Frontline Sirius Repair and Calibration Manual Issue 2 Oct 2005

Frontline Sirius®

Important Read this manual before operating or servicing the machine. Read the vaporizer manual before operating the machine. For all users and Service Personnel, refer to the User Manual before operating the machine.

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Repair and Calibration Maintenance Manual

Frontline Sirius®

Introduction

Table of Contents Product Improvement.................................................................................................................. 7 Responsibilities of the Manufacturer....................................................................................... 7 Disclaimer....................................................................................................................................... 7 Note to Service Personnel........................................................................................................... 8 Copyright......................................................................................................................................... 8 CE Marking...................................................................................................................................... 8 Trademarks and Acknowledgements....................................................................................... 9 Symbols and Abbreviations........................................................................................................ 10 Hazard Notices ............................................................................................................................. 11 Warnings ......................................................................................................................................... 12 Electrostatic Sensitive Devices (ESD) Warnings and Cautions ........................................... 13 Cautions........................................................................................................................................... 13 1. Technical Description............................................................................................................. 17 1.1 Mode Descriptions for the Sirius Ventilators..............................................................................................23 1.1.1 PEEP ....................................................................................................................................................................23 1.1.2 Control Panel.................................................................................................................................................23 1.1.3 Control System .............................................................................................................................................23 1.1.4 Volume Control Ventilation (CMV) ...................................................................................................24 1.1.5 8500s Ventilator Fresh Gas and Compliance Compensation ............................................24 1.1.6 Fresh Gas..........................................................................................................................................................24 1.1.7 Compliance.....................................................................................................................................................24 1.1.8 Pressure Control Ventilator (PCV) .....................................................................................................26 1.1.9 Inspiratory Pause .........................................................................................................................................26 1.1.10 Sigh ......................................................................................................................................................................26 1.1.11 Spontaneous or PSV..................................................................................................................................26 1.1.12 Pressure Support .........................................................................................................................................26 1.1.13 SIMV ....................................................................................................................................................................27 1.2 Matrix of Modes, Facilities and Alarms..........................................................................................................29 1.2.1 CMV Defaults at Start up ........................................................................................................................29 1.2.2 Spontaneous with Pressure Support Defaults at Start up...................................................30 1.2.3 Pressure Control Ventilation Defaults at Start up ....................................................................30 1.2.4 6700 8700 8500MKII Principles of Operation ............................................................................34 2. Removal / Replacement Instructions................................................................................. 35 2.1 Removal of Outer Cases........................................................................................................................................37 2.2 Mechanical Hypoxic Guard Block .....................................................................................................................45 2.2.1 Introduction....................................................................................................................................................45 2.2.2 Calibration of Hypoxic Guard System.............................................................................................46 2.2.3 Calibration Procedure ...............................................................................................................................46 2.3 Setting Oxygen Basal Flow....................................................................................................................................49 2.4 Nitrous Oxide and Air Flow Valve Leak Test ..............................................................................................54 2.5 Removal of Flow Tubes..........................................................................................................................................55 2.6 Mechanical Hypoxic Guard Regulators, Adjustment and Output Check ...................................57 2.6.1 Hypoxic Regulator Replacement.........................................................................................................59 2.7 Backbar Test..................................................................................................................................................................61 Repair and Calibration Maintenance Manual

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Frontline Sirius® 2.7.1 Backbar Valve Test......................................................................................................................................61 2.7.2 Backbar Valve Replacement ..................................................................................................................63 2.8 Common Gas Outlet (CGO) Removal / Replacement.........................................................................65 2.9 Alarm Block Removal / Replacement.............................................................................................................66 2.10 Oxygen Flush of Common Gas Outlet Safety Valve Adjustment..................................................67 2.10.1 Oxygen Flush Adjustment.......................................................................................................................68 2.11 Flow Meter Removal...............................................................................................................................................69 2.12 On/Off Switch Removal........................................................................................................................................71 2.13 Absorber Interface Manifold Assembly ........................................................................................................73 2.13.1 Absorber ..........................................................................................................................................................74 2.13.2 Bellows Interface Gasket .........................................................................................................................77 2.13.3 Absorber Alignment ...................................................................................................................................78 2.13.4 Standby / Run ...............................................................................................................................................78 2.13.5 Absorber Docking ........................................................................................................................................79 2.14 Writing Surface + Drawer Removal................................................................................................................80 2.15 Drawer Catch Removal / Replacement .......................................................................................................83 2.16 Suction Controller Removal / Replacement..............................................................................................85 2.17 Full System Test .........................................................................................................................................................87 2.17.1 Leak Test ...........................................................................................................................................................87 2.17.2 On/Off Switch and Warning System Checks...............................................................................88 2.17.3 Mechanical Hypoxic Guard Test..........................................................................................................89 2.17.4 Oxygen Flush Tap Test..............................................................................................................................89 2.17.5 Auxiliary Outlet Test ...................................................................................................................................89 2.17.6 Vaporizer Test ................................................................................................................................................89 2.17.7 Ventilator Test ................................................................................................................................................89 2.18 Inspiratory Block Assembly .................................................................................................................................91 3. Ventilator Calibration Details .............................................................................................97 3.1 BleaseTerm.....................................................................................................................................................................99 3.1.1 Controls ..........................................................................................................................................................100 3.1.2 Flow Control Calibration.......................................................................................................................103 3.1.3 Sensor Calibration ....................................................................................................................................108 3.1.4 Zero Offset Correction ...........................................................................................................................108 3.1.5 Pressure Sensor Gain ..............................................................................................................................113 3.1.6 Delivered Volume Calibration ............................................................................................................115 3.1.7 Fresh Gas Flow Sensor Gain ...............................................................................................................117 3.1.8 Hardware Pressure Overload Backup ...........................................................................................118 3.1.9 6700 Additional Steps............................................................................................................................119 3.1.10 On Screen Calibration.............................................................................................................................120 3.1.11 Fresh Gas Calibration ..............................................................................................................................120 3.1.12 Monitored Inspired and Expired Volume (vte + vti).............................................................120 3.1.13 6700 Only ......................................................................................................................................................121 3.1.14 Calibration Value Limits .........................................................................................................................122 3.1.15 SPC Configuration for 6700 Oxygen..............................................................................................123 3.1.16 SPC Configuration for 8700 Oxygen..............................................................................................123 4. Diagrams................................................................................................................................ 125

