Servomex 07931001B, Руководство оператора

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© Servomex Group Limited. 2020 07931001B revision 6
Parameter Name Units Guidance
Low Signal Threshold ADC counts This should be set at a level that ensures that validation is
performed in low signal mode. LSM is best suited to
validation due to the extremely short path length. 250000
should be used for all applications apart from CO and
CO+CH4 which should use 500000
Final zero threshold % This is the threshold for testing the validation cell
concentration after the final purge. It should be set low
enough that it gives confidence that the cell has been
correctly purged. Care needs to be taken that it is not set so
low that the test fails because of process drift that has
occurred during validation.
Once the access code has been entered, auto validation can be started. Simply
write a 1 to the appropriate address to start auto validation.
The register is
•
Start or stop auto validation
Refer to the Modbus map in section 12.1.14 for the register address.
Things to note:
1. Auto Validation will not start if the analyzer is currently warming or in fault.
The HMI can monitor these on Modbus.
2.
Out of spec (“E”) faults are suppressed during auto validation. This is the
same as manual validation and is designed to stop spurious faults from
being reported. These can temporarily occur during validation as
measurement parameters are changed. As the system response changes
and settles to the new parameters, things can go out of spec for a few
seconds. Once auto validation has finished and the measurement has been
restored to normal, any remaining E faults are logged and reported in the
usual way.
It is possible to stop a running instance of auto validation. Write 0 to the same
register that was used to start auto validation.
Auto Validation will not stop instantly as the system has to be restored to normal
operation. This may involve purging the validation cell with zero-gas if it currently
contains span-gas.
The Laser 3 Plus will know where abouts it is in the auto validation sequence and
will automatically perform all necessary steps to correctly return the system to
normal operation.