Hanna Instruments HI 4521 - Manual (Page 24)

24
Delete Profile
To delete one of the existing profiles:
• Use or to select the Profile option.
• Press and use or to highlight the
Delete Profile option.
• Press . A list with all customised profiles will appear on
the screen.
• Use or to select the desired profile and press
.
• Press to return to the previous menu.
Note: The saved profile will automatically become the current profile.
Load Profile
To load one profile:
• Use or to select the Profile option.
• Press and use or to highlight the
Load Profile option.
• Press . A list with all customised profiles will be displayed
on the screen.
• Use or to select the desired profile and press
to confirm or to exit without selecting.
93
PRACTICAL SALINITY SCALE (UNESCO 1978) PRACTICAL SALINITY SCALE (UNESCO 1978) PRACTICAL SALINITY SCALE (UNESCO 1978) PRACTICAL SALINITY SCALE (UNESCO 1978) PRACTICAL SALINITY SCALE (UNESCO 1978)
According to the definition, salinity of a sample in psu (practical salinity units) is calculated using the
following formula:
where:
R
T
- coefficient;
C
T
(sample) - uncompensated conductivity at T °C;
C(35,15)= 42914 µ S/cm - the corresponding conductivity of KCl solution containing a mass of 32.4356 g
KCl / 1 Kg solution;
r
T
- temperature compensation polynom
a
0
=0.008 b
0
=0.0005
a
1
=-0.1692 b
1
=-0.0056
a
2
=25.3851 b
2
=-0.0066
a
3
=14.0941 b
3
=-0.0375
a
4
=-7.0261 b
4
=0.0636
a
5
=2.7081 b
5
=-0.0144
c
0
=0.008
c
1
=0.0005
X=400R
T
Y=100R
T
f(T)=(T-15)/[1+0.0162(T-15)]
Note: The formula can be applied for salinity values between 0 and 42 psu.
The formula can be applied for temperatures between -2 °C and 35 °C.