Power Pack C problem

[mrwhiskers]

So i recently built an FT Bushwacker with stock Power Pack C, and after a few successful flights, Ive stated having problems with the motor. I'm running a APC 10X4.7 Slo Fly prop and after about 3 or 4 minutes it makes some kind of a digital beeping from the motor and loses power. This happens before the voltage alarm goes off, which is set to go off at 3.5 Volts per cell. I got a new ESC, and that didn't work, and a new motor, and that didn't help either. I don't think the prop is the problem, because my friend has a Guinea Pig with the same motors, escs and props. Perhaps the receiver? Im just not sure......

 

[kacknor]

The beeping is coming from the ESC not the motor, and usually indicates low voltage. As it does, it's cutting power to the motor to save the battery. On most ECSs there is a programming option to change the motor cutoff to only reduced power to allow for a safe landing. That is the main problem IMO. Don't know on yours if you can also change the voltage cutoff on the ESC, its likely set to bottom out at 3.60v and causing things to shut down before your warning.

JD

 

[William A]

The beeping is coming from the ESC not the motor

The beeping noise DOES come from the motors, via the ESC.

It's the ESC talking, but the motor makes the noise.

 

[dropitlow88]

What type and rating of batteries? May have voltage sag when it is nearing the end of its capacity.

 

[jamboree1]

Just wondering, is this all on the same battery? have you tried others?

 

[TexMechsRobot]

I'm having a similar issue I think. This was my maiden flight and it only lasted about 2 minutes.

mrwhiskers, does the noise at 1:45ish sound like what you experienced? I don't know how to fix this either...

 

[Mytmerc83]

Not sure what the power pack "c" comes with but there is lots of talk in this forum on it. I my experience with the emax motor a 30amp ESC is not enough and puts the ESC into auto shut down due to heat. I have built several bushwackers, ft 3ds and have moved them all up to 40amp ESC and problem is gone. Maybe this is your issue?? I tested with a watt meter and was still under the 30amps but very close and gets to hot.

 

[TexMechsRobot]

That might be worth a shot. Thanks for the input!

It just seems unlikely that FT would sell a power pack that isn't tuned correctly.

 

[TexMechsRobot]

Based on this site, the motor shouldn't pull more than 20 amps. The 30 amp ESC should be plenty. I guess I could hook up a watt meter to see what the actual draw is.

http://www.headsuphobby.com/Emax-GT2215-09-1180kv-Outrunner-Brushless-Motor-C-691.htm

 

[Mytmerc83]

Yup that's the motor I run 7 or 8 of them from my guinea pig to my bloody baron. In the bushwacker and ft 3d with a 10x4.7 sf prop the watt meter shows 27amps which to me is boarder line?? But it would heat up te ESC enough to go into auto shut down. I'll try to post my guinea pig video of my maiden when it actually cooked one ESC and death spiralled the plane into the ground. The guinea was making the same sound!

 

[Mytmerc83]

Hope that worked!! Not real good on these things.
About 2:25 in this video you can hear it. And then it locks up.

 

[TexMechsRobot]

Sounds like your experience is exactly like mine. I need to invest in a watt meter anyway and this would be a pretty good excuse to do that early in the hobby. I had avoided it so far thinking that the kits I was buying would already be tuned correctly. I plan to scratch build in the future and a watt meter will come in handy for sure.

If I'm anywhere close to 30A then it would seem likely that overdrawing would be the culprit. Unfortunately, I have no money in my RC budget at the moment lol. Might have to wait a while before I can take this step.

Thanks for the opinion. I'd love to see your video if you still have it.

 

[Mytmerc83]

It took some time and planes to figure it out but have not had an issue since. Good motors can take a crash and keep going. My son really like to put that to the test!!! ( I still meet the earth hard on occasion). Only had to replace the one from the guinea pig as it burnt up.

 

[Mytmerc83]

The other thing that had me Scratching my head was I build a buddy a bushwacker and he was running eflite 3s 2200mah 30c and had no issue, I ran 3s 2200mah 50c and would make me dead stick land all the time. I put one of my batteries in his and same thing would over heat. Then after 5 or so flights his would start to over heat on the eflite battery. I think it's cause he would run one constant throttle setting the whole flight. (He was just starting out).

 

[TexMechsRobot]

My current setup is shown below. The only difference is the battery mAh is not right. I'm beginning to think that the 4s battery is too much. I appear to have purchased the wrong battery from the start!! According to the other website I linked earlier, it should only have 2s or 3s on it. I'm new to this hobby and I'm not really sure how to calculate the correct electronics!

 

[Mytmerc83]

Yup that would do it alright!!! 4s is too much for that motor for sure. It's got to be very hot to the touch after a flight? Easy rule( I'm sure others will pipe up) is 5 seconds!! If you can't hold the motor/ESC for 5 seconds after a flight set up is wrong.

 

[TexMechsRobot]

Thanks for all of your help. The battery is definitely the problem. I made a mistake when I bought it from Flite Test. They recommend the 3s and I accidentally purchased the 4s.

I will wait until I have money and buy the correct battery. I bet that will fix all of my problems.

 

[Mytmerc83]

Still remember the ESC issue. As you get more 3d or harded flying it could still be an issue. I myself would still pick up a watt meter they are worth it. Good luck, happy flying.

 

[mrwhiskers]

I think I have solved the problem! I cut a triangular opening in front of the windshield that leads down to the Power Pod. (note: this is 3 layers of foam) If I run it at full for like 3 minutes it does start to do it, but for just short bursts of full power it does the trick.

 

[TexMechsRobot]

So overheating was a problem for you. Good to know that a simple nose vent can alleviate the heating problem!