Sperry Marine NAVIKNOT 600 SD, Operation, Installation And Service Manual

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056353/J NAVIKNOT 600 SD
3-26 Serial Data Alert Management
3.6 Serial Data Alert Management
Alert Handling (ALR/ACK)
NAVIKNOT complies with the statutory requirements regarding a serial
interface for the alert management (alert presentation and acknowledge-
ment) by a Central Alert Management System (CAM) following IEC
61162 (NMEA 0183) and MSC.302(87) (BAMS).
The NAVIKNOT 600 SD system supports the external alarm handling
using the $--ALR (set alert state) and $--ACK (acknowledge alert) sen-
tences according to IEC 61162 (NMEA 0183).
If transmission of the $--ALR sentence is enabled, the active alerts may
be displayed at an external alert handling device or may be recorded by
a VDR. If reception of the $--ACK sentence is enabled, pending alerts
may be acknowledged from the external alert handling device.
The $--ALR and $--ACK sentences are implemented as follows:
• When no alert conditions are present, the NAVIKNOT 600 SD trans-
mits a “no alerts” message as recommended per IEC 80/520/INF,
once per second. This is an $--ALR sentence with null fields for the
alarm code and description.
• When the NAVIKNOT 600 SD raises an alert, an $--ALR sentence,
containing the corresponding alert number and description text is
transmitted once per second. The alert will be marked as “active”
and “not acknowledged”.
In case of multiple alerts, the corresponding $--ALR sentences are
transmitted in turn, one sentence per second.
• If a pending alert is acknowledged (locally or through an $--ACK sen-
tence), the NAVIKNOT 600 SD marks the respective $--ALF sentence
as “acknowledged”.
• When an alert condition clears and the operator has not acknowl-
edged the alert, the NAVIKNOT 600 SD transmits the respective $--
ALR sentence with status „rectified“ and „unacknowledged“.
When an alert condition clears and the operator has acknowledged
the alert, the NAVIKNOT 600 SD transmits the respective $--ALR sen-
tence three times with status „acknowledged“. Then, the device
stops transmitting the sentence.