Siemens Servo i User manual

Servo…
Service Manual
E382 E407E 061 01 01 02

Siemens-Elema AB
Important Servo…
E382 E407E 061 01 01 02
1 - 2
Notes

E382 E407E 061 01 01 02 Siemens-Elema AB
Servo…Important
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Contents
1. Important .......................................................................................................
2. Introduction ...................................................................................................
3. Description of functions..............................................................................
4. Disassembling and assembling ................................................................
5. Service procedures......................................................................................
6. Troubleshooting............................................................................................
7. Preventive maintenance .............................................................................
8. Index ...............................................................................................................
9. Diagrams ........................................................................................................
1
2
3
4
5
6
7
8
Contents
9

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Important Servo…
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Important
General
• Service documentation for the Servo…™ Ventilator
System consists of:
– User's manual
– Service Manual
– Spare Parts List.
• Documentation for all optional equipment
included in the Servo…System is also available.
• The User's manual is an indispensable comple-
ment to the Service Manual for proper servicing.
• Serial number of the unit is found on a label
attached to the Patient Unit close to the supply
gas inlets.
• System version number can be found in the
Status window on the User Interface. Make sure
that the version of the User's manual corresponds
to this system version.
Text inside a box is used to highlight important
information.
• In addition to the Important information given
here and in the related documents (e. g. in the
User's manual), always pay attention to applicable
local and national regulations.
• Responsibility for the safe functioning of the
equipment reverts to the owner or user in all
cases in which service or repair has been done by
a non-professional or by persons who are not
employed by or authorized by Siemens, and when
the equipment is used for other than its intended
purpose.
• Data on internal pressures in the Servo…System
are given in Pa (bar).
Airway pressures are given in cm H2O (Pa).
1 hPa = 1 mbar 1 mbar = 1 hPa
1 kPa = 10 mbar 1 mbar = 0.1 kPa
1 kPa = 0.01 bar 1 bar = 100 kPa
1 kPa N10 cm H2O 1 cm H2O N0.1 kPa
1 kPa N0.01 at 1 at N100 kPa
1 kPa N0.01 kgf/cm21 kgf/cm2N100 kPa
1 kPa N0.01 kp/cm21 kp/cm2 N100 kPa
1 kPa N0.145 psi 1 psi N6.9 kPa
1
Hazard notices
• Before disassembling or assembling the Servo…
System, make sure that the:
– Gas supply is disconnected.
– Mains power cable is disconnected.
– On/Off switch is set to Off.
– Battery modules are disconnected.
– The Servo…System is cleaned according to
instructions in the User's manual, chapter
Routine cleaning and chapter Regular
maintenance, section Extended cleaning of insp.
channel.
• With power supply connected to the Servo…
System, there are energized electrical
components inside the unit. All personnel must
exercise extreme caution if fault tracing or
adjustments are performed with power supply
connected and with user interface and patient
unit covers removed.
Symbols used in this manual
•ESD sensitive components. Make
sure to take precautions to avoid
damaging ESD sensitive components.
•Special waste. Make sure to discard
worn-out batteries and other
disposable parts according to local
regulations and in an environmentally
acceptable way.
•Recycling. Recycle if possible.
Recycling facilities may not be
available in all areas.
•Technical training. Refers to the
Servo…Technical training supplied by
Siemens.
•Service contract. Refers to the
Servo…Service contract supplied by
Siemens.

