The central unit can handle up to 50 alarm points. The device contains a display with 8 red/green alphanumeric characters (character height 12mm) and 2 green function buttons. Red acknowledgment diode and green operation indication under a 2mm light guide in the lid. Buzzer with adjustable volume and input for control function (activation of “Receipt”). Outputs for buzzer, total alarm and error alarm. Press the lid: "Receipt". Connection takes place on a screw terminal with wire protection placed on a pluggable terminal board.