User`s manual
Table Of Contents
- SEASAVE
- Limited Liability Statement
- Table of Contents
- Section 1: Introduction
- Section 2: Installation & Use
- Section 3: Configure Inputs, Part I - Instrument Configuration (.con file)
- Introduction
- Instrument Configuration
- Viewing, Modifying, or Creating .con File
- SBE 9plus Configuration
- SBE 16 SEACAT C-T Recorder Configuration
- SBE 16plus SEACAT C-T Recorder Configuration
- SBE 19 SEACAT Profiler Configuration
- SBE 19plus SEACAT Profiler Configuration
- SBE 21 Thermosalinograph Configuration
- SBE 25 SEALOGGER Configuration
- SBE 45 MicroTSG Configuration
- SBE 49 FastCAT Configuration
- Section 4: Configure Inputs, Part II - Calibration Coefficients
- Accessing Calibration Coefficients Dialog Boxes
- Calibration Coefficients for Frequency Sensors
- Calibration Coefficients for A/D Count Sensors
- Calibration Coefficients for Voltage Sensors
- Pressure (Strain Gauge) Calibration Coefficients
- Altimeter Calibration Coefficients
- Fluorometer Calibration Coefficients
- Methane Sensor Calibration Coefficients
- OBS/Nephelometer Calibration Coefficients
- Oxidation Reduction Potential (ORP) Calibration Coefficients
- Oxygen Calibration Coefficients
- PAR/Irradiance Calibration Coefficients
- pH Calibration Coefficients
- Pressure/FGP (voltage output) Calibration Coefficients
- Suspended Sediment Calibration Coefficients
- Transmissometer Calibration Coefficients
- User Polynomial (for user-defined sensor) Calibration Coefficients
- Zaps Calibration Coefficients
- Section 5: Configure Inputs, Part III – Serial Ports, Water Sampler, TCP/IP Ports, Miscellaneous, & Pump Control
- Section 6: Configure Outputs
- Section 7: Display - Setting Up SEASAVE Displays
- Section 8: Real-Time Data & Real-Time Control - Real-Time Data Acquisition
- Section 9: Archived Data Displaying Archived Data
- Section 10: Processing Data
- Appendix I: Command Line Operation
- Appendix II: Configure (.con) File Format
- Appendix III: Software Problems
- Appendix IV: Derived Parameter Formulas
- Index

Section 4: Configure Inputs, Part II - Calibration Coefficients
35
Calibration Coefficients for Frequency Sensors
For all calibration dialog boxes, enter the sensor serial number and calibration
date. Many sensor calibration equations contain an offset term. Unless noted
otherwise, use the offset (default = 0.0) to make small corrections for sensor
drift between calibrations.
Calibration coefficients are discussed below for each type of sensor.
Temperature, conductivity, and Digiquartz pressure sensors are covered first,
followed by the remaining frequency sensor types in alphabetical order.
Temperature Calibration Coefficients
Enter g, h, i, j (or a, b, c, d), and f0 from the calibration sheet.
Enter values for slope (default = 1.0) and offset (default = 0.0) to make small
corrections for temperature sensor drift between calibrations:
Corrected temperature = (slope * computed temperature) + offset
where
slope = true temperature span / instrument temperature span
offset = (true temperature – instrument reading) * slope; measured at 0 °C
Temperature Slope and Offset Correction Example
At true temperature = 0.0 °C, instrument reading = 0.0015 °C
At true temperature = 25.0 °C, instrument reading = 25.0005 °C
Calculating the slope and offset:
Slope = (25.0 – 0.0) / (25.0005 – 0.0015) = + 1.000040002
Offset = (0.0 – 0.0015) * 1.000040002 = - 0.001500060
Sea-Bird temperature sensors usually drift by changing offset, typically
resulting in higher temperature readings over time for sensors with serial
number less than 1050 and lower temperature readings over time for sensors
with serial number greater than 1050. Sea-Bird’s data indicates that the drift is
smooth and uniform with time, allowing users to make very accurate
corrections based only on pre- and post-cruise laboratory calibrations.
Calibration checks at sea are advisable to ensure against sensor malfunction;
however, data from reversing thermometers is rarely accurate enough to make
calibration corrections that are better than those possible from shore-based
laboratory calibrations.
Sea-Bird temperature sensors rarely exhibit span errors larger than ± 0.005 °C
over the range –5 to +35 °C (0.005 °C/(35 -[-5])C/year = 0.000125 °C/C/year),
even after years of drift. A span error that increases more than
± 0.0002 °C/C/year may be a symptom of sensor malfunction.
Notes:
• Coefficients g, h, i, j, and f0
provide ITS-90 (T
90
)
temperature; a, b, c, d, and f0
provide IPTS-68 (T
68
)
temperature. The relationship
between them is:
T
68
= 1.00024 T
90
• See Application Note 31 for
computation of slope and offset
correction coefficients from pre-
and post-cruise calibrations
supplied by Sea-Bird.
•
See Calibration Coefficients for
A/D Count Sensors below for
information on temperature
sensors used on the
SBE 16plus, 19plus, and 49.