Note that if
NONE
is selected then the temperature used for compensation and displayed will be
that selected at the
dEF "C
function.
5.26
Default temperature value
Display:
dEF "C
Range:
0.0
to
200.0
Default Value:
25.0
Displays and sets the default temperature for manual compensation when
"CtyPE
is set to
NONE
.
If no temperature sensor is used set this function to the temperature required for temperature
compensation calculation i.e. set this to the known temperature of the process solution.
5.27
Solution temperature compensation slope
Display:
SOL SLPE
Range:
-6.00
to
0.00
Default Value:
-2.00
Displays and sets the solution slope, variable from -6.00 to 0.00. The solution slope gives the
temperature coefficient of the solution measured as a % per
o
C (this figure is needed since each
individual solutions conductivity/resistivity will vary differently with temperature) . A typical
value is -2% per
o
C for water. Enter the solution value, if known, if the solution slope is not known
then it can be obtained as follows:
1. Set the slope setting to
0.00
2. Place the cell into a sample of the process solution. Measure the temperature of the solution
or alter the temperature to a desired level, this temperature is shown as T1 in the formula
below. Allow the reading to stabilise and note the reading.
3. Bring the solution up to a higher temperature and allow the reading to stabilise, again note
the reading.
4. Use the formula below to calculate the solution slope.
Slope
=
Conductivity or Resistivity at T
1
Conductivity or Resistivity at T
2
−
1
!
(
1
T
2
−
T
1
)
×
100
5. Enter the result as the solution slope.
5.28
Solution temperature compensation reference
Display:
SOL "C
Range:
0.0
to
100.0
Default Value:
25.0
Displays and sets the solution temperature (T1) to be used with the solution slope function above
for automatic temperature compensation calculation. The default value is set at 25
o
C as this is
PM4COMAN-2.2-1
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