IM 12D08N05-01E
8-1
<8. TROUBLESHOOTING>
8. TROUBLESHOOTING
If you contact the local sales/ service organization the serial number and software revision
(section 4.3.14) is necessary information. Without that information it is impossible to help
you. It is also very useful to report all the information that you find on the zoom-in display.
The SC450G is a microprocessor-based converter that performs continuous self-
diagnostics to verify that it is working correctly. Error messages resulting from faults in the
micro-processor systems itself are monitored. Incorrect programming by the user will also
result in an error, explained in a message, so that the fault can be corrected according to
the limits set in the operating structure. The SC450G also checks the sensor system to
establish whether it is still functioning properly.
In the main display screen is a “Status Information” button that will show
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For information
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For warning
- a potential problem is diagnosed, and the system should be checked.
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For FAIL
, when the diagnostics have confirmed a problem, and the system must be checked.
This button gives access to a status report page, where
“The most applicable error”
will
be displayed. (
“No errors”
is displayed during proper operation)
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Explanation
>> Description or error message and possible remedies
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Advanced troubleshooting
>> Error code screen that is used in conjunction with the service manual. This data
may also be needed in the event that you request assistance from a Yokogawa service
department.
What follows is a brief outline of the SC450G troubleshooting procedures including
possible causes and remedies.
8.1 Calibration check
The SC450G converter incorporates a diagnostic check of the adjusted cell constant value
during calibration. If the adjusted value stays within 80-120 % of the factory value, it is
accepted, otherwise, the unit generates an error message, and the calibration is rejected.
8.2 Polarization check
The SC450G performs on-line monitoring to detect polarization. This is an early indicator
for sensor fouling. The detection of polarization in the measurement gives a warning of the
onset of sensor coating, before significant measuring errors build up.
