Timer operates on 12 or 24volts DC.
Just connect to the unit and the timer will automatically adjust to the supply voltage.
Ideal to monitor the opening of a fire or emergency exit door.
Modes A, C and D have an additional feature - if the AUTO link is fitted the relay will reset after 20 seconds.
Inputs to both TRIG and RESET can be HIGH or LOW selected by Jumper link (in simple terms the means that it can be triggered and reset by connecting the inputs 12v or 0v)