Servomex 07931001B, Руководство оператора

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07931001B revision 6 © Servomex Group Limited. 2020
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Parameter Name Units Guidance
Validation pressure Pressure units currently in
use in the Laser 3 Plus Set this to the pressure in the in-line validation cell. This is
usually atmospheric pressure: 101325 Pa.
Validation
temperature Temperature units
currently in use in the
Laser 3 Plus Set this to the temperature of the validation gas.
This is usually room temperature at 296 K
Validation gas
concentration % or ppm Set this to the concentration of the validation gas bottle.
Validation gas
tolerance This parameter is currently not used and should be set to
zero
Validation pass level Percent Difference %, This
is the absolute value of the
difference in % between
the validation result and
the validation bottle you
are prepared to accept for
your application. Refer to section 6.13.8.15 for details of how the test result is
calculated and therefore how the pass level should be set.
Validation cell length Length units currently in
use in the Laser 3 Plus Set this to the length of the validation cell
Validation
concentration
standard deviation
tolerance % The concentration standard deviation is a standard deviation
value expressed as a percentage of the target measurement.
Concentration standard deviation tolerance is used as the
lower threshold when calculating whether the measurement
is stable. Refer to section 6.13.8.5 for an explanation of how
measurement stability is calculated.
When setting this parameter, it should be set as low as
possible to ensure an accurate validation measurement.
Validation
transmission
standard deviation
tolerance Counts The transmission standard deviation is a raw value in counts
that is the standard deviation of the current transmission
ADC count. The transmission standard deviation tolerance is
the lower threshold to be used when calculating whether the
measurement is stable.
When setting this parameter, it should be set as low as
possible to ensure an accurate validation measurement.
Stability Time Seconds This is the continuous length of time that the process or the
validation measurement must meet the stability criteria for
to pass the stability test.
Around 60 seconds is usually a good value.
Timeout Seconds
If the measurement hasn’t passed the stability test by
the
time this timeout has elapsed, then the stability test will be
abandoned and auto validation will automatically advance to
the next stage.
Around 300 seconds is usually a good value.
Flush time Seconds Once the Laser 3 Plus has asked for either the zero-gas or
span-gas to be turned on it will wait for this length of time for
the gas to fully purge through the valves, pipework and
validation cell.
The correct value for the flush time is dependent on the
physical configuration of the application and the level of
surface adhesion of gas molecules, for example, NH3 and CO
require higher flush times than O2 and N2
.