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Repair and Calibration Maintenance Manual

Frontline Sirius®

List of Figures Figure 1 Figure 2 Figure 3 Figure 3a Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 Figure 15 Figure 16 Figure 17 Figure 18 Figure 19 Figure 20 Figure 21 Figure 22 Figure 23 Figure 24 Figure 25 Figure 26 Figure 27 Figure 28 Figure 29 Figure 30 Figure 31 Figure 32 Figure 33 Figure 34 Figure 35 Figure 36 Figure 37 Figure 38 Figure 39 Figure 40 Figure 41 Figure 42 Figure 43 Figure 44 Figure 45

Frontline Sirius 3000 ..............................................................................................18 Frontline Sirius 2000 + 1000 ................................................................................20 Inspired gas Flow Diagram...................................................................................31 Absorber Pneumatic Schematic...........................................................................32 Sirius 3000 Pneumatic Schematic.......................................................................33 Removal of Top Surface ........................................................................................37 Removal of Front Moulding..................................................................................40 Front of Machine .....................................................................................................40 Close up of front of Machine ...............................................................................41 Rear of Machine ......................................................................................................42 Location of Rear Screws ........................................................................................43 Part Rear Panel Removed .....................................................................................43 Complete Rear Panel Removed...........................................................................44 Assembled Hypoxic Guard Unit...........................................................................50 Exploded View of Hypoxic Guard Components...............................................51 Flow Block showing tube filters and tube lower inserts...............................52 View of Assembled Hypoxic Guard from Below..............................................53 Flow Tube Removal ................................................................................................55 Test Points ................................................................................................................57 Regulator Adjustment ............................................................................................58 Regulator Nut ...........................................................................................................59 Regulator Flow Direction ......................................................................................60 Back bar ....................................................................................................................63 Back bar Valve .........................................................................................................64 CGO Block .................................................................................................................65 Alarm Block Removal .............................................................................................66 CGO Adjustment ......................................................................................................67 Valve and Adjuster Disc Removed ......................................................................68 Flow Meter Removal...............................................................................................69 On/Off Switch Removal ........................................................................................71 Absorber Interface Manifold Assembly .............................................................73 Absorber....................................................................................................................74 Bellows Interface Gasket.......................................................................................77 P-Clip..........................................................................................................................78 Writing Surface + Drawer Removal ....................................................................80 Drawer Catch Removal / Replacement..............................................................83 Suction Controller Removal / Replacement .....................................................85 Suction Controller in Position..............................................................................86 Ventilator Case Top ................................................................................................91 Inside Ventilator......................................................................................................92 Blease Term Start Screen ......................................................................................100 BleaseTerm Sensor Calibration ...........................................................................101 BleaseTerm Ventilator Options............................................................................101 BleaseTerm Defaults/Save Options....................................................................102 Flow Control Calibration .......................................................................................103 Sensor Calibration ..................................................................................................108

Repair and Calibration Maintenance Manual

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Frontline Sirius® Figure 46 Figure 47 Figure 48 Figure 49 Figure 50 Figure 51 Figure 52 Figure 53 Figure 54 Figure 55 Figure 56 Figure 57 Figure 58 Figure 59 Figure 60 Figure 61 Figure 62 Figure 63 Figure 64

6

Pressure Sensor Gain ............................................................................................ 113 Delivered Volume Calibration............................................................................. 115 Fresh Gas Flow Sensor Gain ................................................................................ 117 Hardware Pressure Overload Backup ............................................................... 118 BAV Power Supply.................................................................................................. 126 BAV Controller Type 2 PWM ................................................................................ 127 BAV Controller Type 2 Analogue ........................................................................ 128 BAV Controller Type 2 Connect........................................................................... 129 8700 Electrical Interconnection .......................................................................... 130 BAV Controller Type 2 CPU .................................................................................. 131 6700/8700 Pneumatic System Diagram........................................................... 132 Blease Display Interface ....................................................................................... 133 Blease Display Interface ....................................................................................... 134 BAV Controller Type 2 Alarms............................................................................. 135 Blease Display Interface ....................................................................................... 136 Blease Display Interface ....................................................................................... 137 Blease Display Interface ....................................................................................... 138 BAV Controller Type 2 I/O Circuits..................................................................... 139 BAV Controller Type 2 Memory .......................................................................... 140

Repair and Calibration Maintenance Manual

Frontline Sirius®

Product Improvement Blease Medical Equipment Limited has a policy of continued product improvement and therefore reserves the right to make changes which may affect the information contained in the manual without giving prior notice.

Responsibilities of the Manufacturer The manufacturer accepts responsibility for the effects on safety, reliability and performance of the equipment only if: • • •

assembly operations, extensions, adjustments, modifications and repairs are carried out by persons with written authorisation from the manufacturer; the equipment is used in accordance with the instructions for use; the electrical installation of the relevant room complies with the ‘Regulations for the Electrical Equipment of Buildings’. NB If during the warranty period the equipment is serviced by an unauthorised party, the warranty will be void.

Disclaimer Opening of the control unit by unauthorised personnel automatically voids all warranties and specifications. The prevention of tampering is solely the user's responsibility; the manufacturer assumes no liability for any malfunction or failure of the ventilator if the control unit is opened. The instructions in this manual assume that the engineer is familiar with and has had training in the servicing and care of anaesthetic equipment and is able to use pressure gauges, flowmeters and other laboratory equipment. Blease accept no responsibility or liability for any patient injury or adverse circumstances which may arise from unauthorised maintenance of Blease Frontline Sirius Machines.

Repair and Calibration Maintenance Manual

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Frontline Sirius®

Note to Service Personnel The Frontline Sirius® and integrated equipment must only be serviced by Qualified Service personnel. The contents of this manual are not binding. If any significant difference is found between the product and this manual please contact Blease Medical Equipment Limited for further information. To ensure correct functioning, the equipment must be serviced at regular intervals. Blease Medical Equipment Limited recommends that the machine should be serviced at intervals not exceeding three months. Qualified Service Personnel and genuine spare parts should be used for all servicing and repairs. Blease Medical Equipment Limited will not otherwise assume responsibility for the materials used, the work performed or any possible consequences of the same. In communication with Blease Medical Equipment Limited, quote the model and serial number of the equipment, with the approximate date of purchase. If the equipment is being returned for repair, indicate the nature of the fault or the work you require to be carried out. Contact: Blease Medical Equipment Limited Beech House • Chiltern Court • Asheridge Road • Chesham • Buckinghamshire HP5 2PX • England Tel: +44 (0)1494 784422 Fax: +44 (0)1494 791497 e-mail (enquiries): [email protected] e-mail (technical): [email protected] www.blease.com

Copyright ©2005, Blease Medical Equipment Limited. E & OE. All rights reserved. The information contained in this publication may not be used for any other purpose than that for which it was originally supplied. This publication may not be reproduced in part or in whole without the written consent of Blease Medical Equipment Limited.

