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| ShellDude | Elite Veteran - Location: East Coventry, PA - My Posts This: Topic Forum |
Ok, here it is.
Lets just say I didn't go easy. I whipped her around quite a bit and didn't hold back until the end. I've been warned that the voltage drop-off at the end is quite abrupt... and well, you'll see that soon enough 
Will start with just the basic numbers and provide some observations/conjecture for each:
Amps vs Volts
Do you see the abrupt voltage drop at the end? That wasn't anything frying. It was simply the pack/turbo module saying "times up". The end of discharge signs were very subtle, as you can see by the downward slope that started at about 310 seconds. I felt it and got her to about 10' off the ground. I was expecting the Jazz to do its normal power down but it fell off RATHER QUICKLY. I just barely had enough time to hit Throttle hold and pump the collective to get her on the ground without damage.
If I wasn't a grown man, I would've cried when first looking at this chart. The voltage sag is very evident at the 12V setting during high amp maneuvers.
The flipside is that I have a completely variable voltage setup. I can dial in my desired headspeed by selecting the voltage on the turbo module. I forgot to bring my tach out with me but my best guess is that my HS was at approximately 2,800 RPM at this setting.
Unfortunately, you pay a price for stepping up voltage, and it's in cummulative mAH, as illustrated below:
Cummulative mAH vs Watts
I got a bit over 1,260 mA out of the pack before shutdown.
I decided to include WATTS on this chart simply because I was so impressed with how much power I was able to pull. One of my peaks were at 373 watts!
The scary side of this is what the numbers would've looked like between the Turbo module and the battery pack. If you recall in my last test, I put my Eagletree between the pack and Turbo module with it dialed in at 10.8V. I really don't want to know what the numbers look like at the 12V setting. I bet they're through the roof!
Amps/Volts vs Turbo Module Temperature
I included this chart because I want folks to see how close to the limit I'm at with the current Turbo module. The core temperature of the module is a bit more than what my probe was able to capture. Post flight, I held it firmly in my hand I'm going to wager that the module was at about 130F.
It has been rumored (and I'm currently unable to either confirm or deny this) that a more robust module is in the works. When / if I learn more about this development, I promise to pass the info along.
In the meantime, this'll probably be my last published test with this setup for a while. It's been fun but I've got a couple other projects I want to focus on.
If you decide to go this route, bear in mind that A123 considers using their Turbo Module in an RC Helicopter an unsupported platform. If asked about it, they'll probably tell you flat-out to not try it, and I understand why given the nature of the end of discharge cutout... man it came quick!
Happy Flying!
Shell
~~OCHC~~
http://www.glumbert.com/media/spiders |
| 09-30-2006 Over year old. | | | |
