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jutty
08-16-2005, 11:27 PM
Help! I am running a slow stick with an E-Flite 370 brushless, Great Planes 7.4 volt 1500Mah lipo, stock gear box, 12X6 prop, Phoenix 25 brushless speed controller.
Here is my problem: after take off the motor cuts in and out. I thrashed one motor because I kept flying it with it cutting in and out. So I am on my 2nd motor and don't want to thrash this one I have tried hooking two batteries in parallel on the old motor and it didn't help. Any advice would be helpful!!

Jutty

EpoweredRc
08-16-2005, 11:45 PM
Help! I am running a slow stick with an E-Flite 370 brushless, Great Planes 7.4 volt 1500Mah lipo, stock gear box, 12X6 prop, Phoenix 25 brushless speed controller.
Here is my problem: after take off the motor cuts in and out. I thrashed one motor because I kept flying it with it cutting in and out. So I am on my 2nd motor and don't want to thrash this one I have tried hooking two batteries in parallel on the old motor and it didn't help. Any advice would be helpful!!

Jutty

I am not 100% but sounds like you might be useing to big of batteries.The 370 is around the same as the Himax 2015 that I run I only use up to a Thunder Power 1320 Pro Lite 3 cell with it.Again Im not sure but this could be why.Does the motor and or esc get hot?

jutty
08-16-2005, 11:51 PM
The guys at E-Flite think I need more power (amps) and suggested wiring two of my batteries in parallel, but I already tried that. A Thunder power 1320 3 cell has one more cell than mine (7.4 vs 11.1 v). It has less Mil AMps but more volts. The ECS doen't get hot but the motor does. Is this any help?

EpoweredRc
08-16-2005, 11:53 PM
The guys at E-Flite think I need more power (amps) and suggested wiring two of my batteries in parallel, but I already tried that. A Thunder power 1320 3 cell has one more cell than mine (7.4 vs 11.1 v). It has less Mil AMps but more volts. The ECS doen't get hot but the motor does. Is this any help?

I would think that it should be flying really good.So is the 1500 pack a 4 cell?

The TP Pro lite 3 cell isalso 11.1 V same as your 1500 has 11.1V
your caplity is bigger being a 1500 and the 1320 but its not good if your not getting the full amount from the battery.

I would think 2 1500 in parallel would really be putting some power to it.

jutty
08-16-2005, 11:57 PM
Ea battery is a 2s2p(2 cells in parallel) when both are wired together it is a 2s4p (i think)with a total of 3000 mah. My guess is my prop is too big but that is just a guess.

EpoweredRc
08-17-2005, 12:01 AM
What kind of lipo are you useing?

EpoweredRc
08-17-2005, 12:02 AM
Ea battery is a 2s2p(2 cells in parallel) when both are wired together it is a 2s4p (i think)with a total of 3000 mah. My guess is my prop is too big but that is just a guess.

oh your useing a 2 cell. I think you need a 3 cell,your not giving it enough power for that motor set up what gear ratio are you useing?

EpoweredRc
08-17-2005, 12:11 AM
I would think that it should be flying really good.So is the 1500 pack a 4 cell?

The TP Pro lite 3 cell isalso 11.1 V same as your 1500 has 11.1V
your caplity is bigger being a 1500 and the 1320 but its not good if your not getting the full amount from the battery.

I would think 2 1500 in parallel would really be putting some power to it.

So the 2 cell your useing are 7.2 V,you need a 3 cell witch is rated 11.1V to get that thing flying or maybe you could try a smaller prop maybe a 11x4.7.

I am about to leave so I wont be able to reply back for a while,I hope someone else can help you.Sorry I didnt understand what you had at first.

trogdor
08-17-2005, 12:12 AM
What is the gearing on that? The GWS gearboxes have spur gears (the big one) with letters on the front. Probably a D gear and I assume the 10 tooth pinion gear came on the motor shaft.

Some people run 3s 11.1V lipo packs on D gears (6.6:1 ratio) with a 12x6 prop with that motor for 3D. hmm..

oh wait, is that the 5400kv motor or the 4100? If its the 5400, that could be the problem. The prop would be kinda big in that case possibly causing overheating. I'm surprised its the motor though and not those battery packs. The motor cutting in and out is usually the ESC detecting that the battery is sagging voltage-wise so much that it thinks its almost empty. That happens when you draw too much current by using too much prop and this usually heats the battery pack up.

