Yokogawa 2-Wire Dual Channel Transmitter/Analyzer FLXA21 - Manual (Page 95)

<7. COMMISSIONING OF SC (Conductivity)>
7-3
IM 12A01A02-01E 5th Edition : Oct. 31, 2013-00
7.1 Measurement setup
This section describes how to set up various parameters relating to measurements.
Measurements are performed based on the measurement parameter setup.
7.1.1 Measurement
Select a measurement parameter from Conductivity, Resistivity, Concentration, and Conduct.
+ Concentr. The setting of the measurement parameter changes the menu structure in Error
configuration, Display setup, etc. accordingly.
7.1.2 Configure sensor
This section describes how to configure the sensor to be connected.
l Sensor type
Choose the sensor type from “2-electrode” and “4-electrode.”
Two-electrode sensors are usually used for conductivity and/or resistivity measurements.
However, polarization of the electrodes may occur at high conductivity ranges, which may cause
an error in conductivity measurement. To avoid this, use 4-electrode sensors.
l Measuring unit
Either /cm or /m can be chosen here.
The process values will be expressed in S/cm or S/m in conductivity mode or Ω.cm or Ω.m in
resistivity mode, respectively.
l Cell constant (factory)
The cell constant given at factory shipment is set.
When a new sensor is connected, set the new cell constant which is indicated on the sensor.
When a cell constant is changed, a calibrated cell constant (c.c. (adjusted)) will be the same
value of the new cell constant (factory) after resetting an old one.
The cell constant is indicated on the sensor nameplate, etc. by either of the following two ways:
• Cell constant indication and input methods
(1) When the cell constant itself is written on the sensor nameplate, enter it directly. (for
electrodes SC211G, SC8SG, and SC4AJ)
(2) When the “percentage of a deviation from the nominal cell constant (±□.□%)” is indicated on
the sensor nameplate, enter the cell constant as follows. (for electrode SC210G)
In case of the indication of a nominal cell constant of 5 cm -1 and a deviation value of
(CORR.%=-1.1):
The input cell constant is 5 x (100 – 1.1) / 100 = 4.945; enter this 4.945.
7.1.3 Temperature settings
Select the temperature element used for compensation from among Pt1000, Pt100, Ni100, 8k55,
and Pb36 (JIS 6k). Select the same type as the temperature element that is actually connected.
If a thermistor is used for the temperature sensor, select Pb36 (JIS 6k).
Celsius (°C) or Fahrenheit (°F) temperature units are available. If the unit is changed, the
following values are also recalculated automatically to the new unit:
• Manual temp.
• Reference temp.
• Temp. coefficient
• Temp. ranges in the matrix
SC
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