Getting Frustrated

[hoveringal]

Equipment: Spektrum DX7 / Gaui 500X / Woo Kong Controller / Turnigy Plush 30amp ESC's / Scorpion 960kv motors / New 4000-40C battery.

Problem: At start up only 2 motors spin up - the other two wait till 40% throttle. Holding quad above my head at half stick, I switch from M to Attit and RPM increases quite a bit (why). On line Woo Kong software shows no throttle changes when flipping between modes. Screen on DX7 shows no throttle changes flippping between modes.
All trims / sub trims are at zero. All ESC's programmed.

Problem: Seems when I get low on throttle stick position motors shut down. I know specs said less than 10% but I dont think I am that low when they stop..

With prop's removed I isolated each motor and connected one at a time to receiver - they start up properly.
Quad flew OK with Gaui 18 amp esc's which were too small. What did I do wrong? Afraid to lift. Need some advice please....

 

[dolby]

I know you said the ESCs are programmed but did you set the throttle end points (calibrate)? If you need help with that let me know.


Also in atti mode it is using barro sensor with height hold, so the throttle is going to be way different than when in manual mode.

 

[KopterX]

When you switch modes is normal for motors change RPM when you hold it by hand. Throttle on ATTI or GPS modes has not to much relevance because is overridden by the autopilot.
The problem where only two motors start and the other 2 start at 40% throttle sounds like the ESCs of this motors are not properly configured. Switch places of the ESCs to different motor and see if the results. If the problem moves to another motors then is ESCs problem. If stays on the same motors then might be a wiring problem between receiver and WKM and make sure you don't have motors on outputs 7 and 8!

 

[hoveringal]

Dolby - I swear the ESC's are programmed exactly the same and I used a Turnigy programming card. I will take it all apart and repeat the process just incase. As far as throttle end points I think this may be an issue only because I have not played with that. According to the screen on the DX7 I have full travel. I set the throttle trim to center - should it be at bottom zero????? I can use some help please. I set the ESC's as follows:
Brake; Off
Battery Type: Ni-xx (using Li-Po but told to use this to prevent issues)
Cut Off Type: Soft
Cut Off Voltage: Low
Start Mode: Norm
Timing MOde: Mid
Li-Po Cells: Didnt set - didnt understand
Governor: Off

KopterX: Thank you for that info - what a relief. I just checked and dont have 7 & 8 outputs. All jumpers are going to the proper slots. Motors are turning in the correct direction. Typically does everyone's Quad motors start at the same time??

 

[KopterX]

Motors should start in the exact same time. It still seems like a ESC problem. Just try to move the ESC to other motors and see the result.

 

[dolby]

No Setting the throttle end points is not done in the TX or with the programming card. I guess I should have said ESC throttle calibration. Sorry for the confusion.

1. Take off props
2. Connect 1 ESC to the throttle port on your RX
3. Turn on TX and put throttle at 100%
4. Power up the ESC and you'll hear some beeps, once done put the throttle at 0% (dont wait too long otherwise you'll go into programming mode) and you'll hear a few more beeps.
5. Now your ESC knows the throttle range of your tx.
6. repeat for each ESC.
7. Connect things back up normally and all motors should spin up at the same time.

The ESC needs to know the throttle range of your TX. This should be done any time you change a RX or switch to a different radio.

(Consult manual for beep codes concerning throttle calibration, not all the same)

 

[hoveringal]

OK... Just re-programmed each ESC by going thru each option one by one. Also changed battery type to Li-Po. All good. Then connected each ESC one at a time to the throttle port on the rcvr and followed Dolby's steps. Removed the camera landing gear system, charged a good battery and went outside.. Three motors were fine at idle up but one was lagging till I punched it and she jumped up and hovered. It tried to dip once real hard and not sure why or if it was the slow motor (was screamming too loudly) - need to check gains again. Hovered for about 8 minutes at various altitudes and modes (except M). Seems fine. Yaw was positive and only needed a few clicks of trim to lock in steady.. Temp on ESC's was between 109-114 and temp's on motors were between 115-120. Outside air temp is 101 degrees too.. I will dial down the gains a notch or two and do several more tests.. I really apprecaite you guys taking the time to help me.. It made a difference..

 

[Ghostrider]

Normally you want the battery type to be set to ni-xx not Li-Po. Most ESC's will try to protect the Li-Po's from going too low on voltage and will reduce power, pulse or shut off the motor when it reaches that point. That is where the other setting on the number of cells would come in. You don't want this on a multirotor since it will likely cause a crash. Better check this before you fly again.

 

[ksrimoungchanh]

I had something similar everytime I start too. I found that if I was in ATTI or GPS, the autopilot was sensing one site was lower then the other side when I started the motor. I tested it by placing it on a flat board and put a brick under one side and started motor and tested power up to 20% or so and shutdown. I then moved the brick under the other sides and did the power on again.. doing the test.. I found that the side the bride was under, would not spin up.

That was just my "caveman" test to make sure it was not consistent with just the original 2 motors or ESC.. etc... I can duplicate that each time so I am not that worried since it does fly and hover..

I normally power up on ATTI most of the time though..

 

[mailman35]

check the idle setting. i had this happen on my f450 using stock dji esc's, if i drop the timing by a notch then only 2 props spin, if i leave it in the middle everything works.

 

[hoveringal]

Great Info - thanks everyone. I think I will re-program the ESC's back to Ni-Cad rather than Li-Po.
My Gains are:
Pitch & Roll = 105
Yaw = 185
Vertical = 105
Attitude gain = 105 (Pitch & Roll)
Charging up a battery this morning for another test.. All motors starting spinning at idle up except # 2. I can get into a 3 foot hoover and suddenly it tries to dip the front left down but recovers. Almost looks like an oscillation?? I will drop the gains to 90% and see if improves. All trims, end points and expo's are centered or off. Travels on the computer screen look perfect. Blades going right direction. Im lost..

 

[hoveringal]

Well darn thing still acting up - can acheive 3 foot stable hoover then get hit with these left front nose dips. (motor #2). It recovers but something is wrong.. Tried lowering gains to 90%. May have helped tiny bit but dipping still present. I did notice motor # 2 was last to start up and looked like it tried to spin opposite way before spooling up. Is this a sign of anything? The Turnigy Plush ESC's did not have a color code but rather were numbered. Could this be an area of concern?

 

[makrospecardu]

Hi all
I've the same problem when I upgraded to FW5.12 from FW5.02, motors 3&4 turn very slowly on CSC. When I downgraded back to FW5.02 all motors start up at the same time. In the new firmware 5.12, there's a new menu "motor idle speed" under motor mix. Increase motor idle speed to High and this solved the problem and all motors started up at the same time under FW5.12! Programing my esc to motor @ low did not help but the later solves this problem. I've yet to fly with the new FW as I've just solved the motors not starting @ the same time after CSC. I'm flying a quad with Turnigy 30amp escs.

Cheers