Teledyne 9110TH - Nitrogen Oxides Analyzer - Manual (Page 273)

Troubleshooting & Repair Model 9110TH NOx Analyzer
Teledyne Analytical Instruments 253
7.8. FREQUENTLY ASKED QUESTIONS
The following list contains some of the most commonly asked questions relating to the
Model 9110TH/M NO
x
Analyzer.
QUESTION ANSWER
Why does the instrument not
appear on the LAN or Internet?
Most problems related to Internet communications via the Ethernet card will
be due to problems external to the instrument (e.g. bad network wiring or
connections, failed routers, malfunctioning servers, etc.) However, there
are several symptoms that indicate the problem may be with the Ethernet
card itself. If neither of the Ethernet cable’s two status LED’s (located on the
back of the cable connector) is lit while the instrument is connected to a
network:
 Verify that the instrument is being connected to an active network jack.
 Check the internal cable connection between the Ethernet card and the
CPU board.
Why does the ENTR button
sometimes disappear on the front
panel display? Sometimes the ENTR button will disappear if you select a setting that is
invalid or out of the allowable range for that parameter, such as trying to set
the 24-hour clock to 25:00:00 or a reporting range outside the specified
limits. Once you adjust the setting to an allowable value, the ENTR button
will re-appear.
Why is the ZERO or SPAN button
not displayed during calibration? The 9110TH/M disables these buttons when the span or zero value entered
by the user is too different from the gas concentration actual measured
value at the time. This is to prevent the accidental recalibration of the
analyzer to an out-of-range response curve.
EXAMPLE: The span set point is 80 ppm and the measurement response
is only 5 ppm. Section 7 describes this in detail.
Why does the analyzer not
respond to span gas? There are several reasons why this can happen. Section 10.3.2 has some
possible answers to this question.
Can I automate the calibration of
my analyzer? Any analyzer with zero/span valve or IZS option can be automatically
calibrated using the instrument’s AutoCal feature.
What do I do if the concentration
on the instrument's front panel
display does not match the value
recorded or displayed on my data
logger even if both instruments
are properly calibrated? This most commonly occurs for one of the following reasons: (1) a
difference in circuit ground between the analyzer and the data logger or a
wiring problem; (2) a scale problem with the input to the data logger. The
analog outputs of the analyzer can be manually calibrated to compensate
for either or both of these effects, see Section 6.13.4; analog outputs are
not calibrated, which can happen after a firmware upgrade (Section 6.13.5).
How do I measure the sample
flow? Sample flow is measured by attaching a calibrated flow meter to the sample
inlet port when the instrument is operating.
 For the 9110TH in its basic configuration, the sample flow should be
290 cm³/min 10%.
 For the 9110TM in its basic configuration, the sample flow should be
250 cm³/min 10%.
See Table 9-3 for more detailed information about gas flow rates.
Section 7 includes detailed instructions on performing a check of the
sample gas flow.