Datex-Ohmeda CAPNOMAC ULTIMA, Service Manual

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CAPNOMAC ULTIMA
TM
SERVICE MANUAL
7-2
7.2 Gas sampling system adjustment
Flow rates should be measured and possibly adjusted under the
following conditions:
After any part within the sampling system has been
replaced
Gas response is slow
NOTE:
Before adjusting the flows replace the D-FEND
TM
water trap if necessary.
NOTE:
Let the monitor warm up for 30 minutes before
measuring flow rates.
For the flow rate measurements a flowmeter with a low flow
resistance and capability to measure low flow rates is required.
When making measurements a normal length of sampling line has
to be connected to the monitor as it has a considerable effect on
the flow.
The flow rates are adjusted by changing the flow resistance
cassettes (constriction cassettes) in the sampling system. See Table
5.2 for the alternative cassettes.
The adjustments and the respective constrictions to be adjusted are
shown in Figure 7.1.
FLOW RATE
If any flow rates are not correct, first replace the D-FEND
TM
water trap. Then recheck the incorrect flows before adjusting the
flow rates.
Total flow rate is measured by rotameter at the sampling line. The
rate should be between 180 and 220 ml/min. The flow rate is
adjusted by changing the constriction cassette which is located
behind the pump (No. 22).
Rate of the side flow is checked by blocking the side flow after
the water trap and measuring the flow rate as above. The rate
should decrease by 10 to 26 ml/min.
January 15th, 1997/6