Manual revision 017
Section 2: Description of SBE 33
SBE 33
18
NMEA and Surface PAR
The SBE 33 includes a NMEA 0183 interface that permits NMEA data to be
merged with the CTD data. The SBE 33 is designed to decode messages that
are output from devices supporting NMEA 0183 protocol. Decoded NMEA
data can be appended to the end of the CTD data stream in the SBE 33 and
passed to the computer for storage and/or display with the CTD data (see
Appendix I: NMEA Device Message and Data Formats
). The Yellow
NMEA
Transmit
LED on the SBE 33 front panel flashes each time a NMEA message
is received (should be same rate at which your NMEA device is transmitting).
The SBE 33 appends the same NMEA message multiple times, until a new
message is decoded.
Example
: A NMEA device outputs its message once every 5 seconds. The
Yellow
NMEA Transmit
LED flashes every 5 seconds, and the same
message is appended to each scan of CTD data within that 5 seconds.
If NMEA position data is being added to the data stream, the SBE 33 also
allows for the addition of NMEA depth (for example, from a NMEA echo
sounder) to the data stream.
The SBE 33 can also acquire the 0 to 5 volt output of a Surface PAR sensor,
append it to the CTD data stream, and pass it to the computer for storage and/or
display with the CTD data. Seasave and SBE Data Processing support the
acquisition and display of data from the following sensors:
Satlantic (Sea-Bird Scientific) Surface PAR sensor (logarithmic or linear)
Biospherical (QSR-240, QCR-240, QSR-2200, or QCR-2200) Surface PAR
sensor
Notes:
If you are not sure which NMEA
messages your navigation device is
sending, see
Section 7:
Troubleshooting
for information on
viewing the raw NMEA message using
the SBE 33
’s diagnostic mode.
SBE 25: if the SBE 25 is integrated
with more than 4 auxiliary voltage
sensors, and the SBE 33 is appending
both NMEA and Surface PAR, you
must set the SBE 25 real-time output
rate to 4 scans/sec or less (see
SBE 25 manual for command details).
SBE 25
plus
: If the
SBE 33 is
appending both NMEA and Surface
PAR, you must slow down the real-
time output rate by setting
SetHistoricRate=0
(see the 25
plus
manual for command details).
SBE 49: Seasave (real-time data
acquisition software) 7.23.2 and later
supports acquisition of Biospherical
Surface PAR data.
Seasave (real-time data acquisition
software) 7.26.7 and later supports
acquisition of Satlantic Surface PAR
data.