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• Naviom Electronics® specified cables are used.
Suppression ferrites
• Use data cables with pre-fitted or supplied with suppression ferrites. These are important for correct
EMC performance. If ferrites are supplied separately to the cables (i.e. not pre-fitted), you must fit
the supplied ferrites, using the supplied instructions.
• If a ferrite has to be removed for any purpose (e.g. installation or maintenance), it must be replaced
in the original position before the product is used.
• Where an installation requires multiple ferrites to be added to a cable, additional cable clips should
be used to prevent stress on the connectors due to the extra weight of the ferrites.
RF interference
Certain third-party external electrical equipment can cause Radio Frequency (RF) interference with
GPS, AIS or VHF devices if the external equipment is not adequately insulated and emits excessive
levels of electromagnetic interference (EMI).
Some common examples of such external equipment include LED spot or strip lights, and terrestrial
TV tuners.
To minimize interference from such equipment:
• Keep it as far away from GPS, AIS or VHF devices as possible.
• Ensure that any power cables for external equipment are not entangled with the power or data
cables for GPS, AIS or VHF devices.
• Consider fitting one or more high frequency suppression ferrites to the EMI-emitting device. The
ferrite(s) should be rated to be effective in the range 100 MHz to 2.5 GHz, and should be fitted to
the power cable and any other cables exiting the EMI-emitting device, as close as possible to the
position where the cable exits the device.
Compass safe distance
To prevent potential interference with the vessel's magnetic compasses, ensure an adequate distance
is maintained from the NAVIOM AIS.
When choosing a suitable location for the NAVIOM AIS you should aim to maintain the maximum
possible distance from any compasses. Typically this distance should be at least 1 m (3 ft) in all
directions.
However for some smaller vessels it may not be possible to locate the NAVIOM AIS this far away from
a compass. In this situation, when choosing the installation location, ensure that the compass is not
affected by the NAVIOM AIS when it is in a powered state.
Note: Where constraints on the installation prevent any of the above recommendations
,
always ensure the maximum possible separation between different items of electrical equipment,
to provide the best conditions for EMC performance throughout the installation
Summary of Contents for AIS
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