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Servo…Important
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Important
To the responsible service personnel
• The contents of this document are not binding.
If any significant difference is found between the
product and this document, please contact
Siemens for further information.
• We reserve the right to modify products without
amending this document or advising the user.
• Only personnel trained and authorized by
Siemens shall be permitted to perform
installation, service or maintenance of
the Servo…System. Only Siemens
genuine spare parts must be used.
PC boards (spare parts) must always be kept in a
package for sensitive electronic devices. Siemens
will not otherwise assume responsibility for the
materials used, the work performed or any
possible consequences of same.
• The device complies to standards and require-
ments as stated in the Servo…Ventilator System –
User's manual.
Installation
• Only personnel trained and authorized
by Siemens shall be permitted to install
the Servo…System. The installation and
handing over procedures are described
in the ”Servo…Ventilator System –
Installation Instructions”.
Functional check
• After any installation, maintenance or service
intervention in the Servo…System, perform a
Pre-use check according to instructions in the
Servo…Ventilator System – User's manual.
Service
• The Servo…System must be serviced at
regular intervals by personnel trained
and authorized by Siemens.
Any maintenance or service must be
noted in a log book provided.
• It is recommended that maintenance
and service is done as a part of a service
contract with Siemens.
• Preventive maintenance must be performed at
least once every year as long as the unit is not
used more than normal. Normal operation is
estimated to correspond to approx. 5.000 hours
of operation. Details are found in this Service
Manual, chapter ”Preventive maintenance”.
• Worn-out batteries must be recycled or
disposed of properly according to local
regulations. Recycle facilities may not
be available in all areas.
• Batteries must not be disposed of with
ordinary waste. All other disposable
parts shall be discarded according to
local regulations and in an environmen-
tally acceptable way.
• When working with ESD sensitive
components, always use a grounded
wrist band and a grounded work
surface. Adequate service tools must
always be used.
1

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Environmental declaration
Purpose
This environmental declaration is for a Servo…basic
unit including the carrier and one battery.
Letters codes within brackets refers to the
Functional Block Diagram in chapter Diagrams.
Components with special environmental concern
Components listed below shall be disposed of in an
environmentally safe way.
Printed circuit boards
• PC 1770 Main back-plane
• PC 1771 Control, including a Lithium battery (C)
• PC 1772 Monitoring, including Lithium battery (M)
• PC 1775 Plug-and-Play back-plane (P)
• PC 1777 Panel (U)
• PC 1778 Standard connectors & DC/DC (P)
• PC 1780 Pneumatic back-plane (I)
• PC 1781 Pressure transducer, 2 pcs (T)
• PC 1784 Expiratory channel (F)
• PC 1785 Exp. channel connector (E)
• PC 1786 Exp. channel cassette (E)
Other electronics
• TFT assembly including backlight (U)
• Touch screen (U)
•O
2cell, containing Pb (I)
• Air module, containing multiple PC boards (I)
•O
2module, containing multiple PC boards (I)
• AC/DC Converter, containing PC boards (P)
• Exp. valve coil (E)
• Safety valve pull magnet (I)
Construction materials
The construction materials used in Servo…in % of
the total weight.
Metal – total 77%
• Aluminium 70%
• Steel, zink, brass 8%
Polymeric material – total 9%
• PA (Polyamide)
• POM (Polyoxymethylene)
• SI (Silicone)
• TPE (Thermoplastic elastomer)
• PUR (Polyurethane)
• ABS (Acrylicnitrilebutadienstyrene)
• EPDM (Ethylenepropylenedienemonomer)
• PTFE (Polytetrafluoroethylene)
• FPM (Fluororubber)
• NBR (Nitrilerubber)
• PP (Polypropylene)
• PVC (Polyvinyl chloride)
• PS (Polystyrene)
Electronics – total 14%
• Accumulators Nickel Metalhydride
• Printed circuit boards, cables etc.
Others – very small amounts
• Sterile filter paper of glass fibre
Important
1

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Articles of consumption
1. Bacteria filter
2. Filters for the gas modules
3. Filter for the inspiration pressure transducer
4. Filter for the O2cell
5. Nozzle units for the gas modules
6. Expiratory cassette.
Item 1: Consumption approximately 250 pcs/year.
Items 2 – 5: Changed every 5000 hours.
Item 6: Changed when needed.
Power consumption
Normal use (no extra internal or external devices
used).
• On 60 W
• Stand-By 42 W
Important
Noise level
Less than 50 dBA.
Packing materials
The amounts of packing materials will vary
depending on customer adaptation.
Siemens-Elema is a member of the Swedish REPA
register (No. 5562378850).
Materials for packing:
• Loading pallet. Fulfils the USA requirements
7 CFR 319.40 May 25’th 1995.
• Corrugated cardboard
• Stretch film of Polyethylene, PE.
• Shock-absorbing material of expanded poly-
ethylene, EPE, or expanded polypropylene, EPP.
• Clamps of Polyethylene, PE.
1