CE Marking The product is labelled with the CE mark. 8

0120 Repair and Calibration Maintenance Manual

Frontline Sirius®

Trademarks and Acknowledgements The following symbols and acknowledgments may appear in Blease product manuals:

is the trademark of Abbott Laboratories.

Da-LitesTM is a trademark of Blease Medical Equipment Limited UK. Datum® is a registered trademark of Blease Medical Equipment Limited UK. Dowty is a trademark of Dowty Seals Limited. Draeger is a trademark of Draegerwerk AG Germany. Dzus is a trademark of Dzus Fasteners Limited. Fomblin® is a registered trademark of Rocol Limited. Frontline Sirius 1000® is a registered trademark of Blease Medical Equipment Limited. Frontline Sirius 2000® is a registered trademark of Blease Medical Equipment Limited. Frontline Sirius 3000® is a registered trademark of Blease Medical Equipment Limited. Legrand® is registered trademark of Legrand Electric Limited. Loctite® is a registered trademark of Loctite Corporation USA. Megger is a trademark of AVO Megger Instruments Ltd. Plug-in® is a registered trademark of Draegerwerk DAG Germany. Quik-Fil® is a trademark of Abbott Laboratories. Rigel is a trademark of Seaward Electronics Ltd. Scotchbrite® is a registered trademark of 3M. SELECTATEC® is a registered trademark of Ohmeda/BOC UK Ltd. Snoop® is a registered trademark of the Nupro® Company Ohio USA. Trak Wheel® is a registered trademark of Blease Medical Equipment Ltd.

Repair and Calibration Maintenance Manual

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Frontline Sirius®

Symbols and Abbreviations bpm BPM

Breaths per minute

cmH2 O

Gauge pressure expressed in centimetres of water

CPAP

Continuous positive airway pressure

PEEP

Positive end expiratory pressure

I:E Ratio

A ratio of inspiratory to expiratory time IEC symbol to consult the instructions for use IEC symbol denoting type of equipment (B) WARNING: There is danger of personal injury to the user or patient Further relevant or helpful information

Power off

Power on

Dangerous voltage

l/m

lpm

Litres per minute

ml

Millilitres

O2

Oxygen

psi

Pounds per square inch

psig

Pounds per square inch gauge

l

Litres IEC symbol for alternating current Confers approval under theEuropean Medical Device Directive E of C

End of Case This symbol indicates that the waste of electrical and electronic equipment must not be disposed as unsorted municipal waste and must be collected separately. Please contact an authorized representative of the manufacturer for information concerning the decommissioning of your equipment.

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Repair and Calibration Maintenance Manual

Frontline Sirius®

Hazard Notices This handbook contains important hazard information. You must read this hazard information before using the Frontline Sirius®.

Warning Notices Warning notices denote a potential hazard to the health and safety of users and/or patients. These notices clearly state the nature of the respective hazard and the means by which it can be avoided. Warning notices appear in full in the preliminary pages and are repeated at their points of application in the manual.

Caution Notices Cautionary notices denote a potential hazard to the physical integrity of equipment/software but NOT a danger to personnel. These notices clearly state the nature of the hazard and the means by which it can be avoided. Cautionary notices appear in full in the preliminary pages and are repeated at their points of application in the manual.

Relevant or helpful Information

Repair and Calibration Maintenance Manual

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Frontline Sirius®

Warnings The following statements are made to comply with the requirements of IEC 60601-1. 1.

This equipment must only be connected to gas pipeline supply lines that are fitted with pressure relief valves that limit the supply pressure to less than 7 bar.

2.

The functioning of this machine may be adversely affected by the operation of equipment such as high frequency surgical (diathermy) equipment, defibrillators or shortwave therapy equipment in the vicinity. Increasing the distance from such equipment will minimise any possible interference.

3.

Prior to connecting the machine to a patient carry out the pre-use check to verify correct alarm operation. To verify the O2 alarm, set the flowmeters to give a concentration of 50% oxygen. Using the controls on the oxygen monitor panel, set the low oxygen level to 60% and verify the oxygen low alarm operates. Set the high oxygen alarm level to 40% and verify that the oxygen high alarm operates.

4.

The oxygen flow can only be reduced to zero by turning the ON/OFF switch to the OFF position. Excessive force on the oxygen control knob may damage the hypoxic guard.

5.

To avoid explosion hazards, flammable anaesthetic agents such as ether and cyclopropane must not be used in these machines. Only anaesthetic agents which comply with the requirements on non-flammable anaesthetic agents in IEC 60601-2-13 ‘Specification for Anaesthetic Machines’, are suitable for use in these machines.

6.

As these machines are not suitable for use with flammable anaesthetic agents such as ether and cyclopropane the use of antistatic breathing tubes and face masks is not necessary. The use of antistatic or electrically conductive breathing tubes when utilising high frequency surgery equipment may cause burns and is therefore not recommended in any application that involves such apparatus.

7.

The equipment must be periodically checked and maintained to ensure proper operation.

8.

Performance of the equipment may be affected at temperatures below 10oC (50oF) and above 40oC (104oF).

9.

The performance of the anaesthetic machines and vaporizers may be degraded if the two are mismatched. Refer to the vaporizer manufacturer’s instruction manual before use.

10. If the integrated oxygen analyser is not fitted, an oxygen analyser complying with ISO 7767 shall be used when the anaesthetic machine is in use. 11. The units use semiconductor devices which are susceptible to damage by overloading, reversed polarity, electrostatic discharge and excessive heat or radiation. Avoid hazards such as reversal of batteries, prolonged soldering, strong RF fields or other forms of radiation, use of insulation testers or accidentally applied short circuits. Even the leakage current from an unearthed soldering iron may cause trouble.

