CC3D Start Up Problem
« on: June 26, 2017, 09:56:28 pm »
Can anyone tell me why my quad will not lift off ? Yaw right-motors spins. when i apply throttle the motors spin up then spin down after the quad lifts off about a foot off the ground. at that point if I apply throttle again the motors spin in different speeds. All 4 motors are confused. If i disarm the rearm, i get the same result. motors spin up then spin down when throttle is applied. ive calibrated the motors  using the manual method and using the GUI. All motors are within 3 on the neutral side and all are maxed out at 1900. this only happens with the props on.  if i remove the props and arm the motors respond all the way through the throttle movement. 
Any ideas ?


dji flamewheel450
cc3d
simonk 30a esc
10" generic props
« Last Edit: June 26, 2017, 10:00:23 pm by bttmdwlr »

Re: CC3D Start Up Problem
« Reply #1 on: June 27, 2017, 07:43:09 am »
My first guess would be a weak battery.  Fly it with a LIPO alarm to see if the voltage drops under load.

Re: CC3D Start Up Problem
« Reply #2 on: June 27, 2017, 10:37:49 pm »
Right,that makes sense. But unless my balanced charger lies to me............. I take a freshly charged 11.1v 2200a cell or my 2700a cell (12.45v and 12.39v) the same results. But when i remove the props nothing unusual occurs. Motors spin up and run with no problem. As soon as load is placed upon the motors I lose them.
thankx for the lead. i will continue to attempt a fix and will report.

One thing: BLADE QX350 USERS: Microheli Precision CNC Aluminum Prop Adapter set (RED) - BLADE 350 QX. check the screw set for PROPER LENGTH. the set i bought were too long and the screws chewed the tops of the windings off and now I have 2 blade motors that dont work. check the adapter screw length

Re: CC3D Start Up Problem
« Reply #3 on: June 28, 2017, 07:18:58 am »
Do they stop suddenly with a jerk or smoothly slow down?

Do you hear ESC startup tunes when you plug the battery in?  Do you hear this tune when the motors stop also?

If a jerk, some motor / ESC combinations don't work well together, and and even worse when you try to change RPM quickly.

If smoothly, does something somewhere get hot?

You could test (very carefully !!!!!!!) with Output page, with props on.  Use right column to link all motors together.  I suggest that you test first with props off, to get to know the sliders.  Once you link all and click a slider, you can control all motors with keyboard left-right arrows.  This would be safer if you could strap the quad down somehow and with careful certainty.

Re: CC3D Start Up Problem
« Reply #4 on: June 29, 2017, 03:44:55 am »
Thanks Ciff(which ever one you are--lol) thats the method i used to calibrate the esc when we first started this ordeal. they die like power cut off die. do dont experience any jerking motions,like when a screw is too long and your core is shorting out.  really has me trippin'. Went so far as to check the rotor and shaft for e clips as the rotor
without a clip may fly off ?  but thats pretty extreme cause if they even started to separate,well.............
today switched the generic 2212 1000kv motors for 4 x Blade 7804's from a 350 thats parts.  same thing...oh well

thanks cliff(i still dont know which one you are   lol)

Re: CC3D Start Up Problem
« Reply #5 on: June 29, 2017, 08:02:01 pm »
Let it sit a while (say a minute) after battery plug in to run FligthTime up.  Look at FlightTime (time since FC was powered on) before and after the drop.  If you see that the FlightTime looks like it was reset, then your FC is resetting in flight and determine why (bad solder joint?).

Re: CC3D Start Up Problem
« Reply #6 on: June 29, 2017, 08:33:57 pm »
More things to be aware of:
- LIPOs are 4.2v per cell when charged.  That 11.1v pack is actually discharged if it is 11.1v.
- If you are running stock ESCs (not SimonK or BLHeli) then you must disable (or set to Nicad) the LowVoltageCutoff in the ESC setup.

Re: CC3D Start Up Problem
« Reply #7 on: June 30, 2017, 11:36:41 am »
my gawd. Youve impressed me with the brilliance you employ.  ill do it and report for sure.  Im new at this and that battery voltage/amp thing has me confused to say the least. a 11.1 v is discharged at 12.5v ? must be if theyre four point  a cell.

thankx again cliff.

Mateusz

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Re: CC3D Start Up Problem
« Reply #8 on: June 30, 2017, 11:55:14 am »
my gawd. Youve impressed me with the brilliance you employ.  ill do it and report for sure.  Im new at this and that battery voltage/amp thing has me confused to say the least. a 11.1 v is discharged at 12.5v ? must be if theyre four point  a cell.

thankx again cliff.

Single cell battery voltage is 3.8 for storage (how you buy it and store it) and 4.2 for fully charged.
  • 1S: 1 * 4.2 =  4.2 and 1 * 3.8 = 3.8
  • ...
  • 3S: 3 * 4.2 = 12.6 and 3 * 3.8 = 11.39
  • 4S: 3 * 4.2 =  16.8 and 4 * 3.8 = 15.2
  • ...

Unrelated to question other parameters of battery are:
  • Cappacity: [mAh]
  • Continuous discharge rate: [C]
  • Burst discharge rate: [C]
  • Charge rate: [C]

Usually 1C of charging rate for 1000mAh battery = 1A of current to charge battery.
So 400mAh battery if you want to charge at 1C that would be 0.4A.

I always charge batteries with capacity > 1000mag at 1-2C its slow but battery lasts longer, and batteries at capacity < 1000mAh with 1C.