Servo burnout protection

Using a servo maestro and just lost my second servo due to it stalling (a loose bolt in the mechanism it was moving) and (I’m guessing) burning out? Do servos normally burn out when stalled and if so how can I protect against this? Besides not having loose bolts that is… thanks

Any motor will burn out if it’s overheated. Hobby servos generally have no protection against this, as such protection costs money and servos compete on price and specs.

I can think of at least three ways to add some protection:

  1. Add a temperature sensor to the servo. Perhaps drill a small hole and poke a thermistor into the casing. When this reads higher than, say, 60 degrees centigrade, cut off power to the servo.

  2. Add a current sensor in line with the power wire to the servo. When the servo has pulled more than, say, half its stall torque for more than, say, 0.25 seconds, cut power.

  3. Add a slow-blow fuse rated for just below the stall current of the servo to the circuit.

thanks jwatte…have several servos and limited space/patience so I was hoping there might be a controller or servo with a protection method. I guess the controller cannot really tell if the servo is not reaching its intended position- seems quite a drawback for such a great device.

Current, temperature, and load monitoring is a feature of higher-end servos. A controller would then read that data back from the servo itself.
Here’s an example: … /mx-64.htm
Expect to pay about $300 each.

Pololu has current sensor circuits. If you have an analog input on your controller, you might be able to use one of those to detect stall.
Try the ACS714: