Sample Gas Flow Calculation; O 3 Supply Air Flow Sensor - Teledyne T200 User Manual

SAMPLE GAS FLOW CALCULATION

Sample gas flow in the analyzer is not a directly measured value, but is rather calculated
based on the measured pressure differential across the sample gas critical flow orifice.
Specifically, the upstream reading of the sample pressure sensor is compared to the
downstream pressure reading of the vacuum pressure sensor, and this differential is used
by the analyzer's CPU to derive the gas flow rate through the reaction cell.
• The results of this calculation are viewable in the Dashboard and/or in the Home page
meter if configured to display Sample Flow. (To configure, see Section 2.5.3 for
Dashboard, and Section 2.5.6 for Home page meter).
O SUPPLY AIR FLOW SENSOR
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In contrast to the sample gas flow, the ozone flow is measured with a mass flow sensor,
which is mounted on the flow/pressure sensor PCA just behind the PMT sensor assembly.
Pneumatically, it lies between the sample dryer and the O
has a full scale range of 0-1000 cc/min and can be calibrated through software to its span
point (Section 4.5).
Since the flow value displayed on the front panel is an actual measurement (and not a
calculated value), short term variability in the measurement may be higher than that of the
sample flow, which is based on a calculation from (more stable) differential pressures. On
the other hand, any sustained drift, i.e. long-term change, in the ozone flow rate may
usually indicate a flow problem.
This information is used to validate the O
If the flow rate exceeds ±15% of the nominal flow rate (80 cc/min), an O3 Flow
•
message appears in the Alerts page, and the O3 generator is turned off, triggering a
corresponding message in the Alerts page.
• The value for this flow measurement is viewable as O3 Flow.
As with all other test parameters, we recommend to monitor the ozone flow over time for
predictive diagnostics and maintenance evaluation.
194 Teledyne API T200 NO/NO
gas flow rate.
3
/NO Analyzer with NumaView™ Software
2 x
generator. This mass flow sensor
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083730200A DCN7962