SensorMedics
Vmax Encore Technical Reference Manual Rev A
Technical Reference Manual
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Technical Reference Manual Vmax Encore
L2707 Rev. A © 2005 VIASYS® Respiratory Care Inc.
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 USA
Authorized European Representative
SensorMedics Corporation 1100 Bird Center Drive Palm Springs, CA 92262 Telephone: 800 231-2466 +1 714 283-2228 Fax: +1 714 283-8493
VIASYS Healthcare GmbH Leibnizstrasse 7 97204 Hoechberg Germany Telephone: +49 931 4972-0 Fax: +49 931 4972-423
www.viasyshealthcare.com
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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 L2707
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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 1–2
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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 O2 sensor or a CO2 analyzer and O2/CO2 calibration 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 L2707
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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 O2 sensor or a CO2 analyzer and O2/CO2 calibration 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% CO2 Calibration 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 • O2 Sensor • CO2 Analyzer
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Vmax Encore 29 Cardiopulmonary Exercise Testing Instrument Measurement components in the Vmax Encore 29 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 • O2 Sensor • CO2 Analyzer 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 • O2 Sensor • CO2 Analyzer 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) L2707
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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.
O2 Sensor 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 protection if you notice liquid on or around the O2 sensor, and heed all safety notices that are included in the procedure.
WARNING! The O2 sensor contains 10% Potassium Hydroxide (KOH), a CORROSIVE chemical. Contact with Potassium Hydroxide may cause irritation 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 O2 sensor 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 medical 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 environmental 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
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