[Al Skierkiewicz]

The light sensor outputs will provide a closure to power common or will remain open circuit. The digital side car digital inputs have pullup resistors to +5 volts. So when the sensor is open, the output will be pulled up to 5 volts through the DSC and when the sensor is closed, the output will be pulled down zero volts through the NPN transistor in the sensor. No other components are needed. The 12 volt input is required to power the emitter and other internal electronics.