What is wrong with my quadcopter?

The Flying Boo

Junior Member
Cross-posted from "Batteries and Charging Systems"

Hi all,

I have received a Syma x5c quadcopter (used from a brother), he had purchased 4 extra batteries along with this quadcopter. The batteries are "3.7V 600mAh." Along with the batteries is a 4-in-1 charger that can be plugged in via USB or wall plug adapter.

After flying the other day, my quadcopter began to slow down. I landed in front of me and checked the battery, which was fine. I tried to take off again and the motor didn't work. The motor had been burnt out. I purchased 4 new motors that were made for this particular model of quad and replaced the burnt motor. This may be where the problem lies but I highly doubt it.

The day the quad had burnt out, I plugged the batteries into the wall (4 of them) and left for dinner (and some activities with the family). They charged for maybe 5-6 hours, when I returned home later. I unplugged them since all the indicators were off, and they were complete.

Yesterday, I repaired the quad and it flew just fine! The only problem was the battery indicator light on my controller started flashing immediately- with a freshly charged battery. The quad flew very well for maybe 30 seconds, and then without hesitation began flying around 5-10 feet off the ground. It was very slow to ascend (although the turning was perfectly OK) and was very lethargic to my throttle control.

My question is, is it possible they were overcharged? They were on the charger for longer than they needed to be, but according to other resources, I was told they should stop charging immediately when they reach their limit. Is it possible I messed something up on the inside when repairing the motor? I didn't move anything around, I spliced the motor onto the old motor wires. All 4 batteries that were charged on the charger do the same thing.

Thank you all for your help, in advanced. I much appreciate it.


EDIT:

I have tested each battery with a volt meter and each one reads about 4.1-4.2 volts, after a charge. The one thing I noticed, when I tested each individual motor, was that although the average was around 3.7 volts, the voltage fluctuated to around 1.8 and just kept changing, like it was getting less power than what it needed to run at full power.

When I ran it, I could hear each motor changing pitch as it spun. Indicating to me, atleast, that it was not receiving enough power and changed pitch due to that.

I don't know much but it could be the motherboard of the quad, or the batteries are severely damaged and just don't like me

OR It could be the new motor that I just added to it. The new motor was meant for this model but it's possible I have a faulty motor.
 

Julez

WOT and going nowhere
You should measure the batteries under load. If you're discharging the batteries too far, or if you leave them on the charger and overcharge them, they may read 4.2 volts just sitting around but they will sag heavily under load. Most all batteries will read and maintain 4.2 vpc after being fully charged, but poor packs or packs that have not been taken care of properly will deliver very poor performance and will not last for many cycles before sagging.
 

razor02097

Rogue Drone Pilot
It is likely not your batteries... I have gone through the exact same thing. I wore out a set of motors where one motor would quit working intermittently. I ordered a set of motors from Amazon. It flew great for half a dozen times but started exhibiting issues such as overheating motors and lethargic performance. Since the X5C is a toy grade quad I've pretty much shelved it. I'm sure getting a set of good quality motors is the answer but I don't have the time or patience to order more motors.

Hope that helps you and I hope you find the issue.
 

trevoof

Member
Have you tried spinning each of the props to see if any of them get stuck? Perhaps there is some stickiness to one/some/all of the prop/gears causing the first motor to burn out and drawing an unsual amount of current.

Sometimes just simply taking a toothbrush to the gears can help.

https://www.youtube.com/watch?v=LzzD3BPVvH0&list=PLVZhhqqnkOnD6pxrx8yN1jdnrWPgoP10O&index=6

Hope you enjoy the X5C, that was my first RC aircarft, I had tonnes of fun with it. While I've moved on to more DIY planes and multirotors after discovering flitetest, I still fly it occasionally. More recently, I converted it to an indoor FPV ship as per Alex Grieve video.