Stratos Multi E401N
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6.4.5 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 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 calculated 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.
Product Calibration without TC Compensation
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
necessary to thermostat the sample in the laboratory accordingly. Temperature compensation of the
reference measuring devices must be disabled (TC = 0 %/K).
Product Calibration with TC Compensation T
ref
= 25 °C/77 °F
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.
Step 1:
04.
Take sample.
✓
The measured value and temperature at the time of sampling are displayed.
05.
Save with the
right softkey: Save
.
Exception: Sample value can be determined and entered on site:
Left softkey: Input
Step 2: Lab value has been measured.
06.
Open the Product Calibration menu again.
07.
Enter reference value ("Lab value").
08.
Confirm with the
right softkey: Next
or repeat calibration with the
left softkey: Abort
.
Result
✔
By pressing the
right softkey: Adjust
, the calibration values obtained during calibration for
calculation of the process variables are applied to the device. When using a Memosens sensors,
the calibration values are saved in the sensor.