What Is The Lifespan Of A Servo?

John Burrow

I am using 10 Pico Servos on my model railroad. These will spend up to 6 hours a day powered up, but not necessarily moving.

The movement is 'occasional' (maybe 10 times per hour). I use only a small percentage of the rotation (pulse 800 to 2000) approx. The servo has much more power than is needed to just to move a semaphore signal. I had planned to send pulses only when movement is required; pulsing is not required to hold position

But now I've run out of pins on my BS2P, so I'm considering using a Servo Controller (which I already have).·My understanding is that this will continually pulse the servos to hold position. If this is correct, so am I going to burn out or cause early failure of the servo due to the 6 hours a day usage? An alternative is to go to a BS2P40,·which will give me the extra pins, where I can pulse only when movement is required.

Thanks
John Burrow
San Diego



·

SRLM

I doubt that your servos will wear out without moving (or holding a load in place). From my understanding, it's the brushes that go, and those only wear when the motor is turning.

Leon

The pots are subject to wear, as well. They are typically cheap carbon film units and will probably fail before the motor brushes.

Leon

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Phil Pilgrim (PhiPi)

I wouldn't worry about the servos constantly being pulsed. As long as they are holding their position, the motors will receive little or no current.

-Phil

JasonDorie

Nearly all servos have a dead band which prevents movement if they're close enough to their current set point. The dead band in digital servos is typically much smaller, which is why they buzz so much compared to normal servos. If the servo isn't under load, it won't be required to move, and if it's not moving, it's not wearing any of the mechanical parts. You'll be fine.

You can easily verify this by comparing the current draw when not pulsed, pulsed, not moving, and moving. I'd expect the first three to have very similar current draw.

Jason