Dräger Carina Instructions For Use Manual page 143

Operation with controlled expiratory valve (4): dur-
ing inspiration the pressure in the pilot line closes
the expiratory valve. During expiration the pressure
drop in the pilot line opens the expiratory valve to
discharge the expiratory air.
Operation with leakage valve (5): the expiratory air
of the patient is discharged through the leakage
valve.
Oxygen admixture HPO
The desired FiO value can be set in the menu. The
2
O is fed in via the high-pressure O
2
oxygen passes through a filter (F5) that removes
impurities that could adversely affect the operation
of the downstream components. The oxygen enters
the electrically controlled O
(V5), which controls the O
passes into the O measuring unit (7) through a
2
venturi (R4). The resulting pressure differential is a
control parameter for the O
the O flow sensor (DPS3) and the result is used to
2
regulate the O proportional valve (V5). The admix-
2
ture to ambient air is in the turbine (2).
Oxygen admixture LPO
The system is switched to low-pressure oxygen in
the menu. Oxygen is fed in through the low-pres-
sure oxygen inlet (8). The oxygen passes through a
filter (F6) that removes impurities that could ad-
versely affect the operation of the downstream
components. The oxygen enters the electrically
controlled O proportional valve (V5), which is fully
2
opened for operation with low-pressure oxygen.
The O flow is not regulated. The admixture to am-
2
bient air is in the turbine (2).
Check valves
The check valves (CV6 and CV8) prevent oxygen
from escaping from an unused O
valves also prevent high-pressure oxygen from
flowing to the low-pressure O
sources are connected at the same time. One
check valve (CV9) restricts the pressure in the low-
pressure O inlet to <1 bar by discharging excess
2
oxygen to the ambient air.
Instructions for use Carina SW 3.2n
inlet (9). The
2
proportional valve
2
flow. The oxygen
2
flow. It is measured by
2
inlet. The check
2
source if both
2
Safety
All sensors are duplicated and are monitored inde-
pendently. A sensor failure triggers an alarm mes-
sage and automatically switches the device to
emergency ventilation, see "Emergency ventila-
tion" on page 103.
Safety valves
The safety valve (overpressure) (CV3) restricts the
airway pressure to 60 mbar (or hPa or cm H
The emergency breathing valve (underpressure)
(CV2) restricts the airway pressure to –3 mbar (or
hPa or cm H O).
2
Principles of operation
O).
2
143