Sea-Bird Electronics SBE 38, User Manual

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Manual revision 013 Section 2: Description of SBE 38 SBE 38
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Section 2: Description of SBE 38
This section describes the functions and features of the SBE 38, including
specifications and dimensions.
System Description
Sophisticated A/D acquisition electronics, ultra-stable thermistor, and state-of-
the-art calibration provide the standards-level performance of an expensive
AC bridge and platinum thermometer at a small fraction of the cost. The
SBE 38 is unaffected by shock and vibration, has high accuracy and stability,
and is easy to use. It has a rugged, corrosion-proof, 10,500 meter (34,400 foot)
titanium pressure housing. Real-time temperature data is transmitted in ASCII
characters (in °C or raw counts) via an RS-232 or optional RS-485 serial
interface for display or logging by PC or data logger.
The SBE 38’s measurement range is -5 to +35 °C. Absolute accuracy is better
than 0.001 °C (1 mK) and resolution is approximately 0.00025 °C (0.25 mK).
Each sensor includes certification that demonstrates drift of less than 0.001 °C
(1 mK) during a six-month period.
Applications include calibration baths, oceanographic/aquatic research, and
environmental monitoring.
The SBE 38 operates in one of three ways:
• RS-232 (full duplex) with one SBE 38 connected to the interface
• RS-485 (half duplex) with one SBE 38 connected to the interface
• RS-485 (half duplex) with several RS-485 sensors sharing one pair
of wires
On power-up, the SBE 38 reads its EEPROM, which includes calibration
coefficients and other setup information. As programmed, the SBE 38 samples
and transmits temperature continuously, or waits for a command to begin
sampling. Note that for RS-485 applications with several sensors sharing one
pair of wires, the SBE 38 cannot sample continuously.
The SBE 38 is frequently integrated as a remote temperature sensor with one
of our thermosalinograph instruments (SBE 21 Thermosalinograph or SBE 45
MicroTSG), to provide accurate sea surface temperature. See the manuals for
those instruments for integration information.
The SBE 38 is supplied with a powerful Win 2000/XP software package,
SEASOFT V2, which includes:
• SEATERM terminal program for easy communication.
• Seasave V7 real-time data acquisition and SBE Data Processing
post-processing programs –Seasave V7 and SBE Data Processing can be
used to view and process the entire data stream, including data from the
SBE 38, when the SBE 38 is integrated with one of the following -
- SBE 21 or 45 thermosalinograph;
- SBE 16 plus , 16 plus V2, or 16 plus -IM V2 SEACAT C-T Recorder; or
SBE 19
plus
V2 SEACAT CTD Profiler.
Notes:
• Help files provide detailed
information on the software.
• Separate software manuals on
CD-ROM contain detailed
information on Seasave V7 and
SBE Data Processing.
• Sea-Bird supplies the current
version of our software when you
purchase an instrument. As software
revisions occur, we post the revised
software on our FTP site. See our
website (www.seabird.com) for the
latest software version number, a
description of the software changes,
and instructions for downloading the
software from the FTP site.
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