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Buerste Buerste is offline
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Default Rotation detection?


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On Jul 6, 8:05 am, "Buerste" wrote:
Imagine a simple fractional hp DC gearmotor with a torque limiter or
torque
limiting clutch that powers a small machine at 60 or so RPM. Lets say the
machine jams and the torque limiting device kicks out. How can I cheaply,
easily sense this condition and turn off the motor?

You could put a photo sensor on the gear motor and the part of the
machine that stops turning when the terque limiter kicks out. Use
these to set and reset a flipflop. Integrate the output of the
flipflop. When the torque limiter kicks out the reset would no longer
occur, and the voltage from the integrator will go to high. Use this
to turn off the motor.
Dan
Good idea.