RBR 1050 Series, User Manual

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Depth The calculation of depth requires a pressure input from the logger and
may be based on a simplified calculation (where the density of water defaults to
1.0) or a seawater calculation based on the UNESCO Technical Paper in Marine
Science #44. This latter calculation uses the latitude of the data collection.
Atmospheric pressure is a required input to correct the pressure measurements
during the depth calculation; this defaults to 10.132500 deciBar. The logger
software assumes a gravitational constant of 0.980665 m/s
2
for the simplified
case.
Conductivity Correction can be applied to a conductivity measurement using the
following formula:
( )
( )
cP
T T
b
a
C
C
c
m
cor
+ − +
=
1
Where:
C
cor
is the Corrected Conductivity;
C
m
is the Measured Conductivity;
T is the Temperature;
P is the Hydrostatic Pressure;
and
a, b, c & T
c
are experimentally determined constants.
The parameters
a, b, c & T
c
are stored for the version of the RBR
Windows Software and the one set is applied to all conductivity
measurements from all loggers.
Density Anomaly is calculated based on the UNESCO Technical Paper in Marine
Science #44.
Salinity is calculated according to the Practical Salinity Scale.
Specific Conductivity is calculated from Standard Methods for the Examination of
Water and Wastewater (1989) Ch. 2, L. S. Clesceri et al Eds., American Public
Health Association, Washington D.C., 17th Ed.
Speed of Sound can be calculated by one of three formulas: UNESCO,
del Grosso or Wilson.
Dissolved Oxygen
There are two areas for the definition of derived units:
1 Oxyguard Sensor This sensor provides a measure of the oxygen saturation
(%) and a value of the oxygen concentration is derived the saturation using the
Weiss equation and can be output in one of three standard ways (µMol/l, mg/l
and ml/l). The calculation requires a temperature and salinity. The boxes on the
right of the window allow for standard values to be inserted when the particular
logger does not have the appropriate sensor.
2. Aanderaa Optode This sensor can be configured to provide oxygen saturation
(%) or concentration (µMol/l). When configured in the concentration mode,
derived units of concentration in mg/l or ml/l can be calculated as well as the
saturation which uses the Garcia and Gordon equation.