TRex 450SE on 3S A123

[Mac_Heli]

Found some great technical info comparing lipos and A123 as far as power output. (last 2 posts)

http://www.archeli.com.au/cobra/showthread.php?t=112204

[Bill Sanford]

This place has the Scorpion motors in stock:

http://www.neoplanes.com/radio-contr...outrunner.html

Free shipping as well...

I should have a chance to get out flying Tuesday after work and should have some graphs for you Wednesday.

Bill

[JustPlaneChris]

Hey guys, we finally got a break in schedules and weather and I got to put a flight on rvsixer's CopterX 450 outfitted with 3S A123. Last time I flew it, it had 335 blades, a smaller pinion, and was much less lively. This time? It was great! I'll let the video speak:

rvsixer's CopterX 450 (5 min 22 sec)

[Bill Sanford]

Originally Posted by Mac_Heli

Found some great technical info comparing lipos and A123 as far as power output. (last 2 posts)

http://www.archeli.com.au/cobra/showthread.php?t=112204

The cells are rated at 30C continuous and 60C burst. I have ran them with peak currents at 100 amps (1p) with no ill effects on the cells.

I know I'm going to be nervous when I look at my Eagle Tree graphs because I'm likely drawing WAY more current than my Phoenix 35 is rated at... As long as the Phoenix 35 keeps working, I'll keep flying it! It actually comes down cool.

The lower pack voltage doesn't work the internal BEC circuitry in the ESC as hard as a 3S lipoly. In my experience in 450 sized helis, the BECs generate the majority of the heat in the ESCs (CC or Align).

Bill

[Bill Sanford]

The video looks good Chris. You just need to work it a bit harder!

Bill

[Mac_Heli]

I tested the 15T/430xl combination, and the first flight was weak, but the second and mostly the 3rd produced the same power as a 430L on 13T with 18C lipos. I charged the batt on my car's battery in 16min with the align charger at 5A. But after the 3rd flight the batt was so hot I couldn't hold them for more than 5secs, not to mention the motor, couldn't touch it for 2secs.
Today I ordered the scorpion motor (thanks Bill), material and cells for a 2nd batt (cheapbatterypacks) so I don't overheat the only one I have. My LHS has the 45A CC ESC and by the way Bill, if you check the link to the graphs I've posted earlier, you could peak at 63A!!!
I'll post the 15T/430xl graphs tomorrow (i forgot the laptop at work).

[JustPlaneChris]

Originally Posted by Bill Sanford

The video looks good Chris. You just need to work it a bit harder!

Bill

So true, Bill. But I'm rather timid when flying someone else's toy. It felt good though. Not crazy powerful, but certainly enough for some fun sporting around.

[uneverno]

Wow,
this is indeed intriguing. Forgive that I missed it - these are the same voltage as Li-Ion, so a charger with that capability could be used correct?

I'm also assuming they don't have to be charged that hard, it's just that they can be, so resultant shorter charge times, correct?

Thanks,

[wlfk]

You're right in that A123 cells don't have to be charged that hard. But you should only charge them to 3.6 volts (3.7 max).

Just bought a Scorpion -6 motor, and it does work far better on 14t than the 430x with 15t.

K

[Mac_Heli]

Scorpion is on Backorder, A123 stuff I ordered on Monday didn't ship yet, and the 45A CC ESC I got yesterday from my LHS is defective...(smoked my 430L at the LHS) LHS won't swap it, so 2 weeks waiting on warranty replacement from CC... I'm afraid to fly now, with my luck I'll crash it for sure!!
Bill, I got the Dan's voltage cut off project ready to be tested. Is that what you're using to charge the A123s?

[Bill Sanford]

I use a Mastech HY5020 to charge my A123 packs.

I also made up a zip cord for charging my 3S packs from a car battery. I'm using it with an Astro Flight watt meter in line (to measure capacity put back) and a cutoff device that I bought from Dan Baldwin on RC Groups. It works great!

Sorry that I haven't posted any graphs yet. I have a MacPro and run Parallels to run Windows and Windows died on me, so I can't download my data from my EagleTree recorder. (Did I mention I hate windows!!!!!!! If not, I HATE WINDOWS!!)

I'll see if I can get it to work this weekend, but the "honey do" list is long. I'm ripping up vinyl flooring in our entryway & kitchen and will be installing ceramic tile. My knees hurt already just thinking about it!! It will be nice when I'm done though... Sorry, off topic...

Anyway, hang in there with the A123 project. You'll get it to work and I think you'll be very pleased when you're done.

Bill

[Mac_Heli]

After the Castle Creations ESC soap opera resolved, I finally had a chance to run a couple of tests today. The 2221-6/13T combo kept an impressive 3100-3200 rpm for 5:30 min.(100-85-100). The motor and batt reached 125F and the ESC 120F. Battery charged in less than 10 min and reached 130F. My zip cord also reached 130F which scared me a bit, while charging at 14A. I only had time for a couple of hovering flights in front of the house, but so far I'm really impressed.
Bill, any idea how hot does your setup get?

