Honeywell Searchline Excel, Техническое руководство

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64
MAN0530 Issue 10 - 11/09 Searchline Excel
2104M0506
5. PROBLEM SOLVING
Fault/Problem Causes Remedies
No signal or Receiver misaligned
Re-align the Receiver, first using the
very low signal telescope and then using the Interrogator.
at Receiver
Transmitter misaligned Re-align the Transmitter using the telescope.
The beam path has become Check that the beam path is clear from
obscured Transmitter to Receiver.
Remove any obstruction if present.
No output from Transmitter
1) Check that the Transmitter is flashing.
Alternatively, listen for a distinct ticking
sound when the lamp flashes.
Note: The infrared beam is invisible and eye
safe.
2) If the Transmitter is not flashing, check
that the +24V supply is reaching the
Transmitter correctly.
Unit does not Plastic test filters are only
Searchline Excel units are calibrated on
respond exactly an approximate simulation of gas real gas. This results in a variation of the
as expected to response
test filters
of different Excel
units to plastic test filters. See section
5.1.2.
1) Check that the response to the test
filters is within the limits stated in this
handbook. See section 5.1.2.
2) Check that the value being used for
response testing corresponds correctly to the
target gas that the unit has been calibrated for.
Receiver misaligned 1) Use the telescope and Interrogator to
optimise Receiver alignment.
2) Re-zero unit.
Contamination of windows 1) Check the Transmitter and Receiver
windows for build up of contamination.
Clean windows if required. See Chapter 5 .
2) Re-zero unit.
Drift of unit’s zero position 1) Verify that there is no gas in the beam path.
2) Re-zero the unit.
Unit appears to Misinterpretation of iNhibit, Searchline Excel does not report
be reporting a beam-bloCK or loW negative gas readings on the 4-20mA.
negative gas siGNalcurrents that are
1) Configure controller/PLC to interpret
reading on the output on the 4-20mA and present currents below 4mA correctly,
4-20mA or
,
2) Familiarise operators with the
interpretation of sub-4mA output currents
from Excel as follows:
FAULT 0mA
INHIBIT 2mA
BEAM-BLOCK 2.5mA*
LOW SIGNAL 3mA*
or,
3) Reconfigure the
INHIBIT , BEAM-BLOCK
and LOW SIGNAL currents output by the
Excel unit.