Non-Repeatable Zero And Span; Inability To Span - No Span Button (Cals); Inability To Zero - No Zero Button (Calz); Other Performance Problems - Teledyne T400 User Manual

5.7.6.2 NON-REPEATABLE ZERO AND SPAN

As stated earlier, leaks both in the T400 and in the external system are a common source
of unstable and non-repeatable readings.
• Check for leaks in the pneumatic systems as described in Section 5.6.3.
• A change in zero air source such as ambient air leaking into zero air line, or;
• A change in the span gas concentration due to zero air or ambient air leaking into the
• Once the instrument passes a leak check, perform a flow check (see Section 5.6.6)
• Confirm the sample pressure, sample temperature, and sample flow readings are
• Verify that the sample filter element is clean and does not need to be replaced.
5.7.6.3 INABILITY TO SPAN – NO SPAN BUTTON (CALS)
• Confirm that the O
• Check for leaks in the pneumatic systems as described in Section 5.6.3.
• Make sure that the expected span gas concentration entered into the instrument
• Check to make sure that there is no ambient air or zero air leaking into span gas line.
5.7.6.4 INABILITY TO ZERO – NO ZERO BUTTON (CALZ)
• Confirm that there is a good source of zero air. If the IZS option is installed, compare
• Check for leaks in the pneumatic systems as described in 5.6.3.
• Check to ensure that there is no ambient air leaking into zero air line.
5.7.7 O P
THER
Dynamic problems (i.e. problems which only manifest themselves when the analyzer is
monitoring sample gas) can be the most difficult and time consuming to isolate and
resolve. The following provides an itemized list of the most common dynamic problems
with recommended troubleshooting checks and corrective actions.
5.7.8 T
EMPERATURE
Individual control loops are used to maintain the set point of the UV Lamp, IZS Ozone
Generator (Optional) and Metal Wool Scrubber (Optional) temperatures. If any of these
temperatures are out of range or are poorly controlled, the T400 will perform poorly.
083730400A DCN8130
consider pneumatic components in the gas delivery system outside the analyzer
such as:
span gas line.
to make sure adequate sample is being delivered to the sensor assembly.
correct and have steady readings.
span gas source is accurate.
3
inter-comparing the source with another calibrated monitor, or having the O
verified by an independent traceable photometer.
during calibration is the correct span gas concentration and not too different from
expected span value.
the zero reading from the IZS zero air source to the calibration zero air source.
P
ERFORMANCE ROBLEMS
P
ROBLEMS
Teledyne API – Model T400 O
This can be done by
Analyzer
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Also
source
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