User`s manual

Section 4: Configure Inputs, Part II - Calibration Coefficients
39
Calibration Coefficients for Voltage 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. Strain
gauge pressure sensors are covered first, followed by the remaining voltage
sensor types in alphabetical order.
Pressure (Strain Gauge) Calibration Coefficients
Enter coefficients:
• Pressure sensor without temperature compensation
¾ Enter A0, A1, and A2 coefficients from the calibration sheet
¾ For older units with a linear fit pressure calibration, enter M (A1) and
B (A0) from the calibration sheet, and set A2 to zero.
¾ For all units, offset is normally zero, but may be changed for non-
zero sea-surface condition. For example, if the in-air pressure reading
is negative, enter an equal positive value.
• Pressure sensor with temperature compensation
Enter ptempA0, ptempA1, ptempA2, pTCA0, pTCA1, pTCA2, pTCB0,
pTCB1, pTCB2, pA0, pA1, and pA2 from the calibration sheet.
Altimeter Calibration Coefficients
Enter the scale factor and offset.
altimeter height = [300 * voltage / scale factor] + offset
where
scale factor = full scale voltage * 300/full scale range
full scale range is dependent on the sensor (e.g., 50m, 100m, etc.)
full scale voltage is from calibration sheet (typically 5V)
Fluorometer Calibration Coefficients
• Biospherical Natural Fluorometer
Enter Cfn (natural fluorescence calibration coefficient), A1, A2, and B
from calibration sheet.
natural fluorescence Fn = Cfn * 10
V
production = A1 * Fn / (A2 + PAR)
chlorophyll concentration Chl = Fn / (B * PAR)
where
V is voltage from natural fluorescence sensor
Note:
To enter the altimeter alarm set point,
alarm hysteresis, and minimum
pressure to enable alarm, click the
SBE 11plus Alarms and/or SBE 14
Remote Display tabs, as applicable,
in SEASAVE’s Configure Outputs.
Note:
See Calibration Coefficients for A/D
Count Sensors above for information
on strain gauge pressure sensors
used on the SBE 16plus, 19plus,
and 49. See Calibration Coefficients
for Frequency Sensors above for
information on Paroscientific
Digiquartz pressure sensors.
Note:
Unless noted otherwise, SEASAVE
supports only one of each auxiliary
sensor model on a CTD (for example,
you cannot specify two Chelsea
Minitracka fluorometers, but you can
specify a Chelsea Minitracka and a
Chelsea UV Aquatracka fluorometer.
See the sensor descriptions in below
for those sensors that SEASAVE
supports in a redundant configuration
(two or more of the same model
interfacing with the CTD).