YOKOGAWA SC402G, Руководство пользователя

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IM 12D08N04-01E
5-16
5. Parameter Setting
5-3-1. Parameter specific functions
Code 1 *SC/RES Choose the required parameter, either conductivity or resistivity. If the param-
eter is changed the instrument will go into reset to load parameter specific de-
fault values, followed by starting measurement. For all other service codes the
instrument will return to commissioning mode after the service code setting is
finished.
Code 2 *4.ELEC Choose the required sensor type. Normally conductivity and/or resistivity mea-
surements are done with 2-electrode type sensors. At high conductivity ranges,
polarisation of the electrodes may cause an error in conductivity measurement.
For this reason 4-electrode type sensors may be neccessary. Alternatively an
inductive conductivity measurement system may be used.
Code 3 *0.10xC Enter the factory calibrated cell constant mentioned on the text plate of the sen-
sor to be used. (There are two types of notations for the cell constant on the text
plate. Read “How to enter the cell constant.”) This avoids the need for calibra-
tion. Any value between 0.008 and 50.0 /cm may be entered. First select a
multiplying factor, and then set the constant in consideration of this factor. The
position of the decimal point can be selected after the first digit has been set
(when the decimal point is flashing).
*How to enter the cell constant
(1) In the case that the only cell constant is mentioned on the text plate of the sensor
(SC211G, SC8SG, SC4A).
How to enter the cell constant of 0.0195 /cm:
Select *0.01xC on the message display, and then enter the value of 1.950 on the main
display.
(2) In the case that the deviation of a nominal cell constant (
±
X.X%) is mentioned on the
text plate of the sensor (SC210G).
When the nominal cell constant is 5 /cm and the deviation (CORR.% = -1.1) is men-
tioned:
The cell constant to be entered is calculated as follows:
5 + 5 x (-1.1/100) = 4.945
How to enter the cell constant of 4.945 /cm:
Select *10.0xC on the message display, and then enter the value of 0.495 (rounded to
three decimal places) on the main display. (The first digit in the constant setting only
accepts 1 or 2.)
NOTE
If the actual cell constant is changed after a calibration or if the entered cell constant
differs from previous value, then the message “RESET?” will appear on the second line
display. After pressing “YES” the entered value becomes the new nominal and cali-
brated cell constant. After pressing “NO” the update proce dure of the cell constant entry
is canceled.
Code 4 *AIR To avoid cable influences on the measurement, a “zero” calibration with a dry
sensor may be done.
Code 5 *POL.CK The EXA SC402G has a polarisation check capable of monitoring the signal
from the cell for distortion of capacitive or polarisation errors. If there is a
problem with the installation or the cell becomes fouled, this will trigger E1.
For some application this error detecting can cause unwanted signals during
operation. Therefore this code offers the possibility to disable/enable this check.