VIASYS Vmax Encore Product manual

L2707 Rev. A
© 2005 VIASYS®Respiratory Care Inc.
Technical Reference Manual
Vmax Encore

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Vmax Encore Technical Reference Manual
COPYRIGHT AND TRADEMARK NOTICES
© 2005 SensorMedics Corporation
All rights reserved. No part of this document may be reproduced, stored, or transmitted in
any form or by any means without the written permission of SensorMedics Corporation,
except as specifically permitted under the copyright laws of the United States of America.
VIASYS and the VIASYS logo are registered trademarks of VIASYS Healthcare Inc. Vmax,
Autobox, MicroGard, and FreeFlow are trademarks of VIASYS Healthcare Inc. Perma Pure
is a registered trademark of Perma Pure, Inc. Nafion is a registered trademark of E.I. du
Pont de Nemours and Company. Microsoft and Windows are registered trademarks or
trademarks of Microsoft Corporation. Other brands and their products are trademarks of
their respective holders and should be noted as such.
COMPANY INFORMATION
www.viasyshealthcare.com
USA
SensorMedics Corporation
1100 Bird Center Drive
Palm Springs, CA 92262
Telephone: [phone]
[phone]
Fax: [phone]
Authorized European Representative
VIASYS Healthcare GmbH
Leibnizstrasse 7
97204 Hoechberg
Germany
Telephone: [phone]
Fax: [phone]

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PRECAUTIONS
•Caution: Federal law restricts this device to sale by, or on order of, a physician.
•Caution: This device is not suitable for use in the presence of flammable anesthetics.
•Service of this device is restricted to factory-trained personnel.
EQUIPMENT CLASSIFICATION
Classification of the equipment described in this manual:
•Class 1
•Type BF Defibrillator Proof (ECG Module)
•Type B (Vmax®and Vmax Spectra 62J/62W)
•Mode of operation: Continuous
The Vmax Encore and Vmax Spectra 62J/62W comply with the Medical Device Directive
MDD 93/42/EEC and have been approved to carry the CE Mark shown below.

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Contents
CONTENTS
Copyright and Trademark Notices - - - - - - - - - - - - - - ii
Company Information - - - - - - - - - - - - - - - - - - - - ii
Precautions - - - - - - - - - - - - - - - - - - - - - - - - - iii
Equipment Classification - - - - - - - - - - - - - - - - - - - iii
Chapter 1
Introduction
Vmax Encore Series Overview - - - - - - - - - - - - - - - 1–1
Vmax Instrument Configurations - - - - - - - - - - - - - - 1–1
System Components- - - - - - - - - - - - - - - - - - - - 1–6
Vmax Encore Series Specifications - - - - - - - - - - - 1–16
Chapter 2
System Description
General - - - - - - - - - - - - - - - - - - - - - - - - - - 2–1
Block Diagrams - - - - - - - - - - - - - - - - - - - - - - 2–5
Mass Flow Sensor Board - - - - - - - - - - - - - - - - 2–13
Analyzer Controller Board - - - - - - - - - - - - - - - - 2–26
Pressure Board - - - - - - - - - - - - - - - - - - - - - 2–27
Solenoid Board - - - - - - - - - - - - - - - - - - - - - 2–27
Chapter 3
Maintenance and Troubleshooting
Maintenance- - - - - - - - - - - - - - - - - - - - - - - - 3–1
Troubleshooting - - - - - - - - - - - - - - - - - - - - - 3–23
Replacement Parts - - - - - - - - - - - - - - - - - - - 3–29