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Repair and Calibration Maintenance Manual

Frontline Sirius®

Electrostatic Sensitive Devices (ESD)

Warnings and Cautions All ESD must be stored in approved conductive packaging, tubes, shipping bags, foam or tote bins. All persons handling ESD must be properly grounded via a 1MW resistive grounded wrist strap. Cover all ESD bench tops with grounded conductive mats and connect all work surfaces and equipment to earth ground. Transport all assemblies containing ESD in a conductive bag or container. DO NOT use cellophane adhesive tape to wrap DIP (dual in-line package) tubes together. DO NOT handle ESD by their pins or mix them with other routine electronic parts. Never place ESD on ungrounded surfaces or leave them unattended in an open area. Avoid cellophane wrappers, synthetic (non-conductive) carpeting, warm or cool air blasts, Styrofoam coffee cups, etc when working with ESD. Use only properly designed heat lamps, heat chambers and/or ‘antistatic’ quick-chill sprays during troubleshooting or stress testing procedures. NB In particular electronic assemblies in the Frontline Sirius® range of machines are easily damaged by ESD and require special handling.

Cautions Anaesthetic Machines Do not leave gas cylinder valves open if the pipeline supply is in use and the system master switch is turned ON. Pressures from both supplies may become equal and, if simultaneously used, cylinder supplies could be depleted, leaving an insufficient reserve supply in case of pipeline failure. The hypoxic guard control system only ensures that oxygen-nitrous mixtures will have a minimum oxygen concentration. HYPOXIC MIXTURES MAY BE DELIVERED IF GASES OTHER THAN OXYGEN, NITROUS OXIDE OR AIR ARE USED, OR WHEN OPERATING AT LOW OXYGEN FLOW RATES. When using carbon dioxide, as an additional gas, make sure the proportions of all gases are carefully adjusted in accordance with accepted clinical practice. Gas mixtures within the breathing system must be monitored when using these gases. Repair and Calibration Maintenance Manual

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Frontline Sirius® Leaking gases and vapours (downstream of the flow control valves and Oxygen Flush valve) may deprive the patient of metabolic gases and anaesthetic agent may pollute the atmosphere. Tests that detect leaks must be performed frequently. If detected, leakage must be reduced to an acceptable level. Do not use the anaesthesia system if the hypoxic guard control system does not operate within permitted ranges. Using an incorrectly operating control system may result in incorrect gas mixtures and injury to the patient. When occluding the breathing system for test purposes, do not use any object small enough to slip completely into the system. Objects in the breathing system can interrupt or disrupt the delivery of breathing system gases, possibly resulting in injury to the patient. Before using the breathing system on a patient, always check the breathing system components for foreign objects. Do not place materials weighing more than 50kg on the bottom shelf, or more than 25kg on the upper monitor shelf. Overloading may cause damage to the shelves or cause instability. Secure any equipment placed on the shelves. To avoid stripping threads, do not use tools on the yoke gate T screws. Use only one cylinder gasket per yoke. Using more than one gasket could cause cylinder gas leakage.

Ventilator The volume sensor must be correctly installed at either the distal location in the patient system’s expiratory limb or the proximal end of the Y connector. If the sensor is installed incorrectly, volume data will be inaccurate and associated alarms, including the low minute volume alarm will not function properly. Position the volume sensor’s cable with care. If the cable is pinched or cut, the ventilator’s volume monitoring may not function correctly. Do not connect the ventilator or absorber exhaust directly to a vacuum source. The vacuum may remove required gases from the breathing system. (Only applies to Frontline Sirius 1000® and 2000®). Ventilator inoperative messages indicate that a problem exists in the ventilator. Do not attempt to use the ventilator while a ventilator message is displayed. Do not attempt to use the ventilator if the alarm mute button will not silence alarms. WARNING: If an alarm condition cannot be resolved, do not continue to use the system. Sterilise the bellows assembly periodically to minimise the risk of cross infecting patients. Use a sterilization schedule that complies with your institution’s infection control and risk management policy. Only use Blease approved sterilization methods. If any foreign materials or liquids are trapped in the driving gas circuit, or the pop off valve or the bellows base they could impair the valve’s operation. Do not use the bellows assembly if 14

Repair and Calibration Maintenance Manual

Frontline Sirius® you suspect that materials are trapped. Have the assembly repaired by trained service personnel. Perform the Pre-Use Check procedures after cleaning and sterilizing the bellows. Always perform the Pre-Use Check procedures for volume sensing functions after cleaning or replacing the volume sensor.

Vaporizer Do not use any vaporizer that is visibly misaligned on the manifold or that, when it is locked, can be lifted off the manifold. Incorrect mounting may result in incorrect delivery of gases. A vaporizer is calibrated and labelled for one agent only. Do not fill with anything other than the designated agent. If a vaporizer is filled with the wrong agent, draining will not eliminate the agent, because the wick will have absorbed some of the agent. The wick must be thoroughly cleaned and dried by trained service personnel. The vaporizers must be completely upright for the sight glass to properly indicate agent levels. Never oil or grease any oxygen equipment unless the lubricant used is made and approved for this type of service. In general, oils and greases oxidise readily, and - in the presence of oxygen will burn violently. Fomblin is the recommended oxygen service lubricant (stock number ST7014). After performing any maintenance or repair procedure, always verify proper operation of the system before returning to use. Use cleaning solution sparingly. Do not saturate system components. Excessive solution can damage internal devices. Following ethylene oxide sterilization, quarantine the equipment in a well ventilated area to allow dissipation of absorbed ethylene oxide gas. In some cases, aeration periods of seven days or more may be required. Aeration time can be decreased when special aeration devices are used. Follow the sterilizer manufacturer’s recommendations for aeration periods required.

