This unit is completely assembled and tested. All you have to do connect the voltage source to power up the board. The voltage source can be either AC or DC, 8 (minimum) to 15 volts (maximum).
This board has two detection circuits and two relay outputs, allowing for control of two independent locations on the tracks. Transmitter 1 and Detector 1, energize (close) Relay K1 contacts.
Transmitter 2 and Detector 2, energize (close) Relay K2 contacts. These relay contacts will close for a predetermined amount of time in seconds when the train breaks the beam between the corresponding Transmitter and Detector assembly on the track.