Jeppesen Nobeltec SSHS, Owner'S Manual

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Solid State Heading Sensor (SSHS) Owner’s Manual
12
If the SSHS receives variation information from the
NMEA 0183
interface, it will do the
following (see
Appendix A
for enabling or disabling NMEA 0183 sentences):
1. Transmit the Heading, Deviation & Variation (HDG) sentence, including the variation
field as seen from the RMC or VTG sentence over the NMEA 0183 interface if HDG is
enabled.
2. Transmit the Heading True (HDT) sentence using variation data from the RMC or VTG
sentence over the NMEA 0183 interface if HDT is enabled.
3. Transmit over the NMEA 2000 interface the Magnetic Variation PGN (127258) with the
Variation Source field value corresponding to the received NMEA 0183 variation data
from the RMC or VTG sentence. The PGN’s Variation Source field will be transmitted
with the lowest possible quality indicator, which is “Manual Entry”.
Variation Input via the NMEA 2000 Interface
Note:
Jeppesen Marine does not provide technical support for the NMEA 2000
interface as of this printing.
As shipped from the factory, the SSHS also automatically looks for variation data coming from
the NMEA 2000 interface. The SSHS accepts variation data from the Magnetic Variation PGN
(127258).
If the SSHS receives variation information from the NMEA 2000 interface, it will do the
following:
1. Transmit the Heading, Deviation & Variation (HDG) sentence, including the variation
field as seen from the Magnetic Variation PGN (127258) from the NMEA 2000 interface
if HDG is enabled (see
Appendix A
for enabling or disabling NMEA 0183 sentences).
2. Transmit the Heading True (HDT) sentence using variation data from the Magnetic
Variation PGN (127258) from the NMEA 2000 interface if HDG is enabled (see
Appendix A
for enabling or disabling NMEA 0183 sentences).
Variation Input via Manual Entry
If no other source of variation is available (i.e., neither the NMEA 0183 nor NMEA 2000
interface), the SSHS can be programmed with a fixed variation value for a given location (this
value can be found on most navigational charts).
If variation is manually entered into the SSHS, it will then do the following:
1. Transmit the Heading, Deviation & Variation (HDG) sentence including the variation
field as manually entered over the NMEA 0183 interface if HDG is enabled (see
Appendix A
for enabling or disabling NMEA 0183 sentences).