Datex-Ohmeda CAPNOMAC ULTIMA, Руководство по обслуживанию

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CAPNOMAC ULTIMA
TM
SERVICE MANUAL
6-16
Strong drift of CO
2
,
N
2
O and AA
Fluid or dust in measuring bench.
Electrical connections to IR lamp faulty.
Loose screws in measuring unit. AGC circuit faulty (ACX
measuring board).
Strong drift of O
2
Blocked O
2
reference flow.
Uneven sample pump function. Replace pump.
Sudden increase in
gas display
Measuring cgamber contamination.
+/-15 V missing (fault in the power supply).
The above occurs
frequently Water trap malfunction. Check all internal tubing and the interior
of the water trap for occlusions or leaks. Replace water trap.
Check flow rates.
CO
2
/N
2
O/AA
software calibration
fails
Analog gains out of range. Check the general functioning of the
measuring electronics.
O
2
software
calibration failure
‘Calibrating gas
sensor’-message
remains on the
screen
Adjust the gain trimmer of O
2
measuring unit. If not possible,
replace the measuring unit.
CO
2
/N
2
O gas analog voltages out of range (over about 9 V).
Measuring chamber contamination or failure on measuring unit
electronics or on measuring board.
Impossible to adjust
gain AGC malfunction, Check analog switches and A4.
False reference voltage.
Faulty temperature compensation circuit.
Too low response in
both CO
2
, N
2
O, and
AA (and possibly
O
2
)
Leak in water trap, or tubing between the trap and the measuring
units; the sample is diluted with air.
Abnormally high
response to all gases
(or abnormally low)
or sudden occlusion
warning Pressure transducer failure on ACX measuring board (check Pout
voltage).
Random output
(resembling noise) Timing pulses out of sync. Check timing pulses from photometer,
pulse shaping circuit, and logic circuitry on the measuring board.
Chopper motor not running
Motor faulty or connection loose.
Driver transistor C-E open circuit or current limiter short circuit.
January 15th, 1997/6