Below shows the detailed schematic of the opto-isolated limit, home, and general-purpose digital inputs. All opto-isolated digital inputs are NPN type.

NPN Digital Input


The opto-supply must be connected to at least +12VDC, but not exceed +48VDC, in order for the limit, home, and digital inputs to operate at maximum efficiency.

When a digital input is pulled to ground, current will flow from the opto-supply to ground, and the optocoupler will then power on and activate the corresponding input(s).

To deactivate the input, a digital input should be left unconnected or switched back to the opto-supply. This will stop current from flowing through the optocoupler to ground.