Galvanic Applied Sciences ProTech903, Руководство по эксплуатации

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Revision 14
104 August 02, 2019
•
Time Check Box - When the
Time
check box is checked, the operator can perform a run
as defined by the
Frequency
section of the gas run type tab below.
If the Time check box is not checked , the gas run will not start without being configured in
the Sequence or Timers Tabs or a via a manual initiation by clicking on the gas run type
button such as the
Stream 1 H2S
button.
•
Stream 1 H2S
– Initiates a run using the indicated parameters.
• Sample Delay and Sample Interval – The sample delay time and sample interval time
added together make the total analysis cycle time. The sample delay and sample interval
are used differently depending on which analysis algorithm is in use; the standard (peak
detect) algorithm of the fixed time analysis algorithm.
• Standard Analysis (Peak Detect) When the standard analysis (peak detect) algorithm is
used, the software detects the point during the analysis where the rate of change in the
detector signal reaches a maximum value. At this point the concentration of H2S is
calculated and stored until either the end of the cycle or a new maximum rate of change
value is detected. During the sample delay time the analyzer will not search for the
maximum rate of change as noise due to the tape advance may be present, which could
lead to a false maximum reading. The sample delay is set to a default value of 10 seconds.
During the sample interval, the analyzer will be allowed to search for the maximum rate of
change in the detector signal. The sample interval is set to 230 seconds by default. This
gives a default complete analysis cycle time of 240 seconds.
•
Fixed Time Analysis : When the fixed time analysis algorithm is used, the analyzer
calculates the average rate of change in the detector signal over a fixed period of time,
called the sample interval. The analyzer will not calculate the average rate of change in the
detector signal during the sample delay because the detector signal rate of change is
generally not stable during this time period. Typically the sample delay is around 120 to
180 seconds for the fixed time analysis and the sample interval is around 30 - 60 seconds.
This gives a total cycle time of 3 to 4 minutes.
The type of analysis algorithm used will depend on the analyzer’s specific application and is
set up at the factory. The type of algorithm used and the sample delay and interval values
should not be changed without consulting the Galvanic Applied Sciences.
•
Tape Saturation Cut-off (TSC) - The
tape saturation cut-off
is the sensor output at which
the analyzer will automatically cease the current analysis, calculate the concentration value
for the current analysis, update all outputs, advance the tape, recalibrate the sensor block,
and begin a new analysis cycle. This TSC level is set to 2500mV by default, and represents
a very dark stain on the tape. When the stain is very dark, the rate of change in the detector
signal becomes very small, and so it is very unlikely that a maximum rate of change in the
detector signal would be reached beyond this point. The TSC takes precedence over the
sample interval time for completion of an analysis – that is to say, if the sensor output
reaches the TSC prior to the completion of the sample interval time, the analysis will be
considered to be complete. Thus, the sum of the sample delay and sample interval times in
the standard analysis mode is only a maximum cycle time value. The actual cycle time
could potentially be shorter. To have a better chance of the maximum cycle time being the
actual cycle time, the TSC value should be set to a very high value in the GUI (a large value
is set at the factory). Setting the TSC value to a high level makes it much more likely that
the analysis time will reach the end of the sample interval prior to reaching the TSC.
•
Name Field – used to enter the name that will be displayed in the
Current Analysis
field in
the Analysis tab. It will also be displayed on the analyzer LCD screen when the run types
are displayed under the F1 STRM menu. The default name is the same as the gas run tab
name. For example, it will typically have the name ‘H2S’ if on the H2S tab or T.S. if on the
Total Sulfur tab.