[NSRCA-discussion] JR DSM glitch - trouble-shooting.

[James Oddino]

I don't believe a bad battery could cause the engine to rev up unless  
your battery failsafe isn't set properly.  Make sure it is.

The first thing I would look at is the possibility that the throttle  
servo is stalled at low speed.  That could be pulling the battery/ 
voltage regulator voltage down and it could recover after you started  
to throttle up and removed the heavy load.

Finally I would run a one amp discharge test on the battery after it  
is fully charged to see if the battery is near its original capacity.   
The best way to do this is to plot the voltage vs. time taking  
readings every 5 to 10 minutes.

Hope this helps.  Let us know what you find.

Jim


On Apr 25, 2009, at 4:30 PM, cchariandy at yahoo.ca wrote:

> I had a close call today with my R921 Rx in an Integral.
>
> I noticed on taxi out that the engine rev'd up and quickly back down  
> without any command. At first I thought I must have bumped the stick  
> by accident. Then just before take-off there was no responce from  
> the throttle for a second or two then it was back. I thought the 170  
> may have loaded up a little and didnt respond. It did that one more  
> time before I aborted the flight. However, I could'nt reproduce the  
> problem in the pits.
>
> Before powering down, I checked for holds or fades on the data  
> logger - nil.
>
> Battery voltage droped from 8.2V to 7.8V and 7.6 under 1A load. When  
> I re-charged it took 350mA and I was only on for 3-4 mins.
>
> Now...I did accidentally run the battery down to like 5V during  
> winter but it did eventually recharge.
>
> I'm using a Jaccio perfect switch/6V regulator, Jaccio 2000mAHr (1  
> season
>
>
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