Encoder - Counting up and down / reverse or invert ch A & B without changing the wiring.

[Graham Witkowski]

Hi 

 

I have written a programme to control a small rewinding machine, the machine run both CW & CCW.  I have the counter working, when it counts up the screen output in fine, if you run the encoder backwards the count will  go down, but once it reaches 0 and attempts to go into a minus the display ##########. The number is in -40 something millions.  Does this need a scaling factor?

 

The other issue I have is that sometime the  roll unwinds in the opposite direction and the encoder counts into a minus.  Is there a way to switch the input within the ladder? So the count is always positive?

Sorry if this is vague . Program attached

Final Vers 1.3 180823 no over temp 305dc.vlp

[kratmel]

If you use both direction for only positive count - no quadrature encoder signal needed (Shaft encoder must be changed to High Speed Counter) .

You can use High Speed Counter for encoder (run only to positive) without any changes in wiring.

Try to test this option and make some correction in math.

[Graham Witkowski]

On 9/12/2023 at 12:00 AM, kratmel said:

If you use both direction for only positive count - no quadrature encoder signal needed (Shaft encoder must be changed to High Speed Counter) .

You can use High Speed Counter for encoder (run only to positive) without any changes in wiring.

Try to test this option and make some correction in math.

I have not tried that yet.  The machines needs to be able to run in reverse to get the material passing under the encoder to stop in the right place, if it over runs.  HSC counts positive in both directions it wouldn't allow for error correction.