cartec01

I'm hoping somebidy can help me. I have a park 370 brushless motor, Pheonix 25 amp speed control, futabu radio, a 6.6-1 gear box with a 12x6 prop. I am running a 3 cell Lipo. I am having a problem with the motor that I can not figure out. At low...(pretty low) rpm it runs smooth, but when I up the juice it starts cutting out, kind of like backfiring. I have adjusted the speed control for lipo batteries, and tried the cut out hard at 9v. I have also tried different over-current settings, and finally turned over-current protection off to see if that would help. Still doing the same thing, the motor with cut-out for about 1/2 second or less (kind of like a hickup) then run smooth for a second or two then the same thing. sometimes it will go multiple seconds before cut-out. when I give it even more juice it does not get worse. The plane is an e-flight ultimate, so it is extremely light, and it does this in flight. It is only a little worse in my hobby room when I hold the plane still. I don't know how to check the amps, but according to motocalc it is around 14 amps or so.
Can somebody help, I don't know enough about electric to fix the problem any further.

cartec01

Sorry about the spelling mistakes, I am typing fast.... Also I have tried different advances on the timing. I have the wires hooked up black to black, red to white, and white to red. The manual said to reverse any two wires to reverse the engine...

exeter_acres

My Feedback: (2)

What is the battery capacity and C rating??

sounds like the battery can't provide the juice needed

cartec01

The battery I am using is an E-Flight Thunder Power 11.1v 2100mah.
Maximum Continuous Discharge : 8.5C


Maximum Burst Discharge : 12C


Maximum Continuous Current : 18A

exeter_acres

My Feedback: (2)

Hmmm...battery should do.... try cutoff at 7.2 and set the cutoff to soft

Now... DO NOT fly until the battery is dead......

fly it and see if that does it... but your battery should be OK....

is it taking a full charge??

rcfury

My Feedback: (5)

How much current are you pulling. With the 12in prop you gotta be pushing some amps.

cartec01

I have several different lipo batteries. I have tried 4 different kinds, then I decided to try the one from my Edge 540T, and it seems to work. I don't understand it as it has about the same specs as the others. I use the same charger for each battery. I don't know how to measure the amps, but I can put a volt meter on it to see where the volts are falling for each battery. I'll try lower the voltage cut-off and see if that makes a difference with the other batteries. My only concern is that maybe the Thunder Power batteries have some protection built in to them, and the Edge battery does not, and it might balloon on me in flight and possible start fire if I am working it to hard. Does it sound like my setup is pulling a lot of amps?
Thanks for all your help....

rcfury

My Feedback: (5)

Well usually if your batteries are really hot you are pushing your batteries really hard. What speed control are you using with the other plane? Same settings?

cartec01

The other plane is a Parkflyers Edge 540t, it has some kind of an outrunner motor....and I don't know about the speed controller.
When I went out to fly with the different battery, it started cutting out like the rest. The batteries are getting warm at best at the end of a 5-10min. flight. I thought what I had seemed like a pretty common setup, and it is everything the Horizon Hobby recommends on the box for this Ultimate, but I know it shouldn't cut out like this.......

redfox435cat

my first thought is the speed controler is too small. try either a 35 amp controler or go to a 2 cell lipo. I would sy the reciever is crapin out but you mentioned it works with other batterys

cartec01

Ok, I put a meter on the see what amps it is pulling. It is cutting out just short of 14 amps. I do have any safety feature on the speed controller turned off and it makes noe difference. I have not tried the reciever in another plane, only the batteries. I have a Hitec mini 55 reciever and I will try that out to see if it makes a difference. Also, I bought another brand new Park 370 motor and it does the same thing, so I believe it is somewhere in the speed controler or the reciever... Any other ideas?

Flypaper 2

You really need to buy a Wattmeter. When it's hooked up you can crank it up to full throttle and see the voltage drop and the amps being drawn. You'll probably see the volts drop till the ESC cuts it out. Maybe the batts are not getting a full charge. Maybe overheated to many times and won't hold a charge. How many amps is being put back into the batt. after a run? Wattmeter will tell you what you need to know. Try borrowing a known good batt. from a friend for testing. As long it's over 2000 ma it shouldn't cut out till it's pooped out.