brushless motor stops when above 45% throttle

[ChewieTheWookie]

A friend and I want to make a plane but first we were testing the electronics. The servos all work great but we are having some issues with the brushless motor and/or ESC

The motor starts and spins up when you increase the throttle. However when the throttle is over ~45% then the engine runs for a 2 or 3 seconds before it dies. Then it beeps a couple times and then you can get it to spin again at low throttle.

We use the following parts:
- Racerstar BR2208 2600KV 2-3S brushless motor: https://banggood.onelink.me/zMT7/itcocv6c
- XXD HW30A 30A brushless ESC: https://banggood.onelink.me/zMT7/ctapy8mk
- Turnigy nano-tech 6000mah 2S 25~50C Lipo Pack: https://hobbyking.com/en_us/turnigy-battery-nano-tech-6000mah-2s-25-50c-lipo-pack-xt-90.html
- Gemfan 6x4 6040 propellor: https://banggood.onelink.me/zMT7/5pdl7l24

We also used a volt meter to measure the voltage which was about 8 at the battery and about 3.5 near the motor. We noticed the voltage dropped to 0 when above 45% throttle. This makes us think that the ESC cuts off the power? We did try to set the cutoff to the lowest level (3V) but that didnt change anything noticable compared to the high cutoff (3.5V)

Does anyone know how we can fix this problem?

 

[tamuct01]

It's likely a bad ESC. I don't have the exact specs of that motor, but a similar 2208 2600kV motor should top out at 16A at full throttle with that size of prop.
You may also check that the ESC is calibrated to your radio. This is usually done by setting your throttle to full when connecting the battery (take your props off!), waiting for the start beeps and then a secondary beep sequence, then setting the throttle to idle. The ESC will usually beep again and then be ready to go. You usually only need to do this once when setting up the power system.

 

[quorneng]

ChewieTheWookie
A 6000mAh 2s battery is pretty huge (heavy) for plane with a 6" prop but it certainly should'nt make any difference to the motor
I note the Banggood site gives a load of 15.2 A with a 6x4 on a 2s so should be well within the ESC's capabilities.
Does the motor still cut out at 45% throttle with the pro off?
If it does then it does its points to a problem with the ESC being unable to provide the appropate pulse timing. If it runs up to full speed then it suggest the amps being used is significant which could be either the motor or the ESC.
By far the best way is by sbstitution.
Does the ESC work properly with another motor. Does the original motor work properly with another ESC.
I keep a motor and ESC as a spare on my bench for exactly this purpose.
Another trick is to use a servo tester like this to control the ESC.

Plug the ESC to the tester output pins. The ESC BEC powers the tester and the tester provides the required signal to the ESC via the knob. from 0 to 100%. Doing it like this takes the radio out of the system so its one less possible problem area.
For safety always start any test with the prop off. You don't want an accidental burst of full power!

A new ESC may be a good starting point. If it solves the problem great! If it doesn't you will then have spare for future testing.

 

[ChewieTheWookie]

ChewieTheWookie
A 6000mAh 2s battery is pretty huge (heavy) for plane with a 6" prop but it certainly should'nt make any difference to the motor
I note the Banggood site gives a load of 15.2 A with a 6x4 on a 2s so should be well within the ESC's capabilities.
Does the motor still cut out at 45% throttle with the pro off?
If it does then it does its points to a problem with the ESC being unable to provide the appropate pulse timing. If it runs up to full speed then it suggest the amps being used is significant which could be either the motor or the ESC.
By far the best way is by sbstitution.
Does the ESC work properly with another motor. Does the original motor work properly with another ESC.
I keep a motor and ESC as a spare on my bench for exactly this purpose.
Another trick is to use a servo tester like this to control the ESC.
View attachment 225411
Plug the ESC to the tester output pins. The ESC BEC powers the tester and the tester provides the required signal to the ESC via the knob. from 0 to 100%. Doing it like this takes the radio out of the system so its one less possible problem area.
For safety always start any test with the prop off. You don't want an accidental burst of full power!

A new ESC may be a good starting point. If it solves the problem great! If it doesn't you will then have spare for future testing.

Yeah I have two engines (and two esc's) and no combination seems to work. It also stops without the prop. Maybe we'll try buying a servo tester and see if that works.

 

[skymaster]

Did you calibrate your Throttle stick?

 

[quorneng]

ChewieThe Wookie
With two motors and two ESCs it is perfectly possible with a bit of logical testing to determine which item is not performing correctly.
Then you simply just replace it.
If the testing has the same effect on any combination of motor and ESC than you have two or more failed items and you may have to replace the lot. This situation would then raise the question that you might have done something that caused such a number of failures.

 

[Bricks]

Which transmitter and receiver are you using it could be some programing in the radio that is causing the issue. DID YOU CALIBRATE THE ESC?