Vaisala K-PATENTS PR-23 Series, Инструкция по эксплуатации

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54 PR-23 instruction manual
Press the
FIELD
SAMPLE
soft key...
...wait while
DTR measures...
(take sample for lab)
...and press
REPEAT
for next
data point or BACK to get to
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-
BRATION
from the Main menu, followed by first
1 CHEMICAL & FIELD PARAMETERS
and
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.