a123 on the protos

[kgfly]

The solution may be to run Hyperion G3 5S lipo (which hold very high voltage under load) but I guess you want to use a pair of existing 3S lipos in series. Finding a setup that works well for both 7S A123 and 6S lipo could be tricky, but it should be fun trying

[synergy41]

hi
someone try 8s
best regards
pascal

[JustPlaneChris]

8S A123 would neither fit under the stock canopy, nor balance properly. 7S is perfect, if you want to run A123.

[synergy41]

thank you very much

[rcboosted]

I have limited success with Scropion 880kv on 15T and 100% throttle curve using a 7S A123 on my Protos. It has ok power when the pack have been warmed up, but due to the extra weight, it's a little dampened, and I only get 3:30 out of a pack! I do love the fact that I don't have to time the flight, charges quickly, and not having to worry about having to discharg the pack by the end of day Sunday. And I agree that it's a little tough to switch between lipo and A123. My lipo is running a 85% throttle which is still a little high, while the A123 is running 100%, which is still a little low. Going to 16T would probably be too high for my lipo. I might try it.

[ayash]

Originally Posted by JustPlaneChris

8S A123 would neither fit under the stock canopy, nor balance properly. 7S is perfect, if you want to run A123.

7S A123 - Good yes, perfect no. Doesn't balance perfectly.

[JustPlaneChris]

Originally Posted by rcboosted

I have limited success with Scropion 880kv on 15T and 100% throttle curve using a 7S A123 on my Protos. It has ok power when the pack have been warmed up, but due to the extra weight, it's a little dampened, and I only get 3:30 out of a pack!

Something isn't right then.... I'm running that same setup, and it's way better than "ok power" even on cold packs. It's enough power to win the drag race contest at our local fun fly, in fact. I also get over 5 minutes of flight time. What ESC are you using, and with what settings for timing?

7S A123 - Good yes, perfect no. Doesn't balance perfectly.

True, it is slightly nose heavy. However, it has no detrimental effects on the flight performance so I consider it a non-issue.

[OnTheSnap]

Chris,
Maybe it's a gearing and motor kv thing? You use a scorpion 880kv and I assume a 15t pinion. With the stock 800kv motor I don't think you can hit 2800 rpm with a 15T pinion. With a 16T you can.

[rcboosted]

Originally Posted by JustPlaneChris

Something isn't right then.... I'm running that same setup, and it's way better than "ok power" even on cold packs. It's enough power to win the drag race contest at our local fun fly, in fact. I also get over 5 minutes of flight time. What ESC are you using, and with what settings for timing?

It's a CC 85HV on mid timing. I tend to like my heli on the snappy side, my other helis are 450s on 4S spinning to 3200rpm. So maybe I'm used to lots of HS. I got 5min when I had stock motor and 100% throttle. Scorpion brought it down to 3:30. Seems a bit extreme, but maybe I'm just flying more aggressive with more HS now.

[JustPlaneChris]

Wow, you must really be cranking and banging on it. Even turning 2800 I can get 5 minutes out of mine.

[kgfly]

Seems we need FDR logs at 10 paces

[OnTheSnap]

I threw in the 15T today and ran the A123 7s at 90% flat governed. It was much better. I also saw the average current drop from 23A to 20A. No RPM gauge yet, but here's the plot. I ran for 5 minutes, and it looks like I can do at least 6! I plan on running 6s LiPos at 80%. We'll see how that goes.

[ronnieb]

Strange things going on in electro land................

My setup is 7SA123, 18T, 94 main, hyperion 80a esc at 88% flat
running 2700 rpm for 5 min. Good for sports flying and modest 3D
after second charge!

This setup also is perfect for changing to lipo 25C.
Than running on 80% flat at 2600 rpm which seems enough
to hold a stable rpm.


Maybe it's because of the 93T maingear but this setup
really works well!

[JustPlaneChris]

Whoah... you are running an 18T on 7S A123 and 6S lipo??? That should be giving you totally INSANE headspeed, unless you've got a lower KV motor than stock...?

[ronnieb]

Like I stated, Chris, strange things!

Gov Rpm between 2600 en 2700 at arround 85% flat.

Maybe it's because of the 94T maingear I'm using.........
Standard MSH motor!

[JustPlaneChris]

Oh, I didn't catch that... where did you get a 94T main?? That would drop it down some, but it would still calculate out nearer to 3000. As you say, very strange.

[rcboosted]

Thought I post some updates. After warming up my packs and moving up to 16T on my Scorpion, the A123 pack is livable now. I'm pulling up to 70A sometimes. But weight is still the biggest issue, I can feel a huge difference between my 2200mah pack and the A123. But for fast field charging, these A123s can't be beat. With 4 lipos and 2 A123s and I can fly all afternoon. The 4 lipos get depleted quickly, then it's just charging 1 A123 while flying the other. The break between flights to cool the motor allows the 12min charge on the A123 to finish.

The biggest problem I have now is the governor on the new CC firmware. I'm hitting 150F motor temp all the time, and even hit 200F once.