`
You have to silence the alarm to stop it sounding then press reset (note the buttons don't work until the key is turned or the code entered)
All the lights on the panel light upto & it should be silent & fault free....
If if goes straight back into alarm silence the alarm & go & check the device
If the worse comes to the worse remove you can disable devices from the panel, this will shown a disablement fault on all panels
Powering down addressable alarms is not a good idea, your much more likely to end up with more issues. than you started
Is this a ship ?