Eddy current drive

[Bill Watt]

If the feedback on an eddy current drive is wired backwards, what would happen to the motor? Would it speed up, slow down ? (This is a sample c of q question)

[neil seidner]

Bill: I am not familiar with the term "eddy current drive", is this something like a current transformer located in a motor circuit?

[electric-ed]

It is a type of magnetic clutch, that usually incorporates a range of speed control.

The feedback signal tells the control unit how fast (rpm) the output shaft is turning.

For example, with the unit running at a steady speed, the "setpoint" signal and the feedback signal would be equal- 0 difference signal.

Let's say the operator changes the setpoint for a higher speed. The control electronics compares the setpoint signal (now higher) to the feedback signal, and generates a difference signal, which is amplified and sent to the magnetic field unit to speed up the output shaft. The output shaft speeds up until the feedback signal is equal to the setpoint signal again.

I'm not sure what the correct answer would be. It would depend on the chuices given.

Ed

[neil seidner]

Thanks for the information Ed.