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Frontline Sirius®

Notes

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Repair and Calibration Maintenance Manual

1. Technical Description

Frontline Sirius®

1. Technical Description

Repair and Calibration Maintenance Manual

17

1. Technical Description

Frontline Sirius®

A

B

C

D T E

S R

F

Q G P H O

I

N

M

J

L

K

Figure 1 Frontline Sirius® 3000 18

Repair and Calibration Maintenance Manual

Frontline Sirius®

1. Technical Description

Key to Figure 1 A

Monitor shelf

B

Ventilator

C

Independent O2 Flowmeter (only on the 3000 model)

D

Vaporizer

E

Cylinder/Pipeline Gauges

F

Pneumatic Unit - (behind gauge panel)

G

Handle

H

Oxygen Flush

I

Common Gas Outlet

J

Writing Table

K

Drawer

L

Frame

M

Suction Receiver Jar

N

Anaesthetic Gas Scavenging System (AGSS)

O

Absorber

P

Bellows

Q

Suction Controller

R

Main On/Off or Off, N2O/Air Interlock Switch

S

Flow Control Valves with Hypoxic Guard

T

Flowblock Assembly

Repair and Calibration Maintenance Manual

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1. Technical Description

Frontline Sirius® A

L

B

J

C

J

D

I

E

F

G H

Fig 2

Sirius 2000 & Sirius 1000 M

N T S R

Q

20

O

P

Repair and Calibration Maintenance Manual

Frontline Sirius®

1. Technical Description

Key to Figure 2 Sirius 2000 A

Monitor shelf

B

Ventilator

C

Vaporizer

D

Cylinder/Pipeline Gauges

E

Pneumatic Unit - (behind gauge panel)

F

Oxygen Flush

G

Frame

H

Absorber

I

Bellows

J

Main On/Off or Off, N2O/Air Interlock Switch

K

Flow Control Valves with Hypoxic Guard

L

Flowblock Assembly

Sirius 1000 M

Ventilator

N

Vaporizer

O

Cylinder/Pipeline Gauges

P

Pneumatic Unit

Q

Oxygen Flush

R

Main On/Off or Off, N2O/Air Interlock Switch

S

Flow Control Valves with Hypoxic Guard

T

Flowblock Assembly

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1. Technical Description

Frontline Sirius®

Notes

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Repair and Calibration Maintenance Manual

Frontline Sirius®

1.1

1. Technical Description

Mode Descriptions for the Sirius Ventilators

1.1.1 PEEP 1.1.2 Control Panel The control panel has a permanent display of measured PEEP and a button to actuate the setting of the desired value. The display box will have the heading “PEEP” and show the “SET” value. The default is that PEEP will be at the minimum setting i.e the residual that is < 2cmH2O caused by the bellows assembly. In this default condition or if the Set value is subsequently set below 3 cmH2O the set value display will show as “OFF”. The method of control is that the user will rotate the Trak Wheel until the desired display is highlighted, press the Trak Wheel and then increase the set value by rotating the Trak Wheel until the desired value is reached, this is then accepted by a further press of the Trak Wheel. The range of set values will be 3 to 20 cmH2O. An alarm will be implemented to indicate to the user that the set value has not been maintained. The alarm will activate at ± 50% of the set value. To activate a set value that has been chosen, be sure to press the Trak Wheel to confirm. If you fail to confirm the change will not be saved and the previous value will rest (reappear) after a time out period. This applies to all Trak Wheel controls. The implication of PEEP on other alarms is that the Pressure cycle alarms will be PEEP referenced, the pressure Limit will be absolute. i.e. Referenced to atmosphere.

1.1.3 Control System For the control system to effect PEEP the following will need to be activated :A pulse width modulator will control the power to the coil of a PEEP valve. This valve is a voice coil actuator working as a variable spring applying force to a disc that impinges on a seat. The implication being that the valve is closed until the gas pressure exceeds the actuator force. The control processor will monitor the PEEP value and modify the PWM setting to maintain the desired value.

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1. Technical Description

Frontline Sirius®

1.1.4 Volume Control Ventilation (CMV) Volume Control Ventilation is a mechanical mode that delivers a tidal volume set by the user into the patient tubing. This delivered volume is to be independent of the compression losses in the absorber, bellows and associated tubing. It will also be independent of any small leaks that may be present. Fresh gas flowing into the breathing system will not cause a permanent change in the delivered volume. If a change in fresh gas flow rate occurs during ventilation the ventilator will re-adjust the delivered tidal volume to be correct within the next 4 breaths.

1.1.5 8700 Ventilator Fresh Gas and Compliance Compensation 1.1.6 Fresh gas Fresh gas flow adds to the delivered Tidal Volume during the inspiratory period. To compensate for this, a reduction in the delivered volume needs to be made. This reduction is :FG Flow rate ml / M x Insp Time (sec) 60 Take FG = 5 LPM

TV 600 ml

10 BPM

I:E 1:2.0

5000 x 2 seconds = 166 ml 60 New Effective TV is now 600 - 166 = 434 ml

1.1.7 Compliance The effect of the gas being compressed in the dead space within the breathing system is to reduce the Volume (TV) that is delivered to the patient. In an ideal ventilator the Set TV would be the volume of gas that is delivered to the patients lungs. This can only be partly achieved because the anatomy of the patient is unknown, what can be done is the set TV can be made to be accurately delivered from the catheter mount. Thus reducing set TV errors to a minimum.

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Repair and Calibration Maintenance Manual

1. Technical Description

Frontline Sirius®

To calculate the effect of the Breathing System compliance on the delivered TV it is necessary top measure what the capacity or compliance of the system is (Cs). This can only be done by some form of pre-use check procedure. In essence it is necessary to have the ability to first of all select “Compliance Compensation” from a menu. It is then necessary to lead the user through the process of measuring the dead space within the particular breathing system for that period of use. It is obvious that should the system be re-configured the test will need to be repeated. A possible process is to allow the ventilator to prompt the user to : 1. Reduce the FG flow to minimum (but Allow for it as above). 2. Occlude the catheter mount. This can be a 15 mm male taper on the gas machine. 3. The ventilator then delivers a breath to pressurize the system to 10cmH2O. 4. The ventilator records the volume required to achieve this pressure and verifies that a leak is not present. The dead space is now calculated as follows : Volume in ___ml__ = Dead space compliance C s Pressure This figure is stored until the ventilator is switched off or a re-test is asked for by the user. The ventilator is then set to use on a patient and when the ventilation is stable measure the total compliance of system and patient Ct. An adjustment can then be made to the TV that will be increased to compensate for the lost volume due to compression within the breathing system. : Increase in TV -= Set TV

x

1+

Cs Ct — Cs

= new TV

E.g System test measurement using 200 ml gave 25 cmH2O pressure rise. 80 ml 10cmH2O

= Cs

=

8

Running the ventilator on a patient with a set 500 ml TV gave 20 cmH2O peak pressure. 500 ml 20 cmH2O

= Ct

=

25

So to calculate the TV increase: 500

x

1 +

8 ________ 25 - 8

Repair and Calibration Maintenance Manual

=

735 ml

25

1. Technical Description

Frontline Sirius®

So 735 ml is the actual ventilator output into the breathing circuit to give 500 ml at the catheter mount. This figure would have to be recalculated in the light of any fresh gas flow change as above but would just be a variation on the 735 ml figure.

