YOKOGAWA Exaxt450, Руководство пользователя

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IM 12D08N05-01E
4-3
<4. OPERATION>
4.3.4 C.C. (factory)
The nominal cell constant as determined by the factory calibration during production. This
value is set during commissioning, and is found on the nameplate of the sensor or the
calibration certificate.
Routing: Commissioning >> Measurement setup >> Configure sensor
4.3.5 C.C. (adjusted)
The calibrated cell constant. When the cell constant of the system is adjusted on-line by
grab sample or by calibrated solution technique, the new cell constant is recorded here.
This value should not deviate greatly from the original factory calibration. In the event that
there is a significant discrepancy seen between this reading and the C.C. (factory) value,
the sensor should be checked for damage and cleanliness.
Routing is via the “Calibration” menu.
4.3.6 Temp. comp 1
The chosen temperature compensation method for the primary measurement.
Routing: Commissioning >> Measurement setup >> Temp.compensation
4.3.7 Temp. comp 2
The chosen temperature compensation method for the secondary measurement.
Note: This does not imply two separate measurements. There is the possibility to set two separate
compensation methods so that two different stages of the same process can be monitored
accurately. An example is process/cleaning fluid interface.
Routing: Commissioning >> Measurement setup >> Temp.compensation
4.3.8 Polarization
The polarization is measured by the input circuitry. Monitoring this figure gives a guide to
progressive fouling of the sensor.
4.3.9 Sensor ohms
The input measurement as an uncompensated resistance value.
4.3.10 Last calibrated at
The date of the last calibration
4.3.11 Calibration due at
In the time frame scheduled for the next calibration. This field is determined by the
calibration interval.
Routing: Commissioning >> Measurement setup >> Calibration settings
4.3.12 Projected calibration at
A diagnostic output, showing the time frame when the unit should next be maintained
according to the sophisticated self-diagnostic tools built into the EXAxt software (for
example >12 months, 3-6 months or 0-1 month).