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CHAPTER 1
INTRODUCTION
VMAX ENCORE SERIES OVERVIEW
This manual provides procedures relevant to servicing, troubleshooting, and repairing the Vmax
systems described in the following section. These procedures are intended for service and support
personnel who have been trained and are authorized to service the Vmax systems.
VMAX INSTRUMENT CONFIGURATIONS
The Vmax Encore Series consists of four basic instrument configurations. All instruments can be
ordered alone or with a selection of optional housings: a highly mobile cart, a mobile console, or a
stationary table. These configurations can be utilized separately or hardware/software components
can be combined in a number of ways to meet the needs of any specific cardiopulmonary
laboratory. The four available instrument configurations are as follows:
•Vmax Encore 20 Pulmonary Spirometry Instrument
•Vmax Encore 22 Pulmonary Function Analysis Instrument
•Vmax Encore 29 Cardiopulmonary Exercise Testing Instrument
•Vmax Encore 229 Pulmonary Function/Cardiopulmonary Exercise Testing Instrument
The Vmax Encore module can be positioned horizontally or vertically. The module can have a high
profile in the horizontal position (a wide profile in the vertical position); or the module can have a
low profile in the horizontal position (a narrow profile in the vertical position), depending on the
model. The maximum height in the horizontal position (width in the vertical position) is 15.24 cm.
Vmax Encore 20, 20c, 29c, and 29s have the low (narrow) profile.
By including or excluding hardware or software features, ten other configurations are available,
making a total of 14 different instruments. These ten other configurations are as follows:
•Vmax Encore 20c Pulmonary Spirometry Instrument
•Vmax Encore 22d Pulmonary Function Analysis Instrument
•Vmax Encore 22lv Pulmonary Function Analysis Instrument
•Vmax Encore 29c Cardiopulmonary Exercise Testing Instrument
•Vmax Encore 29n Cardiopulmonary Exercise Testing Instrument
•Vmax Encore 29s Cardiopulmonary Exercise Testing Instrument
•Vmax Encore 229c Pulmonary Function/Cardiopulmonary Exercise Testing Instrument
•Vmax Encore 229d Pulmonary Function/Cardiopulmonary Exercise Testing Instrument
•Vmax Encore 229lv Pulmonary Function/Cardiopulmonary Exercise Testing Instrument
•Vmax Encore 229n Pulmonary Function/Cardiopulmonary Exercise Testing Instrument

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Optional for all instruments, except the Vmax Encore 20c Pulmonary Spirometry Instrument,
is the Vmax Encore 62J/62W Autobox Body Plethysmograph.
VMAX ENCORE 20 PULMONARY SPIROMETRY INSTRUMENT
The Vmax Encore 20 is designed to be used as a lightweight, portable office or bedside pulmonary
screening spirometer with the capability of controlling the Vmax Encore 62J/62W Autobox.
The Vmax Encore 20 includes the following components:
•The Encore module containing the Analyzer Assembly
•Desktop or notebook computer
•Program software
•Printer
•Mass flow sensor
VMAX ENCORE 22 PULMONARY FUNCTION ANALYSIS INSTRUMENT
The Vmax Encore 22 is designed to be used as a full-featured Pulmonary Function instrument with
the capability of controlling the Vmax Spectra 62J/62W Autobox.
The Vmax Encore 22 includes the following major components:
•The Encore module containing the Analyzer Assembly and the Pneumatics Assembly
•Desktop or notebook computer
•Program software
•Printer
•Mass flow sensor
•Automated breathing valve
•100% oxygen cylinder with gas valve
•DLCO mix cylinder with gas valve
VMAX ENCORE 29 CARDIOPULMONARY EXERCISE TESTING INSTRUMENT
The Vmax Encore 29 is designed to be used as a full-featured Metabolic Measurement instrument
with the capability of controlling the Vmax Encore 62J/62W Autobox.
The Vmax Encore 29 includes the following components:
•The Encore module containing the Analyzer Assembly and the Pneumatics/Fan Assembly
•Desktop or notebook computer
•Program software
•Printer