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Important Servo…
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Notes
1

E382 E407E 061 01 01 02 Siemens-Elema AB
Servo…Introduction
2 - 1
2
2. Introduction
Main units.......................................................... 2 - 2
User Interface................................................. 2 - 3
Patient Unit .................................................... 2 - 4
Servo…software structure .................................. 2 - 7
General ........................................................... 2 - 7
Breathing ........................................................ 2 - 7
Monitor........................................................... 2 - 7
Panel .............................................................. 2 - 7
System ID ...................................................... 2 - 7
Only personnel trained and authorized by
Siemens shall be permitted to perform
installation, service or maintenance of the
Servo…System.
Make sure that the Servo…System is properly
cleaned before performing any service or
maintenance; routine cleaning as well as extended
cleaning. For cleaning procedures, refer to the
”Servo…Ventilator System – User's manual”.
Any service or maintenance must be noted in a log
book.
All disposable parts must be discarded according
to local regulations and in an environmentally
acceptable way.
After any service or maintenance of the Servo…
System, perform a ”Pre-use check”. Refer to the
”Servo…Ventilator System – User's Manual” for
details.

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Introduction Servo…
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2
Main units
The Servo…System is available in different main
configurations:
• Infant
• Adult
• Universal
These main configurations are as standard equipped
with a number of ventilation modes suitable for each
patient category. Further ventilation modes can be
installed via software option upgrades.
The Servo…System can be divided into the following
main units:
• User Interface
• Patient Unit
The Control cable connects the User Interface and the
Patient Unit.
These main units are mounted onto the Servo…Mobile
cart which is the main body of the system.
A number of optional equipment can also be
incorporated in the Servo…System. Examples on such
optional equipments are:
• Servo Ultra Nebulizer, Servo….
• Servo…Holder for the Patient Unit.
• Gas trolley for backup gas cylinders.
• Gas cylinder restrainer for backup gas cylinders.
• IV Pole, Servo….
• User Interface panel cover.
• Battery module, Servo….
• Support Arm 177.
• Servo Humidifier.
• Humidifier Holder, Servo….
Patient Unit
User Interface
Servo…Mobile Cart

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Servo…Introduction
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2
User Interface
The User Interface can be mounted onto the Mobile
cart but can also easily be removed from the cart and
mounted on the bed post or table/shelf. The User
Interface can be rotated and tilted into a suitable
position. Locking levers, mounting devices and some
other items are shown in the illustration above.
1. Loudspeaker
2. Cable reel
3. PC Card slot with slot cover
4. Locking arm, rotation
5. Locking screw, alternative mounting
6. Panel holder
7. Control cable
8. Connection for PC, service port
9. On/Off switch
10. Locking arm, tilting.
For further information regarding the User Interface
controls, refer to the User's manual.
When the front panel section is removed from the
rear cover, the following parts are accessible:
• Touch screen assembly, front cover frame included.
• TFT Display including lamps.
• PC board Backlight inverter.
• PC 1777 Panel including PC Card slot.
• Loudspeaker.
• Main rotary dial (rotary encoder with switch).
• Direct access controls (rotary encoder).
SVX9100X
Loudspeaker TFT Display
PC 1777
Panel
PC Card-
slot
Main rotary
dial
Direct access
controls
Backlight
inverter
Touch screen
assembly

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Introduction Servo…
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2
Patient Unit
The Patient Unit can be rotated on and pulled out of
the Servo…Mobile cart. It can also be removed from
the Mobile cart and mounted onto a Servo…Holder.
Items accessible from the outside of the Patient Unit
are shown in the illustration above.
1. Handle.
2. Gas inlet for Air.
3. Gas inlet for O2.
4. Equipotentiality terminal.
5. Mains supply connector incl. fuses F11 and F12.
6. Internal fan with filter.
7. Connector for external +12V DC power supply.
8. Fuse F1 for external +12V DC power supply.
9. Optional connector.
10. Connection to the User Interface control cable.
11. 9-pole serial port for data communication (RS 232).
12. Expiratory outlet.
13. Inspiratory section cover.
14. Expiratory inlet.
15. Module unit for connecting optional modules,
e. g. up to six Battery modules, Servo….
16. Connector for Servo Ultra Nebulizer Servo….
17. Inspiratory outlet.
18. Serial number label. The serial number stated on
this label is the ID number of the unit. This serial
number must always be refered to when ordering
service, spare parts, software updates/upgrades,
etc.