[Bill Sanford]

Originally Posted by Mac_Heli

After the Castle Creations ESC soap opera resolved, I finally had a chance to run a couple of tests today. The 2221-6/13T combo kept an impressive 3100-3200 rpm for 5:30 min.(100-85-100). The motor and batt reached 125F and the ESC 120F. Battery charged in less than 10 min and reached 130F. My zip cord also reached 130F which scared me a bit, while charging at 14A. I only had time for a couple of hovering flights in front of the house, but so far I'm really impressed.
Bill, any idea how hot does your setup get?

Wow! 3100... That's great!

I set my timer for 5 minutes and flew so hard a few times yesterday that I had to land early because I was out of juice. Lot's of collective, lots of speed, big loops, hard full collective turns, etc., and making the power system work very hard!!

Concerning temps, I'm not sure what mine is running, but everything is just warm to the touch, so nowhere near 130F. All of my flights are moving VERY quickly, so that may help keep things cool. Also, temps up north here have been very cool this spring. I don't think we've been above 70 degrees yet. My zip cord is also just warm to the touch. Charging starts at about 19 amps.

What gauge and how long is your zip cord? If you're worried about the temp of your zip cord you could run a longer piece of lower gauge (thicker) zip cord to get the same resistance. The longer length of cord would help dissipate the heat better. I think my piece is about 6-8 feet long and I think it's 16 gauge (although I'm not absolutely sure). I just took a long piece of some heavier speaker wire I had lying around and tried it. Then I just cut it down until I had an acceptable starting current and called it good...

Still haven't taken the time to get Parallels working on my MacPro (did I tell you I hate Windows!!), so I can't get you any graphs yet. Sorry. Actually Parallels seems to be working fine, it's just a Windows issue... I guess I could take the Eagle Tree into work and download there...

I was out flying yesterday with a friend and we flew non-stop for three hours. I had an absolute blast. He flew, I flew, he flew, I flew... I must have got 20-30 flights in. I flew both my 3S A123 TRex 450 and my 12s A123 TRex 600. I had the zip charger charging my 3s A123 packs and the Honda EU1000i and the Mastech HY5020 charging my 12S packs. With 3 packs for my 600 and 2 packs for my 450, I never ran out of charged batteries!! Got to love A123s....

I'm great at all orientations, slow pirouetting, FFF, flips, rolls, etc. & fast tearing around. I started working more on inverted hovering yesterday. That will get your heart pumping. It was a blast. It's really fun when you get to the point where you can try just about anything and have the skills to recover when things go bad!

All in all, a great day. The helis flew awesome!

I also got my additional Scorpion HK2221-6 in my other TRex 450 and will check that out this week. This one has a 6 volt BEC so it should be snappier on cyclic and tail authority. It'll be great to be done with lipolys all together!!!

Our club has a fun fly this weekend and I'll be camping at the field, so I hope to get a bunch more flying in then!!

Life is good!!!!

Bill

[Mac_Heli]

Yep, I love this hobby too.... loads of fun, and when you're ready for some stronger emotions just push the heli a little more...
I just finished setting up my contraption (charger). It is a computer powersupply with 2 separate 12v lines, with 10A and 15A so I can charge lipos and A123s at the same time. I added Dan's cutoff circuit (works great!) and the zip cord (it is a 16awg by 20 feet). South Florida's morning is reaching 90F at 7:45am so the temperature difference may be playing a big part on my setup.
Another thing I noticed is the eagletree brushless rpm sensor doesn't like this setup. My RPM readings are a little weird, lots of dead spots of the graph, I don't know if I can really trust it... I can tell you the HS sound matches the 430xl/lipo setup both on the 12/13T pinions.

I had discarded the idea of a Trex600 in the past because of the Nitro mess or the pricey batts... A123s are getting the itch back, and Uncle Sam's check was on the mailbox today....

[Mac_Heli]

Hey Bill,
So far I'm loving the A123 setup. 2 packs, 10 minutes of charging and all I need is 5 min between flights. (charger will charge 2 packs at the same time). Today I had to stop flying because the radio batt pack ran out...
I'm considering a 500 or 600 now, running only A123s. Any suggestions?
Thanks

[terrybeb]

what about this charger will it work like the Zip charger mentioned?
http://www.horizonhobby.com/Products...odID=AQR400088

[Bill Sanford]

Originally Posted by Mac_Heli

Hey Bill,
So far I'm loving the A123 setup. 2 packs, 10 minutes of charging and all I need is 5 min between flights. (charger will charge 2 packs at the same time). Today I had to stop flying because the radio batt pack ran out...
I'm considering a 500 or 600 now, running only A123s. Any suggestions?
Thanks

The 600 works very well with 12s A123. This requires a new motor and ESC, but you can buy a stripped kit from GrandRC with just the airframe, so you can add whatever power system you want.

I've heard that the 500 works very well with 7s A123.

Lots of options...

Bill

[Bill Sanford]

Finally got my Windows working running Parallels on my Mac and posted an Eagle Tree graph in the A123 thread.

Check it out!

Over 50 amp peaks and over 400 watts.

5 minutes of hammering on it and I almost had to auto it in!

Not bad in a 450 bird!



Bill

[rvsixer]

Originally Posted by terrybeb

what about this charger will it work like the Zip charger mentioned?
http://www.horizonhobby.com/Products...odID=AQR400088

No, this is a charger, the zip charging method does not use a charger .

[terrybeb]

Thanks for the reply....I have more reading to do for sure. Quick question how many cells can you charge using this zip charging meathod?