We don't have the Zeus3, but I think it will be similar to our Zeus2.
For this it works as follows:
You can define alarm conditions, e. g.
wind speed or direction change, AIS alerts and
Radar guard zone alerts.
Alarms are displayed on
screen and the internal buzzer starts beeping.
When enabled, the external alarm output is activated whenever any alarm condition is raised. Unfortunately it is not possible to limit which alarms to propagate, so it's all or nothing. We have wired the external alarm to a loud siren. There's a switch in series to the siren so it is possible to enable to disable the external alarm easily.
We like to program AIS and
Radar proximity alerts for night watches on passages. The person on watch is easily alerted with the internal Zeus2 beeper, and it's quiet enough not to wake up the person off watch. The downside is that this pretty much rules out usage of the external siren. Due to this limitation we very seldom use it.
BTW, I think this thread should be moved to the general
Electronics forum.