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2
When the Patient Unit front cover is removed, the
following parts are accessible:
• PC 1772 Monitoring.
• PC 1771 Control.
• PC 1784 Expiratory channel with the two connected
PC 1781 Inspiratory and Expiratory Pressure
Transducers.
• Expiratory valve coil.
• Plug-and-Play Module incl. PC 1775 Plug-and-Play
back-plane.
• AC/DC Converter.
• Internal fan.
• Mains supply inlet.
• PC 1778 Standard connectors & DC/DC.
• The PC boards, as listed above, are connected to
the PC 1770 Main back-plane.
• The gas modules, the O2cell and the safety valve
pull magnet are connected to the PC 1780 Pneu-
matic back-plane.
Plug & Play
Module incl.
PC 1775
Plug and Play
back-plane
PC 1778
Standard
Connectors
& DC/DC
SVX9101X
PC 1771
Control
PC 1784
Expiratory
channel
Expiratory
valve
coil
AC/DC
Converter
PC 1772
Monitoring
Internal
fan
Mains
supply
inlet
PC 1781
Exp. press.
transducer
PC 1781
Insp. press.
transducer
SVX9118X
PC 1770
Main back-plane
PC 1780
Pneumatic back-plane

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Introduction Servo…
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2
The upper part of the Patient Unit contains the
inspiratory section and the expiratory section.
The main parts of the inspiratory section are the:
• Two gas modules, Air and O2, for regulation of the
inspiratory gas.
• Connector muff.
• Inspiratory pipe with housings for the O2cell and for
the safety valve.
•O
2cell incl. bacteria filter.
• Temperature sensor.
• Inspiratory pressure transducer tube incl. bacteria
filter, to connect the inspiratory pressure
transducer.
The main parts of the expiratory section are the:
• Expiratory cassette.
• Expiratory valve coil.
The expiratory cassette is a complete unit and must
not be disassebled. It contains the following parts:
• Expiratory inlet with moisture trap.
• Ultrasonic flowmeter.
• Heating foil to keep a stable temperature in the
expiratory gas.
• Pressure transducer connection, incl. bacteria filter,
to connect the expiratory pressure transducer.
• Expiratory valve incl. valve membrane.
• Expiratory one-way valve.
The expiratory valve coil, mounted under the
expiratory cassette compartment, controls the valve
membrane in the cassette.
SVX9120X
Gas
modules
Connector
muff
O2cell incl.
bacteria filter
Safety valve
Insp. pressure transducer
tube incl. bacteria filter
Temperature
sensor
Inspiratory
pipe
Expiratory cassette
SVX9122X

