Yokogawa 2-Wire Dual Channel Transmitter/Analyzer FLXA21 - Manual (Page 107)

<7. COMMISSIONING OF SC (Conductivity)>
7-15
IM 12A01A02-01E 5th Edition : Oct. 31, 2013-00
7.6.3 Auto Return
When no operation is performed for the time set in “Auto Return”, the display returns to the
Monitor display (or to the Main display when the MONITOR display is disabled) and the analyzer
returns to a normal measuring mode. (When the Trend display is selected, the Auto Return
doesn’t work.)
Select the time from among Disable, 10 min, and 60 min. When the Auto Return function is not
used, select “Disable.”
NOTE
A default is “10 min”. When maintenance like a calibration that may take much time is performed,
“60 min” or “Disable” is recommended to be selected.
7.6.4 Adjust contrast
The LCD screen contrast can be adjusted.
Pressing the ▲▼ keys adjusts the contrast in 11 levels from +5 to –5 (including the default value
of “0”).
7.6.5 MONITOR display
Select “Enable” so that the Monitor display becomes available. A default is “Enable”.
During Hold condition and a warning/fault condition, the Main display or the Home display is
displayed to indicate the condition.
7.7 Calculated data setup
On this setup, parameters can be set for calculated data.
When two modules are installed on the instrument, the calculated data can be set for conductivity
values or resistivity values measured by two sensors.
On the Calculated data setup screen, select one kind of calculations as shown on the Table 7.4.
For resistivity, select “Differential” or “Average”.
Table 7.4 Calculation
Function Arithmetic expression Indication *
Differential (value of the sensor 1) – (value of the sensor 2) Diff
Average (value of the sensor 1 + value of the sensor 2) / 2 Ave
Ratio (value of the sensor 1) / (value of the sensor 2) Ratio
Passage(%) (value of the sensor 2) / (value of the sensor 1) x 100 Pass
Rejection(%) (value of the sensor 1 – value of the sensor 2) / (value of the sensor 1) x 100 Reje
Deviation(%) (value of the sensor 2 – value of the sensor 1) / (value of the sensor 1) x 100 Dev
pH calc.(VGB) pH = 8.6 + log {(value of the sensor 1) – (value of the sensor 2) /3} VGB
* Parameter symbol at the bar display of analog output which is displayed at the bottom of the Main display or the Home display
when a calculated data is selected as a process parameter on the “mA (Output)” setup screen.
To display the calculated result, select “Calculated” on the Dual display screen. (Section 7.6.1.)
(The setting on the “Individual display” has no effect.)
While displaying a calculated data, measurement value of the sensor 1 or sensor 2 can be
checked on the each sensor’s display with pressing
Sensor
1
or
Sensor
2
at the lower right on the Main
display.
SC
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