Hobb7t:
Im missing some serious info about opto-couplers.
An opto coupler is a LED with a photo transistor in one package.
The transistor switches on/off depending on the light output of the LED.
There is no electrical connection between the two, just light.
They are used in circuits where you don't want an electrical connection between two separate circuits.
For safety, or to break ground loops, or to isolate 'dirty' circuits (motors) from 'cleaner' circuits (Arduino).
In your case, you might or might not need them.
Post a full diagram.
Leo..