Entering Field Calibration Parameters; Direct Bias Adjustment; Configuring Prism Wash - Vaisala K-PATENTS PR-23 Series Instruction Manual

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PR-23 instruction manual
Press the ...wait while ...and press for next
FIELD REPEAT
soft key... DTR measures... data point or BACK to get to
SAMPLE
(take sample for lab) the Sensor status display.
Figure 6.13 Using FIELD SAMPLE soft key
– low flow which makes sample to form an unrepresentative film on the prism
– sample evaporation at high temperature or undissolved solids at low temperature
giving deviations from laboratory determinations
– an ageing sample which is not representative
– outside light reaching the prism
Thus calibration using the process liquid should always be made inline.

6.4.4 Entering field calibration parameters

The field calibration parameters supplied by Vaisala are entered by selecting
5 CALI-
from the Main menu, followed by first and
BRATION 1 CHEMICAL & FIELD PARAMETERS
then by .
2 FIELD CALIBRATION PARAMETERS
Important: If there is already a previous field calibration, it should be cleared (by
setting all values to 0) before entering a new field calibration.

6.4.5 Direct BIAS adjustment

The concentration measurement value can also be directly adjusted by changing the
field adjustment parameter f00.
The value of the bias parameter f00 will be added to the concentration value:
= + .
NEW CONC OLD CONC f00

6.5 Configuring prism wash

In some applications the process flow does not keep the prism clean because of sticky
process medium or low flow velocity. In these applications the prism can be automat-
ically cleaned by installing a wash system (see Chapter 4).
The prism wash settings for sensors A and B are independent of each other. The wash
system is active if a relay has been configured to be a wash relay (see Section 6.3.1)
and the wash time is not zero. An automatic wash function can be configured so that
both sensors have different parameters.