In any case, jutty is right in that a smaller prop will put less of a load on the whole system. Try a 10x8 maybe.

jutty
08-17-2005, 12:12 AM
Great Planes batteries, I asked the guys at E-Flite if I should try wiring them in series (4s2p) and they said no is parallel. At this point I am abot willing to try antything.
I do not know waht gearing it it but it is the stock GWS gear box and gear.

jutty
08-17-2005, 12:15 AM
The motor is a 5400kv, the gear is a "D". Wouldn't wiring the batteries together to get 3000mah solve the "sagging" problem??

trogdor
08-17-2005, 12:28 AM
Yes, theoretically! That's assuming the battery was the problem, but you said the motor got hot... and I think its just because you have too much prop. That motor is made to spin relatively fast compared to others to spin smaller props for faster planes. So when you lug it down with a big prop, it still tries to spin fast but just ends up drawing a LOT of current that just heats it up.

Try a 10x8 or maybe 11x7HD GWS prop... and check motor and battery temps every couple mins while flying until you know its a safe combo... motor can be very warm.. very hot is probably bad.. lipos can be a little warm but any kind of hot is really bad and will shorten their useful life considerably. So are you sure the last motor is dead? Did the magnets shatter or something? I had that once where the motor wouldnt even turn anymore and if you forced it with pliers it was all crunchy! Let us know how it turns out.

EpoweredRc
08-17-2005, 04:02 AM
Great Planes batteries, I asked the guys at E-Flite if I should try wiring them in series (4s2p) and they said no is parallel. At this point I am abot willing to try antything.
I do not know waht gearing it it but it is the stock GWS gear box and gear.

I have no expreice with Great plane packs,but I think you need a 3 cell pack rather it be a Poly quest 830 or a TP pro lite 1320 anything around that that is 3 cell,2 cell will fly planes but not with much power.you want enough power that the plane doesnt stall on you and crash.

trogdor
08-17-2005, 04:39 AM
Well, I'd agree on some planes, but this is a slow stick! It'll fly at 2 mph!Another way to look at it is the stock 350 motor it came with had a kv of about 4500ish?? I can't remember exactly but its pretty high. Anyway, the new motor has a kv of 5400 so on the same 2 cell pack used with the old setup you'd get more rpm out of the prop and more efficiency so it has to be at least a little better. 3 cells would be better but you'd have to drop the prop to 8 inches to keep it in the limits.The Great Planes packs are just Kokam cells. teh 1500 is really like a 6C pack putting out around 9-10 amps max before it sags bad and slowly gets weaker over time like all mine did! However, they should be fine for a slow stick and this motor with a prop that doesn't overload any of the components.

EpoweredRc
08-17-2005, 04:44 AM
Well, I'd agree on some planes, but this is a slow stick! It'll fly at 2 mph!Another way to look at it is the stock 350 motor it came with had a kv of about 4500ish?? I can't remember exactly but its pretty high. Anyway, the new motor has a kv of 5400 so on the same 2 cell pack used with the old setup you'd get more rpm out of the prop and more efficiency so it has to be at least a little better. 3 cells would be better but you'd have to drop the prop to 8 inches to keep it in the limits.The Great Planes packs are just Kokam cells. teh 1500 is really like a 6C pack putting out around 9-10 amps max before it sags bad and slowly gets weaker over time like all mine did! However, they should be fine for a slow stick and this motor with a prop that doesn't overload any of the components.

Oh okay,well first of all get rid of the Cheap packs and get some good ones either Poly quests,I rates or Thunder Power Pro lites

Sorry.I dont like kokam,anyways Okay so it will fly very slow, just change to a smaller prop and try it.

trogdor
08-17-2005, 04:47 AM
I do agree on the pack choices. Put this motor in a GWS Zero or Formosa when you're ready and a good 3 cell lipo and watch out!

jutty
08-17-2005, 03:44 PM
I got some smaller props to try today (if it is not to windy) also I grabed my 11.4 3s2p 3000 maH pack out of another palne to try. I'll keep you updated. By th eway the batteries are not great planes they r Electrifly.

EpoweredRc
08-17-2005, 04:06 PM
I got some smaller props to try today (if it is not to windy) also I grabed my 11.4 3s2p 3000 maH pack out of another palne to try. I'll keep you updated. By th eway the batteries are not great planes they r Electrifly.

