Furuno FMD-3200 Operator's Manual page 368

25. ALERT MANAGEMENT SYSTEM (option)
HBT sentence
Both external equipment and the AMS output the HBT sentence periodically to confirm
normal operation between each other. The sentence is output regardless of whether
an alert is generated or not.
When the HBT sentence is not received within the interval set, an appropriate alert is
generated which announces equipment trouble (power off, etc.). The AMS generates
the alert "Loss of system communication".
When an alert is generated...
When an alert condition is found at an external equipment, the equipment sends the
ALF sentence to the AMS.
The ALF sentence contains Alert ID, Alert Priority, Alert Category, ACK/Silence, and
other information. The AMS generates an alert based on the ALF sentence and sends
it to the external equipment to acknowledge receipt of the alert.
Alert
condition
Equipment
Equipment
Generate
alert
Periodic transmission
External equipment periodically (30 s or less) send alert status to the AMS using the
ALC sentence.
If the ALC sentence contains an alert, the AMS sends the ACN sentence to the exter-
nal equipment to request re-notification.
Alert(s)
activated
25-6
External External
Equipment Equipment
External External
External External
Equipment Equipment
HBT
HBT
ALF
AMS
ALC
AMS
(ACN)
AMS
Generate alert
based on ALF
sentence
Confirm no
omission of
sentences