Propellers spin the drone cuts out

[sensational badger]

Hi All,
I'm a noob to quadcopters/drones and dont really know where to start when problem solving.
I have a Syma X5SW-1 and have managed just one flight. The day after this success i powered it up again pushed the accelerater forward to find the propellers would spin for about a second then the drone just dies. I have multiple batteries and all are fully charged.

Thanks in advance for any help.

 

[cranialrectosis]

Welcome to the FT forums.

Please don't cross post.
http://forum.flitetest.com/showthread.php?37234-Propellers-spin-then-the-drone-cuts-out

Someone will answer your thread not realizing someone else has already answered it. I think you may have your best luck in the multirotors section. Any of our mods will be happy to move your threads but please delete one of them.

Lipos are funny in that they can't be discharged under 3 volts. When a copter's ESCs detect a low voltage situation they shut down to avoid damaging the battery. What you are describing sounds to me like under charged lipos or lipos with too low a C rating. If the C rating is too low the lipo can't provide power fast enough and you cause a voltage sag under load.

What is the voltage output on your lipos and what is your C rating?

 

[sensational badger]

Thanks for the reply. Sorry, how do i delete the post?

The voltage is 3.7 - C rating is 25.

Regards

 

[cranialrectosis]

I would PM a mod. CraftyDan or Balu are on and may answer.

3.7v is correct for these and the copter isn't very heavy. 20C is very slow for a racer but for a Zyma should be fine.

Does the copter shut down during flight or only when sitting on the ground?

Does the copter shut down hard (kill all power) OR do the rotors slow to a stop causing the copter to fall but not at full speed?

 

[sensational badger]

I would PM a mod. CraftyDan or Balu are on and may answer.

3.7v is correct for these and the copter isn't very heavy. 20C is very slow for a racer but for a Zyma should be fine.

Does the copter shut down during flight or only when sitting on the ground?

Does the copter shut down hard (kill all power) OR do the rotors slow to a stop causing the copter to fall but not at full speed?

The copter doesn't take off at the moment. when the accelerator is pushed to attempt take off, the props spin then the copter shuts down hard.

 

[bazsound]

I have a symya x7? that usually happens when the batteries are low. Are you sure that your batteries are charging. 3.7v is the nominal voltage. at a full charge your batteries should be 4.2v

 

[cranialrectosis]

I have a symya x7? that usually happens when the batteries are low. Are you sure that your batteries are charging. 3.7v is the nominal voltage. at a full charge your batteries should be 4.2v

My mistake. 3.7 is the nominal charge. Fully charged you should be at 4.2 as bazsound has suggested. My copters will fly at 3.7 per cell but i am running 75c.

I agree with bazsound. I think the batteries are low.

 

[degazon]

I have the same problem when I arm motors spin perfect until I start raising the throttle quad stops. But when hold it in my hands (don't do this) then arm and throttle all the way it doesn't stop.. place it down same problem... help beginner pilot