Motors not starting up all the time

[Giovanni59]

Setup:
3520 T-Motors
Maytech 65 A Simon Flashed Opto ESCs
15x5 Xoar props
Latest WKM firmware flashed
Idle Speed set to max

Here is what happens every 4-5 times I start up:

http://www.youtube.com/watch?v=UBE8Ytv6_K8

Fast forward to about 1:17 to see #1 motor not starting

Anyone having this issue?

 

[Lanzar]

First off all.

Are all esc calibrated.
DID you check iff you change the motor 1 to esc 2 and esc 2 to motor 1 what hapenes.

Let us know more.

 

[BorisS]

If you didn't calibrate them ESC and 5 of the 6 are working calibration should not be the issue ! Simonk ESCs are defaulted to 1060us to 1860us. Given that WKM outputs the same on all ports.
If you did calibrate them than that could also be the source that something went wrong ! I would also check your wiring maybe some bad soldering and a phase has contact and than again not and so on !

"Since the 2012-01-04 release, the input throttle range may be calibrated. This should be used whenever PWM input mode is used, including where external resonators are present, to set the usable throttle range.
The default range is set at the top of tgy.asm (stop at 1060us, full throttle at 1860us) and is not changed if no new value is saved to the EEPROM."

Boris

 

[Giovanni59]

I calibrated them with a snake I made so all the ESCs can be calibrated at the same time. However I am not sure what signals I am supposed to get if calibration is successful. I am using a Spektrum DX8.I am learning from others that on larger props this happens occasionally and does not effect actual operation, only start up. The ESC wires are soldered to a copper bus bar and I inspected them carefully before assembling everything. I did take a good photo and you can see the nice solder flow. View attachment 11975

 

[BorisS]

Hmm Giovanni I would`t go by the statement only occasionally and does not effect the actual operation ! You wouldn't drive you car if the one of the brakes don't work when you start it, but once you get the brake running which happens occasionally than its safe to drive off.

I would do the following steps.

1. Check the soldering not only the part were the ESC are connected to the distribution but the part were the three phases of the motors are connected.

2. Change components around like lanzar already suggested ! See if you can find the component that caused the late startup or the not starting at all problem.

3. Recalibrate your ESCs. if you are not sure what feedback you should get to indicate that the calibration was successful it could be that one didnt join the calibration routine with the others !I would suggest not to try any epxeriments and do every ESC by itself and calibrate it with the receiver and throttle on your TX !

You know how much time and money went in it. This could be the beginning of a faulty esc, thus the end of your copter if you fly it ! One component badly soldered for example on the specific ESC and thats it !

Regards


Boris

 

[Giovanni59]

I hooked up the snake to all the ESCs and the other lead to the throttle input on the RX to just run the motors and nothing happens. I must have done the snake wrong and I am getting no signal to the motors this way. That means I did not calibrate the ESCs initially but my interpretation of your advice is I do not have to calibrate these ESCs.

I did some tests: I put the 14' props on, this was all happening with 15' props, and did about 50 starts. #1 failed 2 times, #2 -1 time , #3- 2 times, # 4- 1 time, # 5-0 times, #6-6 times. I switched #5 with #6 and did the same test. #1 failed 4 times, #2-1 time, #3- 1 time and the rest did not fail. So, this is getting bizarre. I am thinking maybe by switching them I just made a better connection at the bullets. Another member, Steve suggested I plug and unplug them several times. In light of that I unplugged all connectors, lightly rubbed fine 000 steel wool on the male end and also took a nail and gently pushed it it the center spreading the prongs a little to make a tighter fit. I did some more tests and a few motors fail occasionally but it is not as bad.

I also took all the props off and started about 50 times and all the motors started every time.

 

[BorisS]

I hooked up the snake to all the ESCs and the other lead to the throttle input on the RX to just run the motors and nothing happens. I must have done the snake wrong and I am getting no signal to the motors this way. That means I did not calibrate the ESCs initially but my interpretation of your advice is I do not have to calibrate these ESCs.

I did some tests: I put the 14' props on, this was all happening with 15' props, and did about 50 starts. #1 failed 2 times, #2 -1 time , #3- 2 times, # 4- 1 time, # 5-0 times, #6-6 times. I switched #5 with #6 and did the same test. #1 failed 4 times, #2-1 time, #3- 1 time and the rest did not fail. So, this is getting bizarre. I am thinking maybe by switching them I just made a better connection at the bullets. Another member, Steve suggested I plug and unplug them several times. In light of that I unplugged all connectors, lightly rubbed fine 000 steel wool on the male end and also took a nail and gently pushed it it the center spreading the prongs a little to make a tighter fit. I did some more tests and a few motors fail occasionally but it is not as bad.

I also took all the props off and started about 50 times and all the motors started every time.

I am starting to think that the startup voltage of the ESCs is to low for you motor propeller setup. I just had a similar situation with some ESC32s. Without the props on the motors started without any problems with the 14 inch tigers they were either not starting up or stuttering. With the ESC32 i can change the startup voltage, increased it and that changes the situation. So the approach that once they are running there shouldn't be any problems anymore doesn't seem to awkward anymore ! But those times were they don't start up and you already increased the throttle and they are squeaking around cant be good for the motors, thus wear and tear on your motors that doesn't have to happen. It also seems like that you cant change the startup voltage or startup up method with the simonk flashed ESCs !

I would say look for simonk thread in rcgroups and post your video and see if he can pinpoint it. He can for sure also tell you if you are hurting your motors or not !

Boris

 

[Giovanni59]

Motors have been starting up OK most of the time. I wanted to alert everyone to a great dealer. I bought my T-Motors from Christos in Greece. http://www.multicopter.gr/ Not only did I get a great price he always replies very quickly to any enquiries. Most recently I had one motor acting funny and he immediately sent me a replacement, even before I returned the faulty motor. Now, that's service. He also carries props, ESCs and a lot of other stuff. I highly recommend him.