Dumb question

Jrk wiring for simple speed control?? I have wired it for positional but for some reason I can’t seem to get it to do variable speed control…can somebody help me out here? Thanks!


The feedback signal from your tachometer should be connected to the Feedback pin (FB) on the jrk. You can find more information about this pin and using the jrk in Frequency/tachometer mode in the jrk user’s guide. If you are still having problems, you could post a diagram of your proposed connections, and I would be happy to take a look.

- Grant

Thanks grant will do if it doesn’t work…so tach motors will work with jrk not encoders??

In frequency/tachometer feedback mode, the jrk reads the frequency of a digital signal to determine the speed. If you have a quadrature encoder, you could use one of the channels as tachometer feedback.

- Grant

Grant one more question…is there a way to limit the motion of the motor in speed control mode?? example::: thinking of using motor to zoom a lens that has mechanical stops…how can I make a limit to stop motor when lens hits its stop??

The jrk does not directly support limit switches or something that would work in a similar manner. You could probably accomplish what you are describing by adding a microcontroller. The microcontroller would read some sort of sensor that would tell it when your lens hits its mechanical stops and command the jrk appropriately.

- Grant

Thanks Grant let me look into that.