Sun Microsystems DGA 5000, Руководство оператора

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6.4 HC Residue Check
A HC residue check will follow every initial or manually triggered zero-
calibration.
The HC residue check will be aborted or postponed if a maintenance
function is selected (e.g. in order to perform a leak check) The residue
check will be resumed when the maintenance function is exited.
The HC residue check lasts a minimum of 20 seconds with no upper
time limit. During the check the unit will:
- Display the HC Residue Check pop-up window.
- Determine the concentration of hydro-carbons present in the gas
circuit. If a concentration greater than 20 ppm is found the pop-up
window will continue to be displayed and all measurements will
be blocked until the concentration of HC present in the analyser
has fallen to within the acceptable limits.
The sample probe must not be allowed to remain in the vehicle
exhaust tailpipe during the HC residue check. A concentration of
more than 0.5 % vol. co2 detected during the check indicates that
vehicle exhaust gases are being drawn into the unit. The program
will prompt the operator to remove the sample probe from the
tailpipe and all measurements will be blocked until this has been
done.
As ambient air is drawn through the gas circuit, the concentration of HC
should fall. If the residue has not fallen to within acceptable limits within
a reasonable time (1
– 2 minutes), the sample hose and probe should be
cleaned in accordance with the instructions contained in 9
.6: „Routine
Maintenance Procedures‟
and the zero-calibration procedure repeated.
If the concentration of HC does not fall to within acceptable limits after
the sample hose and probe have been cleaned the HC residue check
pop-up window will continue to be displayed. Switch the unit off and back
on in order to reset the machine. Repeat the calibration and HC residue
check procedure. If the concentration of HC is still too high, service is
required. Contact your SUN service centre or dealer.
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C H A P T E R 6