Teledyne 6200E - Sulfides Analyzer - Manual (Page 248)

TROUBLESHOOTING & REPAIR Model 6200E Instruction Manual
248 M6200E Rev: A1
11.3.2. No Response
If the instrument shows no response (display value is near zero) even though sample gas is
supplied properly and the instrument seems to perform correctly,
• Confirm response by supplying H
2
S span gas of about 80% of the range value to the
analyzer.
• Check the sample flow rate for proper value.
• Check for disconnected cables to the sensor module.
• Carry out an electrical test with the ELECTRICAL TEST procedure in the diagnostics
menu, see Section 6.9.6. If this test produces a concentration reading, the analyzer’s
electronic signal path is working.
• Carry out an optical test using the OPTIC TEST procedure in the diagnostics menu, see
Section 6.9.5. If this test results in a concentration signal, then the PMT sensor and the
electronic signal path are operating properly. If the M6200E passes both ETEST and
OTEST, the instrument is capable of detecting light and processing the signal to produce a
reading. Therefore, the problem must be in the pneumatics, optics or the UV lamp/lamp
driver.
11.3.3. Unstable Zero and Span
Leaks in the M6200E or in the external gas supply and vacuum systems are the most common
source of unstable and non-repeatable concentration readings.
• Check for leaks in the pneumatic systems as described in Section 11.5.1. Consider
pneumatic components in the gas delivery system outside the M6200E 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.
• Once the instrument passes a leak check, do a flow check (Section 11.5.2) to make sure
that the instrument is supplied with adequate sample gas.
• Confirm the UV lamp, sample pressure and sample temperature readings are correct and
steady.
• Verify that the sample filter element is clean and does not need to be replaced.
11.3.4. Inability to Span - No SPAN Key
In general, the M6200E will not display certain keyboard choices whenever the actual value of a
parameter is outside of the expected range for that parameter. If the calibration menu does not
show a SPAN key when carrying out a span calibration, the actual concentration must be outside
of the range of the expected span gas concentration, which can have several reasons.
• Verify that the expected concentration is set properly to the actual span gas concentration
in the CONC sub-menu.