Siemens Servo Ventilator 300, Руководство по обслуживанию

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16 Siemens-Elema AB E382 E380E 061 01 03 01
Introduction Servo Ventilator 300/300A
1
In addition to the main forward path,
compensating elements are added as
described in both inspiratory feedback
control system pictures. The compensating
elements in this system works as follows:
• Using the input information of
ACTUAL
SUPPLY PRESSURE VALUE
and
DESIRED GAS FLOW
VALUE
the
VALVE POSITION CALCULATOR
directly
generates a rough approximate
POSITION
VALUE
which helps to obtain the desired
position within minimum time.
• The input information of
ACTUAL SUPPLY
PRESSURE VALUE
is used (inverted and
adequatly scaled) to create one small part
of the
DESIRED CURRENT VALUE
. This small part
of the
DESIRED CURRENT VALUE
will – in
combination with the opening force of the
INSPIRATORY VALVE
implied by the pressure of
the supplied gas – help to balance the
closing force on the
INSPIRATORY VALVE
implied by the mechanical spring inside
the
VALVE SOLENOID
even in closed position
of the
INSPIRATORY VALVE
.