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2
General
The Servo…software installed in the ventilator will
contain all available system functionality. The soft-
ware is separated into different subsystems and
stored on some of the PC boards. The separation of
the software is handled by the installation program.
The Servo…software is divided into the following
software subsystems:
• Breathing
• Monitor
• Panel
• System ID
Breathing
The Breathing S/W controls the delivery of gases to
the patient. This subsystem is responsible for the
breathing system, that is:
• Ventilation control and regulation
• Inspiratory channel
• Expiratory channel
• Nebulizer control (software option)
The Breathing S/W is stored on PC 1771 CONTROL and
PC 1784 EXPIRATORY CHANNEL. New software can be
installed via a System software update. The system
software must be re-installed if PC 1771 or PC 1784
is replaced.
The Breathing S/W is executed by microprocessors
on PC 1771 and PC 1784.
Monitor
The Monitor S/W controls all monitoring and alarm
functions in the system, including trends of measured
values. Events, such as alarms and change of settings
will also be logged.
The Monitor S/W is stored on PC 1772 MONITORING.
New software can be installed via a System software
update. The system software must be re-installed if
PC 1772 is replaced.
The Monitor S/W is executed by the microprocessor
on PC 1772.
Panel
The Panel S/W controls all user interaction, as well as
software updating to all subsystems via the PC Card-
interface.
The Panel S/W is stored on PC 1777 PANEL. New
software can be installed via a System software
update. The system software must be re-installed if
PC 1777 is replaced.
The Panel S/W is executed by the microprocessor on
PC 1777.
System ID
A configuration file, the System ID S/W that is unique
for each ventilator, will enable the functions selected
for this ventilator. The System ID S/W will be
upgraded if the configuration of the ventilator is
changed.
The System ID S/W is stored on PC 1770 MAIN BACK-
PLANE. New System ID S/W can be installed via an
Option upgrade.
PC1777 PANEL
PC1784
PC1771
PC1772
PANEL S/W
MONITOR S/W
BREATHING
S/W
SVX9143X
PC1770
SYSTEM ID
S/W
Servo…software structure

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Introduction Servo…
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2
Notes

E382 E407E 061 01 01 02 Siemens-Elema AB
Servo…Description of functions
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3
3. Description of functions
About this chapter ............................................. 3 - 2
Memory types used in the Servo… ..................... 3 - 2
User Interface .................................................... 3 - 2
User Interface controls ................................... 3 - 2
PC 1777 Panel ................................................ 3 - 2
Loudspeaker ................................................... 3 - 2
Backlight Inverter ........................................... 3 - 2
Front panel screen ......................................... 3 - 2
Patient unit ........................................................ 3 - 3
Inspiratory section .......................................... 3 - 3
Expiratory section ........................................... 3 - 6
PC 1770 Main back-plane ............................... 3 - 7
Pressure transducers ..................................... 3 - 7
PC 1784 Expiratory Channel ........................... 3 - 8
PC 1771 Control ............................................. 3 - 8
PC 1772 Monitoring ....................................... 3 - 8
Power supply ................................................. 3 - 9
Module unit .................................................... 3 - 9
Internal fan ..................................................... 3 - 9
Optional PC board slots .................................. 3 - 10
Control cable ..................................................... 3 - 10
Only personnel trained and authorized by
Siemens shall be permitted to perform
installation, service or maintenance of the
Servo…System.
Make sure that the Servo…System is properly
cleaned before performing any service or
maintenance; routine cleaning as well as extended
cleaning. For cleaning procedures, refer to the
”Servo…Ventilator System – User's manual”.
Any service or maintenance must be noted in a log
book.
All disposable parts must be discarded according
to local regulations and in an environmentally
acceptable way.
After any service or maintenance of the Servo…
System, perform a ”Pre-use check”. Refer to the
”Servo…Ventilator System – User's Manual” for
details.