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•Mass flow sensor
•One-way breathing valve with tubing
•26% oxygen calibration cylinder with gas regulator
•4% carbon dioxide, 16% oxygen calibration cylinder with gas regulator
VMAX ENCORE 229 PULMONARY FUNCTION ANALYSIS/
CARDIOPULMONARY EXERCISE TESTING INSTRUMENT
The Vmax Encore 229 combines all the features and options of both the Vmax Encore 22 and
Vmax Encore 29 instruments with the capability of controlling the Vmax Encore 62J/62W Autobox.
The Vmax Encore 229 includes the following components:
•The Encore module containing the Analyzer Assembly and the Pneumatics/Fan Assembly
•Desktop or notebook computer
•Program software
•Printer
•Mass flow sensor
•Automated breathing valve
•One-way breathing valve with tubing
•100% oxygen cylinder with gas valve
•DLCO mix cylinder with gas valve
•26% oxygen calibration cylinder with gas valve
•4% carbon dioxide, 16% oxygen calibration cylinder with gas valve
VMAX ENCORE 20c PULMONARY SPIROMETRY INSTRUMENT
The Vmax Encore 20c is designed to perform the same tests as the Vmax Encore 20 instrument
mentioned above but without the capability of controlling the Vmax Encore 62J/62W Autobox.
VMAX ENCORE 22d PULMONARY FUNCTION ANALYSIS INSTRUMENT
The Vmax Encore 22d is designed to perform the same tests as the Vmax Encore 22 instrument
mentioned above with the exception of Gas Dilution Lung Volume testing which is not provided.
The Vmax Encore 22d has the same components as the Vmax Encore 22 except the Analyzer
Assembly does not contain an O2sensor or a CO2analyzer and O2/CO2calibration gas is not
included.
VMAX ENCORE 22lv PULMONARY FUNCTION ANALYSIS INSTRUMENT
The Vmax Encore 22lv is designed to perform the same tests as the Vmax Encore 22 instrument
mentioned above with the exception of Diffusing Capacity testing which is not provided. The Vmax

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Encore 22lv has the same components as the Vmax Encore 22 except the Analyzer Assembly
does not contain a Multi-gas analyzer and DLCO mix calibration gas is not included.
VMAX ENCORE 29c CARDIOPULMONARY EXERCISE TESTING INSTRUMENT
The Vmax Encore 29c is designed to perform the same tests as the Vmax Encore 29 instrument
mentioned above with the exception of Mixing Chamber exercise testing which is not provided.
The only optional test available is Indirect Calorimetry for mechanically ventilated patients. The
Vmax Encore 29c has the same components as the Vmax Encore 29 except all necessary valves
and plumbing normally located in the Pneumatics/Fan Assembly are housed in the Analyzer
Assembly and there is no Pneumatics/Fan Assembly.
VMAX ENCORE 29n NUTRITIONAL ASSESSMENT INSTRUMENT
The Vmax Encore 29 is designed to be used as a mobile Nutritional Assessment instrument with
the capability of controlling the Vmax Encore 62J/62W Autobox.
The Vmax Encore 29n includes the following major components:
•The Encore module containing the Analyzer Assembly and the Pneumatics/Fan Assembly
•Desktop or notebook computer
•Program software
•Printer
•Mass flow sensor
•Dilution canopy
•26% oxygen calibration cylinder with gas regulator
•4% carbon dioxide, 16% oxygen calibration cylinder with gas regulator
VMAX ENCORE 29s CARDIOPULMONARY EXERCISE TESTING INSTRUMENT
The Vmax Encore 29s performs the same tests and has the same components as the Vmax
Encore 29c. The Vmax Encore 29s does not provide spirometry testing and does not have a
pneumatics/fan assembly.
VMAX ENCORE 229c PULMONARY FUNCTION/CARDIOPULMONARY
EXERCISE TESTING INSTRUMENT
The Vmax Encore 229c performs the same tests as the Vmax Encore 229, with the exception of
mixing chamber exercise testing and indirect calorimetry testing. The Vmax Encore 229c has the
same components as the Vmax Encore 229, except that the pneumatics/fan assembly does not
contain a mixing chamber. The ECG pod box is not included with this instrument.

