Stratos Multi E461N
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7.4.5 Calibration Mode: Product
Calibration by Sampling
If the sensor cannot be removed – e.g., for sterility reasons – its cell constant can be determined by
“sampling”. The currently measured value (conductivity or concentration
1)
) of the process from
Stratos Multi is stored for this purpose. Right after this, take a sample from the process. The value of
this sample is measured under process conditions (same temperature!) wherever possible. The calcu-
lated value is entered in the measuring system. Stratos Multi calculates the conductivity sensor’s cell
constant from the deviation between the process measured value and the sample value.
Note:
Product calibration can also be carried out using PROFINET acyclic services.
Product Calibration without TC Compensation (With Conductivity)
A sample is taken from the process. The sample’s measured value is determined in the laboratory at
the temperature at which the sample was taken (“Sample Temperature”, see display). It may be neces-
sary to thermostat the sample in the laboratory accordingly. Temperature compensation of the refer-
ence measuring devices must be disabled (TC = 0 %/K).
Product Calibration with TC Compensation T
ref
= 25 °C/77 °F (With Conductivity)
A sample is taken from the process. During measurement in the laboratory (TC linear), the same values
for reference temperature and temperature coefficient must be set in both the reference measuring
device and Stratos Multi. In addition, the measuring temperature should match the sample tempera-
ture (see display) as closely as possible. The sample should be transported in a vacuum flask (Dewar)
to ensure this.
NOTICE!
Product calibration is only possible if the process medium is stable (no chemical reactions
that affect conductivity). At higher temperatures, evaporation may falsify results.
Calibration Procedure
Calibration
[I] [II] … Cond
When you access calibration, the calibration values selected in the calibration presettings are used.
These settings can still be changed in the Calibration menu. If you do not want to perform calibration,
use the left
softkey
to go back one level and abort the calibration.
01.
Select “Product”
Calibration Mode
and press
enter
to confirm.
02.
Prepare for sampling.
03.
Start with the
right softkey: Next
.
Product calibration is performed in 2 steps.
Calibration
Step 1: Sampling [Save]
Enter Lab Value [Entry]
Temperature
Conductivity
1.249 mS/cm
23.3 °C
Entry
Save
II
Step 1:
04.
Take sample.
✓
The measured value and temperature at the time of sampling are displayed.
1)
First enable TAN option FW-E009.