1.1.8

Pressure Control Ventilator (PCV)

Pressure control ventilation is time cycled mode where the ventilator strives to produce the user set inspiration pressure for the inspiratory period. To accomplish this goal, the inspiratory flow rate and pressure are set by the user. To do this, the control that is used for the Set TV function will be reassigned as “I Flow” and calibrated in LPM. The pressure Limit control becomes the “Set Pressure” control. This allows the user to define the delivered wave form. The default pressure will be 30 cm H2O in both Adult and Paediatric modes.

1.1.9

Inspiratory Pause

A function that is “Inspiratory Pause” is to be implemented. This option will be available in volume and PCV mode such that a pause of 25% of the inspiratory time is used as a Plateau before starting the expiratory phase. This means the expiratory time is reduced by the plateau time. If at all possible the pause or plateau time should be made variable from 5 to 60 %. The x % should be displayed on the second row up of the display.

1.1.10

Sigh

Sigh is a function that can be selected in volume or Pressure ventilation the effect is that every 50 breaths the delivered breath is increased by 15%. The selection of this function will be displayed as an extension to the main mode display under the bar graph.

1.1.11

Spontaneous or ASB

Spontaneous is a mode that is equivalent to the machine being in standby will all monitoring enabled. This allows a patient to breath at their own rate and volume with the ventilator being able to display the monitored parameters and actuate alarms. At this level the Breathing rate would be a monitored parameter, it should follow the same pattern as other features in that it will display the monitored value in large characters and show Assisted Spontaneous Breathing ’ASB’ as the mode.

1.1.12

Pressure Support

When a patient is taking a “Spontaneous Breath” from an anaesthetic system the work of breathing is higher than normal. To overcome this it is desirable for the ventilator to be able to assist the spontaneous breath. The assistance is provided by the ventilator sensing the negative pressure cause by the “Patient Attempt” to breath and initiating flow from the ventilator. This flow is continued to the point where the breathing circuit pressure has reached a set value. i.e. Pressure Support. To implement this action the user needs to be able to set first the trigger threshold in the range –1 to –10 cmH2O and secondly the Support Pressure 0 to 30 cmH2O both referenced to the PEEP level.

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1. Technical Description

It will also be necessary to define a inspiratory time in which the pressure support is delivered. In this case the breathing rate and tidal volume are not relevant. The inspiratory flow rate will be a fixed value of 40 LPM in Adult and 30 LPM in Paediatric. The detection of a “Patient Attempt” will be carried out by the control system to aid the speed of support. A patient attempt will be indicated on screen by the negative excursion of the pressure wave form being green rather than blue for the positive phase.

1.1.13

SIMV

This mode is Synchronised Intermittent Mandatory Ventilation. This is an extension of the spontaneous mode in so far as the patient can take breaths on demand with pressure support but some mandatory breaths are included. To achieve this it is necessary to set a tidal volume, a breathing rate and all of the features described above for the pressure support. To simplify things a little the inspiratory flow rate an be assumed from the TV / inspiratory Time set values. The patient attempt or trigger signal will be used to synchronise the mandatory breaths to the patients breathing pattern and initiate the pressure supported spontaneous breaths. Thus allowing the patient to establish the breathing rate. In this way a patient could be breathing at say 12 BPM with the settings such that 4 breaths of say 500 ml are mandatory and 8 breaths are taken spontaneously with pressure support of up to 30 cmH2O above the PEEP level. The ventilator will monitor all of the breaths, display the parameters TV /BPM / I:E and indicate the patient attempt by showing negative excursions of the graph in RED. The set breathing rate and measured rate will be displayed, the Set Inspiratory time and I:E ratio will be displayed in the appropriate window. A means if preventing hyperventilation will be implemented such that any change in breathing rate is only allowed to take place slowly. The method of inflating the patient’s lungs and the operation of the valves and the gas flows in the SIMV mode are the same as for the CMV mode. The main difference between this mode and CMV is that a facility is provided for synchronising the mechanical breaths given by the ventilator to the patient’s own respiratory efforts (spontaneous breaths). If the patient fails to make any effort, then SIMV will default to ventilation functionally identical to CMV at the set SIMV rate. The routine within the ventilator that detects the Patient Trigger is used to detect the instant a patient starts to inhale and is thus ready for a synchronised breath to be given by the ventilator. Whether a breath is spontaneous or mandatory depends on where it occurs in the SIMV cycle.

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1. Technical Description

Frontline Sirius®

This can be explained as follows :1. The frequency control sets up an internal clock tick in the ventilator. The time between clock ticks is the Set breathing period and is equal to a time in seconds of 60/frequency in BPM. I.e. 4BPM = 1 tick every 15 seconds. With no patient triggers detected, the ventilator will deliver a mechanical breath at the start of each respiratory period on the clock tick. 2. Preceding each clock tick is a time window in which the ventilator will be looking for a patient trigger. If a trigger occurs within the window the patient will be given a synchronised mechanical breath. If it occurs outside the window it will be a spontaneous or Pressure Supported spontaneous breath depending on the ventilator setting. In practical use of the SIMV mode, the ventilator should first be set at an adequate RATE, TIDAL VOLUME, I:E RATIO, PEEP and PRESSURE LIMIT for controlled ventilation, say 600 ml, 12 BPM and 1.5 secs for an adult patient. When patient trigger signals are being displayed regularly the mandatory rate can be reduced and the total breathing rate will be controlled by the patient. If this rate is inadequate and the total breathing rate will be controlled by the patient. If this rate is inadequate the low MV or Rate alarm will be activated.

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1. Technical Description

Frontline Sirius®

1.2

Matrix of Modes, Facilities and Alarms

Mode

Sigh

CMV

Pause

??

Press Supp PEEP

??

MV Alm Rate Alm

??

??

Press Alm ??

Spont

??

??

??

??

??

??

SIMV

??

??

??

??

??

??

??

??

??

PCV

??

??

