Yokogawa EXA SC202 2-Wire Conductivity Transmitter/Analyzer - Manual (Page 58)

IM 12D08B02-01E
5-12 Parameter setting
5-4. Temperature compensation functions
Code 20 *T.R.°C Choose a temperature to which the measured conductivity (or resistivity) value
must be compensated. Normally 25°C is used, therefore this temperature is
chosen as default value. Limitations for this setting are: 0 to 100 °C.
If *T.UNIT in code 11 is set to °F, default value is 77°F and the limitations are
32 - 212°F.
Code 21 *T.C.1, 2 In addition to the procedure described in section 5-2-4 it is possible to adjust
the compensation factor directly. If the compensation factor of the sample liquid
is known from laboratory experiments or has been previously determined, it
can be introduced here.
Adjust the value between 0.00 to 3.50 % per °C. In combination with reference
temperature setting in code 20 a linear compensation function is obtained,
suitable for all kinds of chemical solutions.
Code 22 *MATRX The EXA is equipped with a matrix type algorithm for accurate temperature
compensation in various applications. Select the range as close as possible
to the actual temperature/concentration range. The EXA will compensate by
interpolation and extrapolation. Consequently, there is no need for a 100%
coverage.
If 9 is selected the temperature compensation range for the adjustable matrix
must be configured in code 23. Next the specific conductivity values at the
different temperatures must be entered in codes 24 to 28.
Code 23 *T1, T2, T3, Set the matrix compensation range. It is not necessary to enter equal
T4 & T5 °C temperature steps, but the values should increase from T1 to T5, otherwise
the entrance will be refused. Example: 0, 10, 30, 60 and 100 °C are valid
values for the T1....T5. The minimum span for the range (T1 - T5) is 25 °C.
Code 24-28 *L1xT1 - In these access codes the specific conductivity values can be entered for
L5xT5 5 different concentrations of the process liquid; each one in one specific access
code (24 to 28). The table below shows a matrix entering example for 1 - 15%
NaOH solution for a temperature range from 0 - 100 °C.
NOTES :
1. In chapter 11 a table is included to record your programmed values. It will make programming easy
for duplicate systems or in case of data loss.
2. Each matrix column has to increase in conductivity value.
3. Error code E4 occurs when two standard solutions have identical conductivity values at the same
temperature within the temperature range.
Table 5-2. Example of user adjustable matrix
Matrix Example Example Example Example Example
Code 23 Temperature T1...T5 0 °C 25 °C 50 °C 75 °C 100 °C
Code 24 Solution 1 (1%) L1 31 mS/cm 53 mS/cm 76 mS/cm 98 mS/cm 119 mS/cm
Code 25 Solution 2 (3%) L2 86 mS/cm 145 mS/cm 207 mS/cm 264 mS/cm 318 mS/cm
Code 26 Solution 3 (6%) L3 146 mS/cm 256 mS/cm 368 mS/cm 473 mS/cm 575 mS/cm
Code 27 Solution 4 (10%) L4 195 mS/cm 359 mS/cm 528 mS/cm 692 mS/cm 847 mS/cm
Code 28 Solution 5 (15%) L5 215 mS/cm 412 mS/cm 647 mS/cm 897 mS/cm 1134 mS/cm