Nexus RACE BOX, Инструкция по установке и эксплуатации

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RaceBox English
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4.4.1 Polar File
To do this, the Race Box needs a “polar file.” A polar file is a list of boat speeds and
wind angles. These files can be generated by computer programs which know about a
boats hull shape, weight, rig dimensions and other factors. If you want to purchase a
polar file for your boat, contact US Sailing. There are also a lot of polar tables on
www.blur.se. Or, a polar file can be created by recording data about how a boat actually
performs at a variety of wind speeds and angles. The Race Box logs are a great way to
record this information.
Your polar file must be put on the Race Box SD card. As mentioned earlier, the polar
file should be in standard Nexus polar file format. The file name must end in .NXP and
the file must be placed on to the SD card so it can be read by the Race Box at startup.
If you don't have a polar table or just prefer not to use one, then set the following
configuration option in the rp4n.cfg file like this:
USE_POLAR_TABLE = N
When this is set, the Race Box will not try to load the polar file at startup, so no polar file
is necessary on the SD card. Also, it will not be able to calculate PBS or TBS
information.
TBS and PBS are both calculated by checking the true wind speed (TWS) and your
current true wind angle (TWA), and then applying this information to your polar table. Of
course, this information varies as the wind speed and your sailing angle does.
The data in polar files also needs to be adjusted for the height of your wind transducer
above the water surface . Many people manually edit the data in their polar file, but this
is not necessary since the Race Box will compensate for transducer height. In order for
it to do this, the configuration file needs to be told the height of the transducer
above the
surface of the water , in feet. The proper line in the configuration file is:
WIND_XDUCER_HEIGHT=43
If you have already adjusted your polar file to compensate for your transducer height,
then set the height to 0, like this:
WIND_XDUCER_HEIGHT=0
4.4.2 Choosing Whether TBS or PBS is Sent to the Nexus Network
The Nexus instrument system has a data field called TBS, but this field can be used
either for target boat speed or polar boat speed. The Race Box configuration file
controls what information is sent to this field. This information is then published
throughout the Nexus network and all instrument features related to TBS can be used.
For example, all of the NX2 and NXR instruments have the ability to simply present the
value of the TBS filed, in knots, as a number. Also, the NX2 Wind Instrument can trim
on TBS. When the Wind Instrument is set up to do this, it has an indicator which raises