1.2.1 CMV Defaults at start up Vol

Rate

Insp TIME

Press Limit

Vol Alm

Press Alm

Lo / Hi

Lo / Hi

Adult

500 ml

12

1.5

50

4 / 10

4 / 55

Paed

150 ml

20

1.5

40

1/6

4 / 45

I:E

Press Limit

Vol Alm

Press Alm

Lo / Hi

Lo / Hi

SIMV Defaults at start up Vol

Rate

Adult

500 ml

12

1:2.0

50

4 / 10

4 / 55

Paed

150 ml

20

1:2.0

40

1/6

4 / 45

Spontaneous Defaults at start up Support Pressure

Rate Alm Vol Alm

Press Alm

Lo / Hi

Lo / Hi

Lo / Hi

Adult

10

5 / 25

4 / 10

4 / 50

Paed

10

10 / 35

1/6

4 / 40

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1. Technical Description

Frontline Sirius®

1.2.2 Spontaneous with Pressure Support Defaults at start up Insp Flow

Insp TIME

Support Pressure

Press Rate Alm Vol Alm Limit Lo / Hi Lo / Hi

Press Alm

Adult

30L

1.5

10

50

5 / 25

4 / 10

4 / 55

Paed

20L

1.5

10

40

10 / 35

1/6

4 / 45

Lo / Hi

1.2.3 Pressure Control Ventilation Defaults at start up Insp Flow

Ventilation Pressure

Rate

Press Alm

Adult

30L

30

12

4 / 50

Paed

20L

20

20

4 / 40

Lo / Hi

Default for all Modes is “PEEP off” in PCV the maximum PEEP available will be limited to 6 cmH2O. If PEEP is set, the default “PEEP Alarm” will be ± 50 % in the range 0 to 30 cmH2O The Rate or BPM alarm is to be the set value ± 50 % or in SIMV mode Lo 10 hi 20 BPM.

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Repair and Calibration Maintenance Manual

1. Technical Description

Frontline Sirius®

Figure 3 Inspired Gas Flow

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1. Technical Description

Frontline Sirius®

Figure 3a Absorber Pneumatic Schematic

A B C D E F G H I J K L M N

32

Manometer Inspiratory Non-return Valve Patient Inspiratory Connector Patient Expiratory Connector Expiratory Non-return Valve & PEEP Valve Canister(s) APL Valve Oxygen Sensor Port Absorber Bypass Valve APL Exhaust Valve Fresh Gas Port Bag/Vent Valve Ventilatory Port Bag Port

Repair and Calibration Maintenance Manual

1. Technical Description

Frontline Sirius®

Figure 4 Sirius 3000 Pneumatic Schematic

A B C D E F G H J K L M N P

O2 Pipeline O2 Cylinder Yoke N2O Pipeline N2O Cylinder Yoke Air Pipeline Air Cylinder Yoke ON/OFF– N2O/AIR Switch Reservoir Oxygen Failure Alarm O2 Shut Off Valve N2O/AIR Interlock Valve Air Valve Air Take Over Valve O2 Secondary Regulator

Repair and Calibration Maintenance Manual

Q R S T V W X Y Z

N2O Secondary Regulator Flow Meters Backbar O2 Flush Common Gas Outlet Blow Off Valve O2 HP Outlet Aux Flow Meter Hypoxic Link System

33

1. Technical Description

1.2.4

Frontline Sirius®

6700 8700 Principles of Operation

For active inspiration, the flow control calve is opened to provide a specific gas flow into the bellows assembly. Simultaneously the expiratory solenoid closes and pressure is generated in the bellows assembly producing an inspiratory flow to the patient. The flow and pressure measured and monitored by the microprocessor feedback system. Expiration occurs when the flow control valve is closed and the expiratory solenoid opens and releases the gas from the bellows assembly. In PCV mode the set pressure is achieved during inspiration and maintained at that level by allowing a controlled bypass through the expiratory valve. This allows the required pressure level to be maintained whilst compensating for any fresh gas flow into the patient circuit. For expiration the expiratory solenoid is opened which releases the gas from the bellows assembly. During all modes of ventilation an autozero is periodically applied to the flow sensors just prior to a breath being delivered; at this point there is no flow through the sensors, this ensures that the measured values are maintained as accurately as possible regardless of environmental variations.

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2. Removal / Replacement Instructions

Frontline Sirius®

2.

Removal / Replacement Instructions

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Frontline Sirius®

2. Removal / Replacement Instructions

Notes

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2. Removal / Replacement Instructions

Frontline Sirius®

When any repair or exchange is performed on internal components, a complete check must be made on all functions. A complete overall performance check must also be performed when any replacements or repairs have been completed.

2.1

Removal of Outer Cases

Figure 5 Removal of Top Surface Remove the 4 screws shown here (black circles are to indicate where screws are located) and lift the top cover off.

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Frontline Sirius®

2. Removal / Replacement Instructions

Remove bottom screw as shown

Remove top left screw as shown

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2. Removal / Replacement Instructions

Frontline Sirius®

Remove top right screw as shown

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2. Removal / Replacement Instructions

Frontline Sirius®

Ensure work surface is clear then slide front cover forwards in the direction shown.

Figure 6 Removal of Front Moulding

Figure 7 Front of Machine

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2. Removal / Replacement Instructions

Figure 8 Close up of the Front of Machine

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Frontline Sirius®

2. Removal / Replacement Instructions

Figure 9 Rear of Machine (Not necessary for Routine Service) Removal of back - Remove all pipelines and cylinders before removing screws and GCX. 42

Repair and Calibration Maintenance Manual

Frontline Sirius®

2. Removal / Replacement Instructions

Figure 10 Location of Rear Screws

Test Points Remove small panel for partial access, remove larger panel for complete access. Fuses

Figure 11 Part rear Panel Removed Repair and Calibration Maintenance Manual

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2. Removal / Replacement Instructions

Frontline Sirius®

Regulators

Figure 12 Complete Rear Panel Removed

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2.2

2. Removal / Replacement Instructions

Mechanical Hypoxic Guard Block

2.2.1 Introduction. The hypoxic guard prevents the operator from administering a mixture of gases which contain less than 21% oxygen, to achieve this, the oxygen and nitrous oxide control valves are linked via a set of gears. Any attempt to reduce the flow of oxygen or to increase the nitrous oxide flow to a level which would result in a oxygen concentration below this, results in the nitrous oxide valve closing or the oxygen valve opening to maintain the 21% minimum oxygen concentration.

The flow meter has a minimum oxygen flow “Basal Flow” which is only turned off via the main system ON/OFF switch.

•

The hypoxic guard is factory set and requires only routine calibration checks.

