Siemens Servo Ventilator 300 - Page 63

Servo Ventilator 300/300A Description of functions
E382 E380E 061 01 03 01 Siemens-Elema AB 61
2
7 Inspiratory control
This main block consists of the board
PC 1616 INSPIRATORY CONTROL including its
MICROPROCESSOR MODULE PC 1588.
7.1 Mixer CPU including MIX-
PROM functions
This block includes the board PC 1588 with
a MIX-PROM. Some details of the Micro-
processor module PC 1588 are mentioned in
section General in this chapter. The MIX-PROM
function is a control function for the block
7.3 MIXER.
FLOW REF overrange
The overrange indication signal OVERRANGE.H
(going to the block 4.1 MONITOR/ALARM CPU) is
activated in case the level of the input signal
FLOW REF is above 9.9 V during more than
50% of the duration of one Inspiration time
or during more than 200 ms.
Since the scale factor of the FLOW REF signal
is 3/18/45 V/l/s (Adult/Pediatric/Neonate) this
implies a limit value for the flow reference
signal FLOW REF concerning overrange
indication as shown in the following table:
7.2 Inputs
This block is a multiplexor for input signals
to the main block 7 INSPIRATORY CONTROL.
Example of input:
• Front panel setting for O
2
concentration
(O
2
CONC SETTING).
7.3 Mixer
Input signals used in this block are:
• O
2
CONC SETTING (From main block 1 FRONT
PANEL
)
• One of the two flow reference signals
(from main block 6 REFERENCE & TIMING)
Controlled by the block 7.1 MIXER CPU the
flow reference signal in use is split up into
partial flow reference signals used in the
main blocks 8 INSPIRATORY VALVE UNIT – AIR and
9 INSPIRATORY VALVE UNIT – O
2
:
• AIR FLOW REF and
• O
2
FLOW REF
The sum of these reference level signals
(internal signal TOT. FLOW REF) corresponds to
the flow reference input signal in use.
When the function Oxygen breaths is
activated – from main block 1 FRONT PANEL –
the O
2
CONCENTRATION value used for the split
up of the flow reference signal in this block
7.3 MIXER is 100% during 20 breaths or
during 1 minute (whichever represents the
shorter time).
egnartneitaP
gnittes
noitidnocegnarrevO
tludA
WOLFFER s/l3.3>
cirtaideP
WOLFFER s/l55.0>
etanoeN
WOLFFER s/l22.0>