Siemens KION Service Manual page 34

Description of functions
10. PC 1737 Measuring
Collects, converts and distributes measured patient
related values (expiratory flow, O
airway pressure, gas supply pressures). The values
are collected and distributed to other subsystems via
the CAN bus.
Detect patient related alarms and informs the ALA
subsystem. Alarm limits are either constant values or
values set on the control panel.
PC 1737 M
EASURING
executes the MEA-software stored in the exchang-
able MEA-PROM.
The main functions are:
3
• Expiratory flow measuring
• Insp. and Exp. pressure measuring
• Gas supply pressure measuring.
Expiratory flow measuring
The measured expiratory flow value is generated by
the E F
XPIRATORY LOW
The signal is pre-amplified to a level of 0 – 9 V (9 V =
180 l/min) on PC 1750 T
signal Exp. flow is supplied to PC 1737 M
To prevent offset in the flow signal, zeroing is done
when insp. and exp. time signals have the same
status.
The exp. flow signal is then amplified in two different
levels:
x 0.5 if the exp. flow is 18 – 180 l/min.
x 5 if the exp. flow is 0 – 18 l/min.
Both amplifiers works continuously, but only one of
the amplified signal is selected and used by the
processor.
Heating of the E
XPIRATORY
trolled by PC 1750 T
/ 6W, is moulded into the transducer housing and is
used for heating of the flow transducer.
The transducer is heated to approximately 40
(104 F) to prevent condensation of water vapour.
o
3 - 16
concentration,
2
contains a microprocessor that
T in the P
RANSDUCER ATIENT
. The pre-amplified
RANSDUCER
EASURING
F T is con-
LOW RANSDUCER
. A resistor, 220 Ohms
RANSDUCER
Insp. and Exp. pressure measuring
PC 1750 T
RANSDUCER
transducers for airway pressures. The signals from
the expiratory and the inspiratory pressure
transducers are pre-amplified on PC 1750. The
amplified signals, Exp. pressure and Insp. pressure,
are supplied to PC 1737 M
The signals are compared to the set upper pressure
limit and used to activate the upper pressure alarm.
There are two different controls of the upper
pressure alarm, one SW detected and one HW
detected. The pressure is supervised primarily by the
SW, but there is also a HW detection at +5 cmH20
above the set upper pressure limit.
• SW detection: When the INSP or EXP pressure is
higher than set upper pressure limit, CON orders
the SW to evacuate the system and disable the gas
modules. CON also reads the HW signal
PRESSURE_ERROR.L from MEA as a backup
detection.
• HW detection: When the INSP or EXP pressure is
+5 cmH2O above the set upper pressure limit, the
Upper pressure monitoring HW-block on PC 1737
C .
ASSETTE
sets the signal PRESSURE_ERROR.L low and
thereby cuts the +24 V power supply to all valves
in the system.
.
The following valves are disabled (both SW- and HW-
detection):
• All three G
AS
• I F
NSPIRATORY
• All M
USHROOM
• PEEP V
ALVE
Gas supply pressure measuring
Hospital central gas supply:
Pressures in the connected gases are measured by
the pressure transducers on PC 1720 W
The signals are amplified and supplied to PC 1737
M . The amplifiers on PC 1720 are factory
EASURING
calibrated.
C
o
Backup gas supply:
Pressure in the connected gas cylinders are
measured by the pressure transducers in the B
G S M
AS UPPLY
M .
EASURING
Siemens-Elema AB
is equipped with pressure
.
EASURING
M are closed
ODULES
G V is closed
RESH AS ALVE
V except MV5 are opened
ALVES
is opened.
. The signal is supplied to PC 1737
ANIFOLD
E382 E392E 061 01 02 02
KION / KION-i
P .
ALL RESSURE
ACKUP