Yokogawa 2-Wire Dual Channel Transmitter/Analyzer FLXA21 - Manual (Page 155)

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IM 12A01A02-01E 5th Edition : Oct. 31, 2013-00
13.2.6 Calibration settings
In “Calibration settings,” set the high and low limits of Zero/Slope and set up parameters relating
to stabilization performed during calibration.
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Limits and timing
Zero High/Low
Set the high and low limits of Zero. During calibration, it is checked whether the new zero
exceeds these high and low limits. Narrowing the band will prevent bad calibration procedures
and calibration of bad sensors, which results in higher accuracy. The default values should be
adjusted to suit the application and the “users” criterion.
Slope High/Low
Set the high and low limits of Slope. During calibration, it is checked whether the new slope
exceeds these high and low limits. Narrowing the band will prevent bad calibration procedures
and calibration of bad sensors, which results in higher accuracy. The default values should be
adjusted to suit the application and the “users” criterion.
Stabilization time
During calibration, the stability of the measurement is constantly monitored. When variations of
the value are within a value set in Step Range over this stabilization time set here, the value is
regarded as being stable. If the value does not stabilize within 60 minutes, calibration is aborted.
Step Range
Set the range over which the stability of a measured value is checked. If variations of a measured
value over the stabilization time are within this set value, the measured value is judged to have
stabilized.
Calibr. interval
Set the interval in which a new calibration must take place. If the interval set here is exceeded,
the instrument will be notified according to the setting in “Calib. time exceeded” in the error
configuration.
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Zero/Slope
You can enter zero and slope values directly.
Zero current values can be set only when the setting of “Zero Calibration” is “Enabled.”
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Pressure comp. (Cal.)
You can enter the pressure level directly.
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Zero Calibration
If zero calibration is required, select “Enabled” for this parameter. The default value is “Disabled.”
When this feature is enabled, “Zero current values” can be set in zero settings.
NOTE
When the zero calibration is set to “disabled” after performing the calibration, the result of the
calibration turns invalid (default).