8 troubleshooting> 8-1, 8 troubleshooting – Yokogawa Extractive Oxygen Gas Analyzer TDLS220 User Manual
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<8 TROUBLESHOOTING> 8-1
IM 11Y01B02-01E-A 4th Edition September 11, 2012-00
8 Troubleshooting
The TDLS220 TDL Analyzer troubleshooting is fairly simple for a process analyzer. First, virtually all
components used in the system have a long Mean Time Between Failures (MTBF) with rated life of
components typically exceeding 10 years (when operating within their stated specifications). Second,
most probable failures and problems are diagnosed by the system, generating internal warning and fault
conditions.
The intent of this guide is to provide common troubleshooting steps, it does not detail specific repair
procedures (such as laser module replacement), as these are unlikely and are detailed in other sections
of the manual. Routine maintenance procedures are also detailed in other sections of the manual.
The most common issues are divided into two categories:
•
Warnings. These are conditions which will affect the analyzer reading but not cause complete
loss of measurement integrity. An example would be reduction of transmission (amount of laser
power at the detector) which could indicate window fouling, where the measurement is still
being made, but further loss of transmission will cause loss of measurement.
•
Faults. These are conditions where the measurement is lost, or degraded past the point of
reliability. An example would be loss of transmission, which could indicate complete miss-
alignment or laser failure.
The TDLS220 system will diagnose many common warnings and faults, taking the following actions:
•
The analyzer generates a status flag that is displayed on the main screen; if only one warning/
fault is present the system will display this on the screen. The “ACTIVE ALARM” menu selection
will allow the user to view all active Warnings and Faults
•
The system will log the warning/fault in a log file along with a description, time-triggered and
time-cleared.
•
The 4-20mA signal can change to 3.3mA (or 20ma) under a fault or warning condition (user
changeable).
•
The digital output of the analyzer will trigger (Channel 1 – Warnings, Channel 2 – Fault, Channel
3 – Concentration or Transmission)
•
The analyzer will capture spectra for diagnostic assistance
•
The Results file will indicate a Warning (1) or Fault (2) in the continuous Results file