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VMAX ENCORE 229d PULMONARY FUNCTION/CARDIOPULMONARY
EXERCISE TESTING INSTRUMENT
The Vmax Encore 229d is designed to perform the same tests as the Vmax Encore 229 instrument
mentioned above with the exception of Gas Dilution Lung Volume testing which is not provided.
The Vmax Encore 229d has the same components as the Vmax Encore 229 except the Analyzer
Assembly does not contain an O2sensor or a CO2analyzer and O2/CO2calibration gas is not
included.
VMAX ENCORE 229lv PULMONARY FUNCTION/CARDIOPULMONARY
EXERCISE TESTING ANALYSIS INSTRUMENT
The Vmax Encore 229lv is designed to perform the same tests as the Vmax Encore 229 instrument
mentioned above with the exception of Diffusing Capacity testing which is not provided. The Vmax
Encore 229lv has the same components as the Vmax Encore 229 except the Analyzer Assembly
does not contain a Multi-gas analyzer and DLCO mix calibration gas is not included.
VMAX ENCORE 229n CARDIOPULMONARY EXERCISE TESTING INSTRUMENT
The Vmax Encore 229n combines all the features, options and applications of both the Vmax
Encore 22 and Vmax Encore 29n instruments.
VMAX 62J/62W AUTOBOX BODY PLETHYSMOGRAPH
The Vmax 62J/62W Autobox is a full-featured Body Plethysmograph designed to interface with any
Vmax instrument except the Vmax Encore 20c Instrument.
The Vmax 62J/62W includes the following major components.
•Cabin with adjustable chair
•Electronics Compartment
•Mass Flow Sensor
•16% O2, 4% CO2Calibration gas cylinder with Gas Valve

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SYSTEM COMPONENTS
This section provides a general description of the components that combine to form the Vmax
cardiopulmonary instruments; more detailed descriptions of each system can be found in the
chapter ”System Description” on page 1.
Vmax Encore 20 Pulmonary Spirometry Instrument
Measurement components in the Vmax Encore 20 Pulmonary Spirometry Instrument:
•Pressure Transducers (3)
•Barometric Pressure Transducer
•Direction Pressure Transducer
•Mouth Pressure Transducer
•Temperature Transducer
•Mass Flow Sensor Input
•Box Pressure Input
Vmax Encore 22 Pulmonary Function Analysis Instrument
Measurement components in the Vmax Encore 22 Pulmonary Function Analysis Instrument:
•Pressure Transducers (3)
•Barometric Pressure Transducer
•Direction Pressure Transducer
•Mouth Pressure Transducer
•Temperature Transducer
•Mass Flow Sensor Input
•Box Pressure Input
•Multi-gas Analyzer
•O2Sensor
•CO2Analyzer

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Vmax Encore 29 Cardiopulmonary Exercise Testing Instrument
Measurement components in the Vmax Encore 29 Cardiopulmonary Exercise Testing Instru-
ment:
•Pressure Transducers (3)
•Barometric Pressure Transducer
•Direction Pressure Transducer
•Mouth Pressure Transducer
•Temperature Transducer
•Mass Flow Sensor Input
•Box Pressure Input
•O2Sensor
•CO2Analyzer
Vmax Encore 229 Pulmonary Function/Cardiopulmonary Exercise Testing Instrument
Measurement components in the Vmax Encore 229 Pulmonary Function/Cardiopulmonary
Exercise Testing Instrument:
•Pressure Transducers (3)
•Barometric Pressure Transducer
•Direction Pressure Transducer
•Mouth Pressure Transducer
•Temperature Transducer
•Mass Flow Sensor Input
•Box Pressure Input
•Multi-gas Analyzer
•O2Sensor
•CO2Analyzer
All Systems
Other components included on all systems:
•Power Supply Transformer with Circuit Breaker
•Signal Processing and Valve Control Circuits
•Remote Start Input
•Printer Output
•Peripheral Device (POD) Input/Output (except on Vmax Encore 20 Spirometer)

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•Sample Pump (except on Vmax Encore 20 Spirometer)
•Ambient Temperature Sensor
•Cooling Fan
Pneumatics/Fan Assembly
The Pneumatics/Fan Assembly manages the flow of the various gases delivered and analyzed
during calibration and testing.
Vmax Encore 22 Pulmonary Function Lab
Pneumatic components in the Vmax Encore 22 Pulmonary Function Lab:
•Solenoid Valves (6)
•High-capacity Demand Regulator
•3-way High-flow Input Valve for Oxygen and Diffusion Gases
•Perma Pure Calibration Tubing
Vmax Encore 29 Metabolic Measurement LC Cart
Pneumatic components in the Vmax Encore 29 Metabolic Measurement LC Cart:
•Solenoid Valves (5)
•Mixing Chamber/Blower Combination Unit with Mass Flow Sensor Adapter
•Blower Failure Alarm with 9V Battery
•Perma Pure Calibration Tubing
Vmax Encore 229 Pulmonary Function/Metabolic LC Cart
Pneumatic components in the Vmax Encore 229 Pulmonary Function/Metabolic LC Cart:
•Solenoid Valves (11)
•High-capacity Demand Regulator
•3-way High-flow Input Valve for Oxygen and Diffusion Gases
•Mixing Chamber/Blower Combination Unit with Mass Flow Sensor Adapter
•Perma Pure Calibration Tubing

