Question: How and where do you wire a REX?

Answer: The case inputs are correlated to each door. Case input 1 is door 1 case input 2 is door 2.

Note:  When Using a REX (or device to shunt the door contact) you will need to move the Fire Alarm input to case 3 or 4, since the Fire Alarm Relay is defualted to case input 1.