Thermo Scientific Sarasota SG901, Руководство пользователя

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Thermo Fisher Scientific Sarasota SG901 User Guide
7-1
Chapter 7
Troubleshooting & Service
This section provides troubleshooting steps for the analyzer.
Table 7–1. Fault diagnosis
Symptom Possible Problem / Solution
Condensation indicated by
large variations in density or
instrument failing to read
density.
1. Condensation may be due to gas cooling on pressure
reduction through the regulator. This can be minimized by
reducing the flow rate or reducing the pressure at the
sample point, since ambient heat will be better able to
warm the gas stream and evaporate any condensation in
the sample tubing. If excessive cooling is a problem, a
heat trace is advisable.
2. Check the filter.
3. If the density meter alarm activates:
- Check the filter for condensate.
- Close the isolating valve and purge the system via the
calibration tee until a density reading is obtained which
is correct for the gas used.
Note: If purging fails, clean the density meter as
described in its manual and replace the filter.
Flow rate/system response
time is too long or is
unstable.
1. Large changes in pressure of the inlet or exhaust may
affect flow rate and system response. If the process
conditions have been altered, adjust flow at the
regulating valve. If the exhaust pressure is unstable, a
back pressure regulator may be considered.
2. If the inlet pressure has been increased or is very high, a
pre-regulator at the sample point will decrease the
standard volume held in the sample transport line and,
therefore, the amount of gas that has to be transported to
the instrument, improving sample delay time.
Alarms raised by control room
type density converter.
Various alarms can be raised by the density converter. If the
converter is a control room type, typical alarms include:
- Density / Pressure too low: The pressure regulation has
failed or filters may be blocked, pressure is too low,
density is too low.
- Density / Pressure too high: The pressure regulation has
failed, or the exhaust return pressure is too high.
- Temperature too high / too low: PT100 failure. This
alarm may also indicate a process problem.
Fault Diagnosis