Alarme AIS

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On my AIS it is possible to turn off these alarms by setting the AIS in config mode (connect it to a lap top via USB and run the configuration utility software). Here you can set the parameter “ALR Sentence” to “OFF” and these alarms will not be displayed on the chartplotter.

The reason why these alarms are triggered when the vessel is stationary is that when the vessel has no movement, it has no COG or HDG.

ce qui veut dire:
sur mon AIS, il est possible de désactiver ces messages d'alarme en choissisant le mode de paramétrage (config mode). Il faut le connecter sur un pc via usb pour ça, et utiliser l'application dédiée (j'imagine qu'il parle du CD fourni avec l'ais) .
On peut à partir de là cocher le paramètre "ALR sentence" sur "off" et les messages dont tu parles ne seront alors plus affichés.

La raison pour laquelle ces messages sont affichés lorsque le bateau est immobile, c'est que lorsqu'il est immobile, par définition, l'ais ne dispose pas de données d'orientation (hdg) ou de mouvement (cog)...logique..

Per the supplied NMEA 0183 data capture, the AIS500 is not only reporting alarms related to the receiver/transmitter hardware (either within the AIS500 or VHF antenna) but also related to AIS500's GPS features (either within the AIS500 or the AIS500's GPS antenna). Should the VHF antenna w/extension be tested with a VSWR meter ( en.wikipedia.org[...]R_meter ) and it be determined that the antenna w/extension combination have a VSWR between 1.0:1 - 2.0:1, then the AIS500 should be serviced by Raymarine's Product Repair Center.

If 6 minutes or more have elapsed since the AIS500 was powered ON, and should the AIS500 alarm with No Valid SOG or COG, and the AIS500's GPS antenna have an unobstructed view of the skies overhead, then the AIS500's GPS antenna should be tested with a resistance meter. Resistance will be measured from the center conductor to the shield. After recording the resistance measurement, the probe which had been touching the center conductor will be moved to the shield and vice versa. A good antenna should have an approximate resistance 4.8 Mohms when measured in one configuration and an approximate resistance of 7.2 Mohms when measured in the other configuration. The difference between the two measured resistance readings should be no less than 2.0 Mohms. If less than 2.0 Mohms, then the AIS500's antenna will need to be replaced. If more than 2.0 Mohms, then the AIS500 should be serviced by Raymarine's Product Repair Center.