•

If during routine checking any of the calibration results are found to be out of specification some adjustment can be made to correct this and this is described later in this section, this should be done with extreme caution.

•

If due to damage or wear it is deemed necessary to replace the hypoxic guard valve block, a calibrated unit can be ordered which will be supplied with a test sheet which gives the regulator output pressures required for correct setting.

•

The flow control valve cartridges should not be dismantled, they are gas specific and require no servicing and cannot be repaired.

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2. Removal / Replacement Instructions

Frontline Sirius®

2.2.2 Calibration of Hypoxic Guard system In normal use the Hypoxic Guard unit requires only routine calibration checks, any variations outside the specified range should be investigated by checking that the nitrous oxide and air flow valves are shutting correctly (see section 2.4) or Setting the Basal Flow (see section 2.3) depending on the nature of the fault. If the calibration is faulty the recommended course of action is to replace the block with a calibrated replacement unit from Blease. It is possible to recalibrate the block provided that the valves have not become damaged (the precision valves should never be dismantled, internal damage to the seat or needle will not be visible to the eye but can make the valve unusable). If it is necessary to recalibrate the block then the following method can be used, it should be noted that this operation can take some time for the inexperienced engineer to master and should only be used if a replacement block is not available, if it proves impossible to achieve a satisfactory result then the precision valves are most likely to have become damaged and a new block is the only solution.

2.2.3 Calibration procedure. For the purpose of this procedure we will assume you have removed the front cover and removed the following parts from the Hypoxic block, the valve knobs, (remove end label and undo M3 retaining nut), the idler gear, (release by undoing the M4 nut and pulling the gear and bush from their shaft). The oxygen stop arm and the oxygen gear, this runs on a thread on the body of the oxygen valve, the stop screw can be left in place. (see fig 14)

46

1.

The first step is to ensure that the Air and Nitrous oxide valves are shutting fully and not overly tight, follow the procedure “Setting Valve shut off stop” (see section 2.4)

2.

As we are doing a full calibration you should set the hypoxic regulators to a ‘start’ setting of 30 psi, (see Mechanical hypoxic Guard Regulator Adjustment, section 2.6)

3.

The next stage is to set the Oxygen Basal flow, fit the oxygen gear to the valve and screw it fully on but DO NOT tighten it, it must be free running.

4.

Slide the oxygen stop arm onto the valve shaft and push it up to the oxygen gear just fitted, you will notice there is a groove around the gear into which the small drive ‘dog’ on the back of the stop should fit.

Repair and Calibration Maintenance Manual

Frontline Sirius®

2. Removal / Replacement Instructions

5.

Turn the stop arm clockwise until it hits the stop screw, and turn the oxygen gear anti-clockwise until you feel the drive ‘dog’ hit the end of the groove, (this should give about one full turn of the gear from its fully back position).

6.

There must be a small clearance between the gear face and the back face of the stop arm to ensure that the only point of contact is the ‘drive dog’ a 0.005in feeler gauge can be used or the thickness of a piece of standard writing paper is a useful alternative (see fig 16).

7.

Turn the machine on so that you have an oxygen supply to the flow meter.

8.

You must now hold the stop arm against the stop screw in a clockwise direction and the gear turned fully anti-clockwise and hitting the ‘drive dog’.

9.

Turn the shaft of the valve so that oxygen starts to flow and adjust the flow to the prescribed Basal flow level (still holding the gear and stop arm in position, when this is achieved tighten the two grub screws on the stop arm.

10.

The stop screw height must now be adjusted, turn the valve a full turn anti-clockwise and check that it just clears the top of the stop screw, if not adjust the stop by screwing it in till the arm JUST clears and tighten the lock nut and recheck that the arm hits the stop when turned clockwise and clears the top when turned anticlockwise.

11.

The ‘Idler gear’ must now be meshed to link the two valves, turn the stop arm clockwise to the stop and hold, and turn the oxygen gear fully anti-clockwise, (as in 8) this should give you the ‘basal flow’ showing on the oxygen flow meter. Turn the nitrous oxide flow up to approx 400ml and whilst holding the stop and gear in position carefully insert the idler gear and its bush onto it’s shaft and meshing it’s teeth with the oxygen and nitrous oxide gears, then fit the idler gear nut.

12.

The unit can then be checked for performance against the calibration test sheet, the flow rates on this sheet are guide lines of what should be achieved but the definitive reading is always the oxygen analyser reading, it is recommended that two analysers are used to ensure accuracy.

13.

If the calibration is not correct it will be necessary to ‘fine tune’ by adjusting the hypoxic regulators within the limits prescribed on the test sheet.

14.

If the desired results are still not reached then the gears (step11) must be reset to give the required effect. If the oxygen level is high then the gears will need to be ‘meshed’ with the nitrous flow at 450 or 500ml if the level is low the opposite would be needed. This adjustment and adjustment of the regulator pressures should allow calibration of the unit.

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Frontline Sirius®

2. Removal / Replacement Instructions

Notes

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Frontline Sirius®

2.3

2. Removal / Replacement Instructions

Setting Oxygen Basal Flow

If the Basal flow has altered during normal use, (this can occur if the valve has been turned down with excess force, reducing the flow, or has increased sometimes due to settling in of the regulators) the following method can be used to restore the correct flow often without the need to recalibrate the entire hypoxic guard block.

1. Remove the front cover (see section 2.1) and turn all flow controls to minimum, turn the machine on and allow basal flow on the oxygen to stabilize for a few minutes. 2. There are two grub screws holding the oxygen stop arm to the valve shaft, holding the stop arm tight against the stop screw slightly slacken the two screws and turn the valve shaft until the basal flow is within limits and retighten the grub screws. 3. Check that when the valve is opened that at its next complete revolution that the stop arm clears the top of the stop screw and that on closing it engages firmly with the stop screw (see fig 16), if not the screw may be adjusted by slackening its lock nut and screwing the stop in or out to achieve this. 4. Carry out a full check of the calibration of the Hypoxic Guard.

Small variations from the specified Basal flow can usually be rectified using the above method, if this does not give a satisfactory result it is possible that if the flow had been shut off completely that the valve seat may have been damaged, in these cases it may be necessary to replace the block with a new calibrated unit.

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Frontline Sirius®

2. Removal / Replacement Instructions

Figure 13 Assembled Hypoxic Guard Unit

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Repair and Calibration Maintenance Manual