Siemens-Elema AB
Description of functions Servo…
E382 E407E 061 01 01 02
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3
About this chapter
This text refers to the Functional Main Blocks diagram
in chapter ”Diagrams”. Text written in SMALL CAPS
refers to block names in the Main Blocks diagram.
Memory types used in the Servo…
There are four different types of memories used in
the Servo…:
• Flash memory. For software storage. Can be
upgraded / updated via Option card or S/W version
update card. Present on PC 1771, PC 1772,
PC 1777 and PC 1784.
• RAM. For temporary storage of software and data.
Present on PC 1772 and PC 1777.
• Non-volatile memory. RAM with battery back-up.
For settings, trends and logs. Present on PC 1771
and PC 1772.
• EEPROM. For PC board information, configuration,
calibration data, etc. Present on almost all PC boards
and in the O2cell.
User Interface
Functional Main Blocks diagram marking: “U”
User Interface controls
Setting of different parameter input values is made
with the help of the following different interface
devices:
• Main Rotary Dial (rotary encoder with switch).
• Direct Access Control, 4 each (rotary encoders).
• Membrane buttons. Integrated parts of the Touch
screen assembly.
• Touch screen.
PC 1777 Panel
Some features included on PC 1777 PANEL are:
• SIMM (Single In-line Memory Module) mounted on
its connector P77. Memory type: SDRAM
• PC CARD SLOT intended for connection/insert of a PC
Card. PC Cards are used to:
– Download software into the different flash
memories situated on PC-boards marked mPand
into the EEPROM on PC 1770 MAIN BACK-PLANE.
– Transfer patient and system data for further
transfer to a computer.
– Service purpose.
• Microprocessor on this board includes control of the
functions of the USER INTERFACE.
• ID-PROM: The ID information can be read by the
Servo…System.
• On/Off switch: Switch to Power up or Power down
the Servo…System. Refer to section ”Power supply”.
• Connection for PC (P86): Ethernet port intended for
test and service purpose. Connected via a service
cable. For future options.
• Microphone used to monitor of sounds from the
Loudspeaker.
Loudspeaker
For generation of sound, e.g. alarm. Connected to
P72 on PC 1777 PANEL.
The loudspeaker generates different tones with
overtones, at different sound volume. The
loudspeaker is continuously supervised by the
microphone on PC 1777 PANEL.
Backlight Inverter
PC board with driving stage for backlight (lamps)
mounted behind the TFT Display. The supply voltage
delivered by the Backlight Inverter is 660 V.
The Backlight Inverter is connected to P73 on
PC 1777 PANEL.
Front panel screen
The front panel screen comprises:
• Touch screen assembly
• TFT Display
• Backlight.
The Touch screen implies the touch function of the
front panel screen and is interactive with information
displayed on the TFT Display. The front panel frame
with the touch screen, membrane buttons and DIM
sensor forms the Touch screen assembly and must
be handled as one complete part. The DIM sensor
measures the ambient light and the screen brightness
is automatically adjusted.
The TFT Display is a Thin Film Transistor Screen for
color display of picture- and alphanumeric data.
The Backlight consists of two fluorescent tubes
(lamps) mounted behind the TFT Screen. They are
driven from the BACKLIGHT INVERTER. Estimated lifetime
(with acceptable brightness level) for the lamps is
30.000 hours.

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3
Patient unit
Inspiratory section
Functional Main Blocks diagram marking: “I”
The main block INSPIRATORY SECTION conveys the
breathing gas from its gas inlets for Air and O2supply
to the patient breathing system. It comprises the
following main functions:
•GAS MODULES – AIR AND O2.
•CONNECTOR MUFF.
•INSPIRATORY PIPE.
•O
2CELL.
•TEMPERATURE SENSOR.
•INSPIRATORY PRESSURE TUBE.
•SAFETY VALVE.
•INSPIRATORY OUTLET.
• PC 1780 PNEUMATIC BACK-PLANE.
Gas modules – Air and O2
The Air and O2GAS MODULES regulates the inspiratory
gas flow and gas mixture.
1. Filter
2. Inspiratory valve temperature sensor
3. Supply pressure transducer
4. Flow transducer (Delta pressure transducer and net)
5. Nozzle unit with valve diaphragm
6. Inspiratory solenoid
The GAS MODULES are factory calibrated. Each GAS
MODULE must not be disassembled further than
described in chapter ”Preventive maintenance”.
Gas inlet
The gas inlet nipples are quick-couplings where gas
supply is connected to the ventilator. The design of
the inlet nipples and their color markings vary
according to the standard chosen.
Gas is to be connected from hospital central gas
supply or from gas cylinders. The Air supply may be
connected from a compressor for medical air.
Filter
The FILTER protects the ventilator from particles in the
gas delivered to the GAS MODULES. The filter must be
replaced during the ”Preventive maintenance”.
The filter housing and the filter cover are provided
with matching guide pins. These guide pins prevent
mounting of the filter cover (with gas inlet nipple) on
the wrong module.
A non-return valve for the gas inlet is located in the
filter cover. This valve will suppress short pressure
drops in the gas supply.
The non-return valve is also designed to slowly
evacuate compressed gas from the module, if the gas
supply to the module is disconnected.
Inspiratory valve temperature sensor
The temperature of the supplied gas is measured by
the INSPIRATORY VALVE TEMPERATURE SENSOR. This sensor
is situated in the gas flow.
The output signal from this sensor is used to
compensate for the gas density variations due to
temperature.
Supply pressure transducer
The pressure of the supplied gas is measured by the
SUPPLY PRESSURE TRANSDUCER.
The output signal from this transducer is amplified. It
is then used to calculate the absolute pressure of the
gas to compensate for gas density variations due to
pressure.
Flow transducer
The gas flows through a net (resistance) which
causes a pressure drop. The pressure is measured on
both sides of this net and the differential pressure
value is then amplified.
4
3
5
6
2
1
SVX9003X