Oh allright,good luck with it.so them are 3 cell that should fly the plane good,just with one of them. but strap both and see what you got.

t. edwards
08-17-2005, 07:52 PM
E-Flite 370 inrunner 3600kv with 12x6 prop 2s lipo needs 6.6:1 gearbox. Higher kv motor or 3s or less gear reduction will need smaller prop. Have run the 370 3600kv, 12x6, 6.6:1, 2s, Phx 10 amp esc, and it works very well.

Turbojoe
08-18-2005, 12:56 AM
What's your LVC set at? If it's too high it'll cut out just like you're experiencing. For 2S packs make sure it's set at 6.0 volts (3 volts per cell).


Joe

trogdor
08-18-2005, 02:15 AM
You should be able to fly a year with that huge pack although remember to prop WAY down.. 8 inch prop range on that higher voltage.

EpoweredRc
08-18-2005, 02:22 AM
What's your LVC set at? If it's too high it'll cut out just like you're experiencing. For 2S packs make sure it's set at 6.0 volts (3 volts per cell).


Joe

Good point I didnt even think about that,you need to check your low voltage cutoff and make sure its not set to high,but dont set it to low or you will kill the battery.

jutty
08-18-2005, 03:43 PM
I am not sure what the LVC is set at, the guy @ Hobby Town set it up 4 me.
So last night I installed a 1147 prop and it only cut out a few times under full throttle. It was super windy so I just did the check and landed. I now have a 1060 prop on it and I am waiting for the wind to calm down. I most likely won't be able to fly it today due to wind. I did not try my 3s2p since it was so windy yesterday, and I really don't want to run that battery when I already have 2 of the smaller batteries.

Turbojoe
08-18-2005, 10:32 PM
I am not sure what the LVC is set at, the guy @ Hobby Town set it up 4 me.


You need to make sure the LVC is set corretly mainly for the sake of your batteries. If you pull them down below 3 volts per cell you can permanently damage them. I have a pack that was destroyed this way.
The Castle Creations ESC's are very easy to program. If you don't have the instruction sheet it's available on the Castle Creations (http://www.castlerc.com/)website under "documents". If you want to make it fully upgradable then get the Phoenix Link programmer and do everything from your computer.


Joe

EpoweredRc
08-18-2005, 11:08 PM
You need to make sure the LVC is set corretly mainly for the sake of your batteries. If you pull them down below 3 volts per cell you can permanently damage them. I have a pack that was destroyed this way.
The Castle Creations ESC's are very easy to program. If you don't have the instruction sheet it's available on the Castle Creations (http://www.castlerc.com/)website under "documents". If you want to make it fully upgradable then get the Phoenix Link programmer and do everything from your computer.


Joe

Yes,what he said :D

EpoweredRc
08-23-2005, 04:16 PM
So did you fly it,how did it do?

jutty
08-23-2005, 05:51 PM
I went to a 1047 prop and wired the batteries in Parallel and it seemed to help it cut out a few times but not bad. The motor did get really warm. I did not get a chance to try the 3s2p in it yet. It has been pretty windy here for the past few days.

jutty
08-25-2005, 04:31 AM
I put the 3s2p in and it still did it!!! What a bummer my next step which I have already set up is a Phen. 35. I borrowed it from one of my other planes. We will see how it goes. If this fixes the problem then I will send the Phen. 25 back to Castle. I have a funny feeling it is the motor seeing how others have had problems. Talking the the guy at RC Country in Sacramento, he siad he had alomost the same setup with 3s2p and he had no issues (same motor).

Turbojoe
08-25-2005, 04:56 AM
Have you programmed the proper Low Voltage Cutoff yet?



Joe

jutty
08-25-2005, 03:23 PM
The 25 Amp has auto Lipo detect and it seemed to detect the right # of cells. After I put the 35 amp on I read the directions and it does not have an auto detect. I set it up but haven't tried it yet. To windy. I then manualy set up the 25 amp just in case the auto feature wasn't working correctly. I will reinstall it if the 35 doesn't work right. Which means that the motor is crap.

rc crashburn
08-25-2005, 11:18 PM
What receiver are you using? Maybe the receiver is glitching thereby causing the motor to cut in and out.