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MASS FLOW SENSOR
The Vmax Encore Series instruments measure inspired and expired flow directly by using the
highly accurate and very stable Mass Flow Sensor. The computer program electronically integrates
flow signals to obtain volume measurements and makes the Mass Flow Sensor linear.
Figure 1-1 Mass Flow Sensor.
The electronic circuit of the Mass Flow Sensor monitors the resistance of the sensor filaments to
determine their temperatures, so it is important that only the resistances of the filaments are
measured. A new technique, Kelvin Sensing, and exclusive design are incorporated in the Vmax
Encore Mass Flow Sensor to eliminate the influence of connector and cable resistance in the
measurements.
The Mass Flow Sensor uses two metallic filaments to sense gas flow rate: a sensing filament and a
reference filament. The reference filament tracks the temperature of gas whereas the sensing
filament is maintained at a preset temperature above that of the reference filament. As gas flows
through the sensor, the gas molecules remove heat from the sensing filament. To maintain the
sensing filament at the same offset temperature, more power must be delivered to the sensing
filament. This additional power is an accurate measurement of the mass flow rate through the
sensor. Unlike volumetric flow, mass flow measurements are unaffected by changes in air pressure
or temperature.
Since the reference filament resistance is determined by its temperature, the Kelvin Sensing
provides accurate reading of the gas temperature as well. The relatively low thermal mass of the

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filaments also makes it possible to track the rapidly changing gas temperatures encountered in all
Vmax Encore diagnostic functions.
MULTI-GAS ANALYZER
The rapid-response Multi-gas Analyzer provides a real-time measurement of Carbon Monoxide
(CO) and Methane (CH4). Measurement of the gas concentration is made using a Non-dispersive
Infrared (NDIR) technique. This technique involves directing a beam of infrared energy through a
sample of the gas to be analyzed and measuring the amount of infrared energy that is absorbed.
In order to measure multiple gases in a single sample, the analyzer incorporates an assembly with
multiple filters and detectors; this removes the requirement for the motorized filter wheel common
on other infrared analyzers. The wavelength of each band is carefully chosen to measure only the
desired gas.
O2Sensor
The oxygen sensor works on the principle of the electrochemical mechanism. It consists of a metal
lead as the anode and a potassium hydroxide solution as the electrolyte.
CAUTION!During the course of servicing the equipment, wear eye and hand pro-
tection if you notice liquid on or around the O2sensor, and heed all
safety notices that are included in the procedure.
WARNING!The O2sensor contains 10% Potassium Hydroxide (KOH), a CORRO-
SIVE chemical. Contact with Potassium Hydroxide may cause irrita-
tion or severe chemical burns. Exposure may lead to acute and
chronic damage to the individual.
R35 – Causes severe burn
R42 – May cause sensitization by inhalation
R36/37/38 – Irritating to eyes, respiratory system and skin
WARNING!The O2sensor contains lead (Pb), a chemical known to the state of
California to cause cancer, birth defects, or other reproductive harm.
Exposure may lead to acute and chronic damage to the individual and
the fetus of a pregnant woman.

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Emergency First Aid Procedures
In case of contact with the skin or eyes, immediately flush with water for at least 15
minutes and remove all contaminated clothing. Get medical attention immediately.
If ingested, give large amounts of water and DO NOT INDUCE VOMITING. Obtain med-
ical attention immediately.
If inhaled, remove to fresh air and obtain medical attention immediately.
Disposal
Waste must be disposed of in accordance with Federal, State, and Local environmen-
tal control regulations.
The fast-response oxygen sensor is based on the electrochemical principle. The sensor provides
the fast response time necessary for real-time breath-by-breath gas analysis. During operation, the
oxygen is reduced at the cathode, generating a current that is proportional to the oxygen content in
the sample.
CARBON DIOXIDE ANALYZER
As with the Multi-gas Analyzer discussed above, the Carbon Dioxide (CO2) Analyzer uses the
rapid-response Non-dispersive Infrared (NDIR) measurement technique. As with the oxygen
analyzer, the sample chamber size has been greatly minimized to enhance response
characteristics.

