18, June 2017, 06:15:32 PM »
The thing is that the esc has been mounted in the same place since i have owned it and before that by Gerhard who used it extensively with no issues,as far as i am aware. Clearly something has changed, maybe outside air temp, or possibly the prop.
As you say Ashley, time to experiment a bit. I just wonder why the protection is set at 100 degtees and i never exceeded 85 and yet someting cut off
All too mysterious


Offline Alan Williams

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Re: jeti spin 99 overheating??
« Reply #3 on: 19, June 2017, 03:18:24 PM »
Well, here is a conundrum. Flew again today, same symptoms. that is 3 flights all OK 4th fligt no throttle response after about 4 mins flying, power restored after a few moments. All temps etc. within range. So, I swapped the esc for another, that exhibited the same problems on the very next flight. Could it be the motor? But why would it fail to respond then be ok again, battery voltage was over 37.5 volts at the time of failure. So could be motor, or transmitter or receiver I guess. How bloody irritating!!


Offline Nigel Armstrong

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Re: jeti spin 99 overheating??
« Reply #4 on: 19, June 2017, 08:33:57 PM »

Hello Alan.


Give the connections between the motor and ESC a good check. Are they a good tight fit? If there all OK I would try changing the motor, if you have a spare available. Do you have another model with a similar motor in it that you could fit the first ESC into to try and check that out.


Good luck with your investigation.

Offline Alan Williams

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Re: jeti spin 99 overheating??
« Reply #5 on: 20, June 2017, 09:32:23 AM »
Thanks Nigel,
The only thing i don' t have spare is a motor so i will be able to test everything else and then if that all works assume it is a motor issue. At which point i think i will send it off to be looked at. I have to confess that i bought it second hand and have flown it a lot. So maybe its a bit old and tired like me!

Offline Alan Williams

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Re: jeti spin 99 overheating??
« Reply #6 on: 20, June 2017, 06:39:47 PM »
Well here is the interesting thing. I used a different plane today and experienced the same issues BUT, the esc showed the error when the problem occurred. Note I was deliberately forcing lots of power through the system and blanking the airflow over the esc.. The ESC cut off at 100 degrees C, as it should. I could replicate this very easily on the ground and by connecting the Jeti box, watch the temperature rise as I increased the throttle. At 100 degrees Bingo the motor cut and as the temp of the esc dropped below 100 it became active again. The jeti box also logged the error as T = Y So far so good, it was just as we expect. ON the other model, exactly the same symptoms BUT the esc never went above 85 degrees and no errors were logged. I think it is clearly a temperature issue as it has never happened before and 32 degrees C in the UK is most unusual. I have checked all connectors and it happens with both new and well used batteries, as the Hacker is very old and very well used,  to be safe the motor is out and off to Hacker to be overhauled.