Vigilantplant TDLS8000, User Manual

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<9. Inspection and Maintenance>
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IM 11Y01D01-01EN
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Restoring calibration data
For zero and span calibration, you can restore past calibration results. You can restore separately
for zero and span. You can select the original data for restoring from the following two types.
• Previous
The calibration data executed previously is restored. When executed, the current calibration
data is saved as past data. Therefore, restoring twice will cause the current calibration data
to return.
• Factory
The factory default calibration data is restored. When executed, the current calibration data
is saved as past data. Therefore, if you restore using “Factory” and then using “Previous,”
the original current data will return.
Execution menu path:
[HART] “Diagnosis/Service>>Calibration>>Restore”
[YH8000] “ >>Execution>>Calibration>>Restore”
9.8 Automatic and Semi-automatic Execution
of Validation and Calibration
There are several methods to perform calibration and validation. One method is manual
calibration and validation, which you execute from the screen. Another method is automatic
calibration and validation, which are executed at a preset time or at preset time intervals. Yet
another method is semi-automatic calibration and validation, which are executed in response to a
start instruction from the YH8000, HART, digital input, or Modbus.
Since valves are controlled automatically in automatic and semi-automatic execution, you
need to set time for preparatory check gas or calibration gas purging. As shown in the following
figure, the time period during which calibration gas (or check gas) purging takes place is called
calibration (validation) time . The subsequent time period during which process gas purging
takes place is called stabilization wait time . The stabilization wait time is the wait time until the
measurements stably return to normal process values. The TDLS8000 is in a Cal/Val state until
the stabilization wait time is completed and holds the AO output. The following figure shows a
remote execution example. Digital input is used to start calibration (validation).
Digital input
Calibration (check)
gas purge
Process purge
AO, DO
Calibration
(Validation) time
Stabilization wait time
AO hold, DO on
NOTE
It is possible to disable the AO hold operation and DO ON operation that take place while
calibration or validation is being executed. For details, see “6.4.2 Output Hold” and “6.5.1 DO
Contact (DO-1)”.
3rd Edition: Jun. 10, 2016-00