Thermo Scientific 43i, Инструкция по эксплуатации

Страница: 143 / 312

Troubleshooting
Troubleshooting Guides
Thermo Fisher Scientific Model 43i Trace Level-Enhanced Instruction Manual 6-3
Table 6–2. Troubleshooting - Calibration Failures
Malfunction Possible Cause Action
Cannot zero instrument or
there is a high background
signal when sampling zero
air. (Zero air should
produce a reading
equivalent to less than
10.0 ppm SO
2
.)
Zero air system is faulty,
needs new SO
2
scrubbers or requires
maintenance.
Test against an ultra-zero cylinder
from a reputable scientific gas
supplier or check effect of a new
chromatography grade activated
charcoal scrubber installed at the
instrument inlet.
Zero air flow rate is
inadequate. Check by-pass or atmospheric
pressure vent to verify that the zero
air system is providing more flow
than the instrument is drawing.
Instrument is not
drawing in span gas. Check sample Flow and Pressure
readings on the Diagnostics screen.
Use an independent flow meter to
check flows at the sample inlet and
exhaust bulkheads (they should
match).
Perform a leak test, as described in
the “Preventive Maintenance”
chapter.
Span gas containing
SO
2
, NO, or a
hydrocarbon is
contaminating system.
Verify that span gases connected to
the calibration system are shut off
and leak-tight.
Internal or external
lines, filters, and other
sample handling
equipment are
contaminated or dirty. Replace inlet filter (if installed) and
as much of the tubing as possible.
Hydrocarbon kicker has
failed. Replace the hydrocarbon kicker.
High scattered light Go to Instrument Controls, select
Flash Lamp and toggle to OFF. If the
previously high signal drops to zero or
less when the flash lamp is off, the
problem may be caused by scattered
light from dust in the optical bench. If
so, carefully clean the optical bench.
Input board failure Disconnect the input board from the
interface board by unplugging ribbon
cable labelled “INPUT.” The
instrument reading should drop to
zero or to a negative value.
Instrument appears to
zero, but there is weak or Span cylinder empty Check the source pressure.