Absence Of Analyzer Response To Sample Gas; Unstable Zero And Span - Teledyne T200 User Manual

ABSENCE OF ANALYZER RESPONSE TO SAMPLE GAS

If the instrument shows no response (display value is near zero) even though sample gas is
supplied properly and the instrument seems to perform
1. Carry out an electrical test with the ELECTRICAL TEST procedure (Run ETest)
in the Utilities>Diagnostics>OE Test menu. See Electrical Test (ETest) in Section
5.7.9.11.
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2. Carry out an optical test using the OPTIC TEST procedure (Run OTest) in the
Utilities>Diagnostics>OE Test menu. See Optic Test (OTest) in Section 5.7.9.11.
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3. Check if the ozone generator is turned on.
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4. Confirm the lack of response by supplying NO or NO
the range value to the analyzer.
5. Check the sample flow and ozone flow rates for proper values.
6. Check for disconnected cables to the sensor module.
7. If the NO
the NO

UNSTABLE ZERO AND SPAN

Leaks in the external gas supply and vacuum systems are the most common source of
unstable and non-repeatable concentration readings.
1. Check for leaks in the pneumatic systems as described in Section 5.6.11.
2. Consider pneumatic components in the gas delivery system outside the analyzer
such as a change in zero air source (ambient air leaking into zero air line or a worn-
out zero air scrubber) or a change in the span gas concentration due to zero air or
ambient air leaking into the span gas line.
146 Teledyne API T200 NO/NO
If this test produces a concentration reading, the analyzer's electronic signal
path is correct.
If this test results in a concentration signal, then the PMT sensor and the
electronic signal path are operating properly.
If the analyzer passes both ETest and OTest, it is capable of detecting light
and processing the signal to produce a reading.
Therefore, the problem must be in the pneumatics or the ozone generator.
Usually, the analyzer issues a warning whenever the ozone generator is
turned off.
Go to Utilities>Diagnostics>O3 Gen Override and see if it shows ON.
If it shows OFF, turn it ON and check the O3 Flow reading in the
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Dashboard menu.
If this is done and the ozone flow is correct, the analyzer should be
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properly supplied with ozone unless the generator itself is broken.
signal is zero while NO signal is correct, check the NO/NOx valve and
2
converter for proper operation.
2
/NO Analyzer with NumaView™ Software
2 x
correctly:
span gas of about 80% of
2
083730200A DCN7962