Designed to give an audible and visual indication if a door is opened, such as a fire exit door or security cage. These units have one green LED, one red LED, a built-in key-operated switch and an internal sounder.

There is an alarm relay output, which can be connected to a conventional alarm control panel. This output is shunted when the key switch is turned. It also has an additional relay output, which operates whilst the unit is shunted, to enable remote monitoring of the unit.

The DA343 range is available common- or random-keyed and with or without audible shunt indication.

Typical uses include fire exit monitoring; with 12V operation, these are also ideal for security cages.