Manual revision 005
Appendix I: Functional Description
SBE 63
39
The pressure correction equation is:
Pcorr = exp (E * P / K)
where
•
Pressure correction coefficient is constant -
E = 0.011
•
K = temperature in Kelvin = T + 273.15
where
T is temperature output from SBE 63’s thermistor in
°
C
•
P = pressure (dbar) from CTD data
o
For oxygen in ml/l output directly from the SBE 63,
SetRefP=
is
used as the pressure value in the pressure correction equation.
o
When the SBE 63 is integrated with a CTD (SeaCAT, MicroCAT, or
Argo CTD),
pressure calculated from the CTD data
should be used
to calculate converted oxygen (ml/L, mg/L, etc.).
- SeaCAT CTDs output raw phase delay and temperature from an
integrated SBE 63. Sea-Bird software automatically uses the pressure
from the CTD data if calculating converted oxygen output in Seasave
real-time data acquisition software or SBE Data Processing post-
processing software.
- MicroCAT CTDs can output raw phase delay and temperature
or
converted oxygen in ml/L from an integrated SBE 63, depending on
the user-selected output format in the MicroCAT. For converted
oxygen in ml/L, the MicroCAT firmware automatically uses the
pressure from the CTD data. Sea-Bird software automatically uses the
pressure from the CTD data if calculating converted oxygen output in
SBE Data Processing post-processing software.
Sea-Bird provides two calibration sheets with each SBE 63 –
•
One relates the SBE 63 oxygen sensor output to oxygen concentration in
ml/L – with coefficients a
0
,
a
1
,
a
2
,
b
0
,
b
1
,
c
0
,
c
1
,
c
2
, and E.
•
One relates the SBE 63 thermistor output to temperature (
°
C) –
with coefficients t
a0
, t
a1
, t
a2
, t
a3
Examples of both calibration sheets are shown on the next two pages.
