SBE 38 User Manual
SBE 38 Digit al Oceanographic Thermometer
With RS-232 or optional RS-485 Interface
User’s Manual
Sea-Bird Electronics, Inc.
1808 136
Bellevue, Washington 98005 USA
Telephone: 425/643-9866
Fax: 425/643-9954
E-mail: seabird@seabird.com Manual Version #006, 03-14-03
Website: www.seabird.com Firmware Version 1.2 and later
th
Place NE
Limited Liability Statement
Extreme care should be exercised when using or servicing this equipment. It should be used or serviced
only by personnel with knowledge of and training in the use and maintenance of oceanographic
electronic equipment.
SEA-BIRD ELECTRONICS, INC. disclaims all product liability risks arising from the use or servicing
of this system. SEA-BIRD ELECTRONICS, INC. has no way of controlling the use of this equipment
or of choosing the personnel to operate it, and therefore cannot take steps to comply with laws
pertaining to product liability, including laws which impose a duty to warn the user of any dangers
involved in operating this equipment. Therefore, acceptance of this system by the customer shall be
conclusively deemed to include a covenant by the customer to defend, indemnify, and hold SEA-BIRD
ELECTRONICS, INC. harmless from all product liability claims arising from the use or servicing of
this system.
2
Table of Contents
Table of Contents
Section 1: Introduction....................................................................................4
About this Manual .............................................................................................4
How to Contact Sea-Bird...................................................................................4
Quick Start.........................................................................................................4
Unpacking SBE 38.............................................................................................5
Section 2: Description of SBE 38....................................................................6
System Description............................................................................................6
Specifications.....................................................................................................7
Dimensions and End Cap Connector.................................................................8
Baud Rate and Cable Length .............................................................................8
Section 3: Preparing SBE 38 for Deployment ...............................................9
Installing Software.............................................................................................9
Power and Communications Test ......................................................................9
Test Setup...................................................................................................9
Test...........................................................................................................10
Section 4: Deploying and Operating RS-232 SBE 38..................................13
Sampling Modes..............................................................................................13
Polled Sampling........................................................................................13
Continuous Sampling................................................................................14
Command Descriptions....................................................................................15
Data Output Formats........................................................................................17
Deployment......................................................................................................17
Recovery..........................................................................................................17
Section 5: Routine Maintenance and Calibration.......................................18
Corrosion Precautions......................................................................................18
Connector Mating and Maintenance................................................................18
Sensor Calibration............................................................................................19
Glossary..........................................................................................................20
Appendix I: Functional Description.............................................................21
Sensor Interface...............................................................................................21
Settings ............................................................................................................21
Appendix II: Electronics Disassembly/Reassembly....................................22
Appendix III: RS-485 Interface....................................................................23
Operation Description......................................................................................23
Command Descriptions....................................................................................24
RS-485 Commands...................................................................................24
All Other Commands................................................................................25
Data Output Formats........................................................................................25
Wiring..............................................................................................................26
Conversion of RS-232 to RS-485 or RS-485 to RS-232..................................26
Appendix IV: Command Summary.............................................................27
Appendix V: Replacement Parts ..................................................................28
Index................................................................................................................29
3
Section 1: Introduction
Section 1: Introduction
This section includes contact information, Quick Start procedure, and photos
of a standard SBE 38 shipment.
About this Manual
This manual is to be used with the SBE 38 Digital Oceanographic
Thermometer.
It is organized to guide the user from installation through operation and data
collection. We’ve included detailed specifications, command descriptions,
maintenance and calibration information, and helpful notes throughout
the manual.
Sea-Bird welcomes suggestions for new features and enhancements of our
products and/or documentation. Pl ease e-mail any comments or suggestions to
seabird@seabird.com.
How to Contact Sea-Bird
Quick Start
Sea-Bird Electronics, Inc.
1808 136
Bellevue, Washington 98005 USA
Telephone: 425-643-9866 Fax: 425-643-9954
E-mail: seabird@seabird.com Website: http://www.seabird.com
Business hours:
Monday-Friday, 0800 to 1700 Pacific Standard Time
Except from April to October, when we are on summer time
Follow these steps to get a Quick Start using the SBE 38 with a standard
RS-232 interface. The manual provides step-by-step details for performing
each task:
1. Test Power and Communications (see Section 3: Preparing SBE 38
2. Deploy the SBE 38 (see Section 4: Deploying an d Operating RS-232 SBE 38):
For an SBE 38 with optional RS-485 interface , see Appendix III: RS-485
Interface for details.
th
Place Northeast
(1600 to 0100 Universal Time)
(1500 to 0000 Universal Time)
for Deployment).
A. Establish setup parameters.
B. Use one of the following sequences to start sampling:
• If AUTORUN=N: GO to start sampling continuously now, or
TS or TH to take a single sample.
• If AUTORUN=Y: Apply power to start sampling
continuously now.
C. Deploy SBE 38.
4
Section 1: Introduction
Unpacking SBE 38
Shown below is a typical SBE 38 shipment.
