GE b30, Technical Reference Manual

Page: 214 / 252

B30 Patient Monitor
8-14
Document no
.
2044677-001
"
6. Flow measurement offset
Enter the service menu
Gases :
Gas Unit - Gases
Check that the flow measurement offset, i.e. the shown sample Zero value is within ±10
ml/min.
"
7. Ambient pressure
Check that the shown Ambient value corresponds with the current ambient pressure (±20
mmHg).
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8. Zero valve check
Feed calibration gas and check that the gas readings in the service menu correspond
with the values on the gas bottle sticker. Keep feeding gas, then activate the zero valve
from the menu. The CO
2
reading should drop back to near 0%.
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9. Nafion tube
Replace the Nafion tube, if necessary
.
NOTE: The Nafion tube should be replaced annually.
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10. Leak test
Perform the sampling system leak test.
Connect a flow cassette with high flow resistance value (50/1.1) to the end of the
sampling line and start following the Amb-Work value in the service menu. When the
value exceeds 130 mmHg, connect the other port of the flow cassette to the sample gas
out connector and switch off the pump.
Wait until the pressure inside the sampling system is stabilized, then observe the shown
Amb-Work value. The value, i.e. the pressure inside the sampling system should not drop
more than 6 mmHg in 20 seconds.
If the pressure drops more, first check the connections and repeat the test.
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11. Check the flow rates
Wait until the Sample Flow value returns close to 150 ml/min.
Connect a flow meter to the 3 meter sampling line and check that the flow (the flow meter
reading) is within the following range: