Penlon AV-S, Service Manual, Page: 18 / 94

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1
4
DESCRIPTION
3. End of
Expiratory Phase
With the bellows at the top
of its housing fresh gas
continues to flow. To
prevent a high pressure
build up the exhalation
diaphragm (5) lifts and
allows gas to exit through
the exhaust valve (4).
4. PEEP
Positive End
Expiratory
Pressure
(user selectable)
During PEEP the Exhalation
Proportional valve (3)
applies PEEP pressure plus
20 cmH2O to the exhaust
valve, which remains closed
at this stage.
As fresh gas flows in the
patient circuit, any pressure
increase above PEEP
pressure in the bellows will
cause gas to bleed past the
exhaust valve (4).
A continuous flow from the
Inspiratory proportional
valve (1) ensures that any
fall in pressure is
compensated by driving the
bellows as required.
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5
4