I/O Cable with 9V battery snap
connector and 9V battery
User Manual
SBE 38 Digital
Oceanographic
Thermome ter
SBE 38
25-pin to 9-pin adapter
Software, and Electronic Copies of
Software Manuals and User Manual
5
Section 2: Description of SBE 38
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-ofthe-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 standard measurement range is -5 to +35 °C. An optional range of -5 to
+50 °C is available at slightly reduced accuracy and resolution. For the
standard range, 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
Notes:
• Sea-Bird also supplies a DOS
software package, SEASOFT-DOS,
which can be used with the SBE 38.
However, this manual only details
use of the Windows software with
the SBE 38.
• Help files provide detailed
information on the use of
SEATERM, SEASAVE, and SBE
Data Processing.
• Separate software manuals on
CD-ROM contain detailed
information on the setup and use of
SEASAVE, SBE Data Processing,
and SEASOFT-DOS.
those instruments for integration information.
The SBE 38 is supplied with a powerful Win 95/98/NT/2000/XP software
package, SEASOFT-Win32, which includes:
• SEATERM terminal program for easy communication.
• SEASAVE real-time data acquisition and SBE Data Processing
post-processing programs – When the SBE 38 is integrated with the
SBE 21 or 45 thermosalinograph, SEASAVE and SBE Data Processing
can be used to view and process the entire data stream, including data
from the SBE 38.
6
Section 2: Description of SBE 38
Specifications
Measurement
Range
Standard: -5 to +35 °C
Optional: -5 to +50 °C
Note:
If the SBE 38 is sampling data
and the voltage is less than
6.5 volts for 10 consecutive
scans, the SBE 38 halts sampling
and displays a low battery
indication in the data.
Initial Accuracy 1
Typical Stability
Resolution
Calibration
Response Time 2
Self-Heating
Error
RMS Noise
(at temperature
equivalent of 8.5 °C)
External Power
Materials
0.001 °C (1 mK)
0.001 °C (1 mK) in 6 months, certified
0.00025 °C (0.25 mK)
Standard: -1 to +32 °C
Optional: -1 to +50 °C (accuracy above
standard range is degraded to 0.003 degrees)
500 milliseconds
less than 200 µK
NAVG Noise (°C)
1 0.000673
2 0.000408
4 0.000191
8 0.000133
16 0.000081
32 0.000052
Note:
NAVG = number of A/D cycles per sample.
Interval between samples (seconds)
= (0.133 * NAVG) + 0.339
RS-232 (standard):
8 – 15 VDC at 10 milliamps average
RS-485 half-duplex (optional):
8 – 15 VDC at 6 milliamps average
Titanium pressure case rated at
10,500 meters (34,400 feet)
Weight
Notes:
1
NIST-traceable calibration applying over the entire range.
2
Time to reach 63% of final value following a step change in temperature.
In water: 0.5 kg (1.2 lbs)
In air: 0.9 kg (2.0 lbs)
7
Section 2: Description of SBE 38
Dimensions and End Cap Connector
The SBE 38 is available with a 4-pin XSG or optional MCBH (wet-pluggable)
external connector.
Pin Signal
1 Common
2 RS-232 Receive or RS-485 A
3 RS-232 Transmit or RS-485 B
4 Power
Baud Rate and Cable Length
Note:
Baud rate is set with the BAUD=
command. See Command
Descriptions in Section 4:
Deploying and Operating RS-232
SBE 38 for command details.
For RS-232, the length of cable that the SBE 38 can drive for transmitting
real-time data is dependent on the baud rate. The allowable combinations are:
Maximum Cable Length (meters) Maximum Baud Rate
800 1200
400 2400
200 4800
100 9600
8
Section 3: Preparing SBE 38 for Deployment
Section 3: Preparing SBE 38 for Deployment
This section describes the software installation and the pre-check procedure
for preparing the SBE 38 for deployment.
Installing Software
If not already installed, install SEATERM and other Sea-Bird software
programs on your computer using the supplied software CD:
1. Insert the CD in your CD drive.
2. Double click on Seasoft-Win32.exe.
Note:
It is possible to use the SBE 38
without SEATERM by sending
direct commands from a dumb
terminal or terminal emulator,
such as Windows HyperTerminal.
3. Follow the dialog box directions to install the software.
The default location for the software is c:/Program Files/Sea-Bird. Within that
folder is a sub-directory for each program.
Power and Communications Test
Locking
sleeve
Dummy plug or cable
Test Setup
1. If applicable, remove locking sleeve and dummy plug from bulkhead
2. Install the Sea-Bird I/O cable on the SBE 38:
3. Connect the I/O cable connector to your computer’s serial port.
4. Connect the I/O cable battery terminal clip to a 9-volt battery. Note that
connector:
A. By hand, unscrew the locking sleeve from the SBE 38’s bulkhead
connector. If you must use a wrench or pliers, be careful not to
loosen the bulkhead connector instead of the locking sleeve.
B. Remove the dummy plug from the SBE 38’s bulkhead connector by
pulling the plug firmly away from the connector.
• XSG Connector (shown in photos) - Align the raised bump on the
side of the connector with the large pin (pin 1 - ground) on the
SBE 38.
• MCBH Connector (optional) – Align the pins.
A 25-to-9 pin adapter is supplied for use if your computer has a 9-pin
serial port.
the 9-volt battery supplied with the SBE 38 will provide approximately
50 hours of operation.
9
Loading...