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Description of functions Servo…
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3
Nozzle unit
The plastic NOZZLE UNIT contains a valve diaphragm.
The valve diaphragm, controlled by the INSPIRATORY
SOLENOID, regulates the gas flow through the GAS
MODULE.
The complete plastic nozzle unit must be replaced
during the ”Preventive maintenance”.
After replacement, allow the diaphragm to settle
during approx. 10 minutes before gas pressure is
connected to the GAS MODULE.
Inspiratory solenoid
The gas flow through the GAS MODULE is regulated by
the INSPIRATORY SOLENOID via the NOZZLE UNIT.
The current supplied to the solenoid is regulated so
that the gas module will deliver a gas flow according
to the settings on the User Interface.
Gas module key
The GAS MODULES are provided with a mechanical key
to prevent that the module is mounted in the wrong
slot.
The key consists of a plastic guide mounted under-
neath the module and a corresponding guide
mounted in the patient unit.
Connector muff
The CONNECTOR MUFF connects the GAS MODULE outlets
to the INSPIRATORY PIPE inlet.
Inspiratory pipe
The INSPIRATORY PIPE leads the gas from the CONNECTOR
MUFF to the INSPIRATORY OUTLET.
The INSPIRATORY PIPE comprises:
• Housing and locking lever for the O2CELL with its
bacteria filter.
• Housing for the SAFETY VALVE.
• Connection for measurement of inspiratory
pressure.
The pipe is provided with internal flanges with the
purpose to improve mixing of O2and Air.
O2cell
The O2CELL is mounted in a housing on the INSPIRATORY
PIPE and is protected by a bacteria filter.
Maintenance including exchange of bacteria filter
according to the User´s manual. The bacteria filter
must also be replaced during the ”Preventive
maintenance”.
The O2cell gives an output voltage proportional to the
partial pressure of oxygen inside the Inspiratory pipe.
At constant ambient pressure this output is
proportional to the O2concentration in percent. In
each O2cell, the output signal will stay at a fairly
constant level usually within 10–17 mV in normal air
and at standard barometric pressure during the life
time of the cell. The cell should be replaced when the
output level has started to decrease. In this situation,
repeated calibration (i. e. Pre-use check) of the O2
concentration is required. The life time of the cell is
affected by the O2concentration. With a
concentration (at the cell) in % and expected cell life
time in hours the following applies at 25oC (77oF):
O2Conc. x Expected cell life = 500 000% hours.
The O2cell is automatically calibrated each time a Pre-
use check is performed (if O2is connected to the
ventilator).
An ID PROM is integrated into each O2cell. Its ID
information and remaining lifetime can be read by the
Servo…System.
Temperature sensor
A TEMPERATURE SENSOR is integrated into the connector
on top of the O2CELL. This sensor measures the
temperature inside the INSPIRATORY SECTION.
The output signal, corresponding to the temperature
in the INSPIRATORY SECTION, is used for regulation of the
INTERNAL FAN.
Inspiratory pressure tube
The INSPIRATORY PRESSURE TUBE connects the INSPIRATORY
PIPE with the INSPIRATORY PRESSURE TRANSDUCER.
A bacteria filter protects the pressure transducer on
PC 1781 PRESSURE TRANSDUCER from contamination.
Maintenance including exchange of bacteria filter
according to User´s manual. The bacteria filter must
also be replaced during the ”Preventive
maintenance”.