What it is used for?

Electronic device connected to a PC computer to warn that the computer or the application or the printer is not working. It listens to the heartbeat from the computer.


Physical characteristics

Electronic circuit in easy to install box
Built in terminal bloc for easy wire connection
Led display: Green for Power and Red for Alarm
Powerful buzzer for alarm warning
Cable with DB9 connector for computer serial port connection and connector to mate with ongoing serial cable
Power fed from 12v DC alarm panel or by other 12v DC source
Optional signal for alarm panel




Conditions to trigger an alarm

The Watch Dog circuit is triggered by the absence of the Heartbeat if one the following events happens:

1. The computer program ceases to send the Heartbeat for a period of approximately 90 seconds.

2. A breakdown of the computer equipment.

3. A power failure of the computer.

4. A power failure of the DC input for Watch Dog will not light the Red Warning led nor will it trigger the buzzer. However if a line runs to the alarm panel, the closing of the circuit will trigger an alarm at that point.