Siemens Servo Ventilator 300, Service Manual

Page: 72 / 131

70 Siemens-Elema AB E382 E380E 061 01 03 01
Description of functions Servo Ventilator 300/300A
2
12 Inspiratory pressure
The function of this main block is to
measure the pressure in the 11
INSPIRATORY
CHANNEL
and generate a corresponding signal
INSP
.
PRESSURE
via the board PC 1607
PNEUMATIC INTERCONNECTION
(N24:C7) to the
main blocks 4
MONITORING
and 6
REFERENCE
&
TIMING
.
12.1 Bacteria filter
This filter protects the 12.2
PRESSURE
TRANSDUCER
on the board 12.3
PRESSURE
AMPLIFIER
from contamination.
Service interval 3000 h of operation for
exchange of the inspiratory pressure
BACTERIA
FILTER
.
12.2 Pressure transducer
This differential
PRESSURE TRANSDUCER
is an
integrated part of the board 12.3
PRESSURE
AMPLIFIER
mounted together with a silicon
rubber connection piece. It refers the
pressure to ambient pressure and gives a
linear measurement in the range –20 cm H
2
O
to +120 cm H
2
O.
Pressure exceeding ±200 cm H
2
O must be
avoided.
12.3 Pressure amplifier
This board PC 1611 contains:
• a pressure transducer
• a generator of +5
V REFERENCE VOLTAGE
• an amplifier for the pressure signal
• the two potentiometers for calibration of
zero offset and gain.
When calibrated according to the Operating
Manual, chapter Calibration, the
PRESSURE OUT
signal (P24:C7) will have a scale factor of
75 mV/cm H
2
O.