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AUTOMATED BREATHING VALVE
Figure 1-2 Automated Breathing Valve.
The automated breathing valve is used for the following tests: FRC, DLCO, max pressures,
compliance, SBO2, P100, and intra-breath DLCO. The pneumatically driven valve automatically
switches the patient between the various breathing circuit configurations, and between room air
and the test gases. The computer program determines timing and control.
The valve is mounted on the flow sensor and is easily disinfected.
ONE-WAY BREATHING VALVE
The One-way Breathing Valve is used for mixing chamber exercise testing. The valve employs
silicon spiral diaphragms for low flow resistance and easy disinfecting.

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MIXING CHAMBER/BLOWER
A 2.6-liter mixing chamber is located in the Pneumatics/Fan Assembly. This chamber is used for
mixing expired gas during exercise and calorimetry testing. The chamber also houses the variable
volume, high capacity blower used for dilution testing. The blower volume is controlled by the
computer and is continuously variable from 12–60 LPM.
The blower’s on/off switch is located on the front of the Pneumatics/Fan Assembly. Safety circuitry
will automatically turn the blower up to full volume if communication with the computer is lost for
any reason.
A battery-powered alarm will sound if the blower’s on/off switch is in the on position and there is a
power loss to the Analyzer Assembly.
DEMAND REGULATOR
A high-capacity Demand Regulator is located in the Pneumatics Assembly. This regulator is used
to deliver test gases (oxygen or diffusion mixture) to the patient on inspiratory demand during the
FRC, SBO2, P100, intra-breath, compliance, and DLCO tests. The delivered flow range is 0–6 LPS.
PERMA PURE®NAFION®DRYING TUBE
The calibration gas and the patient's exhaled gas pass through a Perma Pure drying tube before
entering the gas analyzers. The absorption and evaporation properties of the Nafion material in the
drying tube ensure that the relative humidity in the exhaled gas and in the calibration gas is
equilibrated to ambient conditions (room air) when they are sampled in the analyzer. This results in
a high degree of accuracy in the actual gas concentration measurements and removes the need for
external drying crystals. The tube is wrapped in protective braiding to prevent pinching and
crimping.
SOLENOID AND DEMAND VALVE CONTROL
All flushing, sealing, and gas flow control is provided by an integrated system of solenoid valves,
one-way valves, and a high-capacity demand valve. The computer controls these valves
automatically. The computer program is designed to take the operator through the appropriate
steps of any given test, thereby insuring that all valves are in the correct position at all times. The
internal pneumatic connections are of rigid construction and are tested at elevated pressures to
insure excellent, long-term seals.
TEMPERATURE SENSOR
A temperature sensor is located inside the air circulation inlet port on the Analyzer Assembly to
measure ambient room temperature. This makes operator-entry of the room temperature from a
separate room thermometer unnecessary.

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BAROMETRIC PRESSURE SENSOR
A barometric pressure sensor is located in the Analyzer Assembly to continuously measure
ambient barometric pressure, making operator-entry of a reading from a barometer unnecessary.
This same sensor also measures changes in gas sample line pressure so that adjustments in gas
partial pressures can be calculated.
DIRECTION PRESSURE SENSOR
A direction pressure sensor is located in the Analyzer Assembly to determine the direction of the
flow signal. This sensor provides for automatic detection of inspiratory and expiratory volumes.
MOUTH PRESSURE SENSOR
A mouth pressure sensor is located in the Analyzer Assembly to measure respiratory pressures at
the mouth.
ANALOG I/O POD
An Analog I/O Pod is provided for interfacing external devices. The pod provides for the following
device interfaces:
•Eight analog input
•Four analog output
•Three TTL output
•One analog heart rate input or SMC 3-Lead ECG input