Servo Motors burned up on build

Candres

New member
Hello, my son and I are building our first plane (Simple Cub). We are having issues with the servo motors (ES08AII). We plugged them into the receiver (an AR620), and let them zero. Then we mounted them in the plane and were testing the controls when they started moving back and forth aggressively for 5-6 seconds and then quit. We were no longer able to control them (no movement). We had a couple extra, and tried again, being careful to zero them before hooking up the control rod and gluing them in (to zero we plugged them into the receiver with no arm attached and powered them up and left them find zero. then attached the arm without moving the motor). Both worked initially, but then started moving aggressively and appeared to burn out. The only other thing I noticed is it seemed on the last one It started acting up when I moved the receiver around. I am wondering if the receiver was loosing the feedback signal (or it was erratic) and that initiated the damage. I ordered some new servo motors and a new receiver, but if anyone has any insight I would appreciate it. I'd rather not end up with more damaged servo motors. Thanks!
 

GrizWiz

Elite member
Hello, my son and I are building our first plane (Simple Cub). We are having issues with the servo motors (ES08AII). We plugged them into the receiver (an AR620), and let them zero. Then we mounted them in the plane and were testing the controls when they started moving back and forth aggressively for 5-6 seconds and then quit. We were no longer able to control them (no movement). We had a couple extra, and tried again, being careful to zero them before hooking up the control rod and gluing them in (to zero we plugged them into the receiver with no arm attached and powered them up and left them find zero. then attached the arm without moving the motor). Both worked initially, but then started moving aggressively and appeared to burn out. The only other thing I noticed is it seemed on the last one It started acting up when I moved the receiver around. I am wondering if the receiver was loosing the feedback signal (or it was erratic) and that initiated the damage. I ordered some new servo motors and a new receiver, but if anyone has any insight I would appreciate it. I'd rather not end up with more damaged servo motors. Thanks!
Is you receiver putting out 5 volts? You may have also put the servos in upside-down. The yellow or white wire should be up! Can you post a picture of you electronics setup?
 

quorneng

Master member
Well the first thing is after several servos failing something is obviously wrong with your set up so do not try any more until the problem is identified.
As Grizwiz says a picture of the set up would be a great help.
How is power supplied to the receiver? A BEC via the ESC or a separate battery.
Just how free moving are the control linkages?
It may be necessary to set up the power supply, receiver and a servo 'stand alone on the bench' controlled by the transmitter to check it functions normally.
 

GrizWiz

Elite member
I agree. Have you got a servo tester?
I believe Josh goes over how to use it in the build video
 

Bricks

Master member
As mentioned above pictures would help, are you sure the receiver and transmitter are bound which transmitter are you using? What are you using for an ESC , how many servos and motor? Have you tried controlling all the servos with out hooking them up to any control surfaces and do they then continue to work? If yes then your control surfaces are to stiff and may be kicking out the BEC. After unhooking the battery letting everything sit and cool down, did you try and reconnect the battery to see if anything works again without the control surfaces connected...if so then this leads too stiff of control surfaces or a very weak ESC.