Service Manual
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3100A High Frequency Oscillatory Ventilator Service manual
This document is protected by United States and International Copyright laws. This document may not be copied, reproduced, translated, stored in a retrieval system, transmitted in any form, or reduced to any electronic medium or machine-readable form, in whole or in part, without the written permission of CareFusion. Information in this document is subject to change without notice. This document is for informational purposes only and should not be considered as replacing or supplementing the terms and conditions of the License Agreement. © 2010 CareFusion Corporation or one of its subsidiaries. All rights reserved. 3100A is a registered trademark of CareFusion Corporation or one of its subsidiaries. All other trademarks are property of their respective owners. USA CareFusion 22745 Savi Ranch Parkway Yorba Linda, California 92887-4668
Authorized European Representative CareFusion Germany 234 GmbH Leibnizstrasse 7 97204 Hoechberg, Germany District Court Wuerzburg HRB7004
800.231.2466 tel +1.714.283.2228 tel +1.714.283.8493 fax
+49.931.4972.0 tel +49.931.4972.423 fax
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Literature number: 767161 Revision F
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767161 Rev. F
Service manual
3100A® High Frequency Oscillatory Ventilator
Contents Chapter 1
Introduction ...1–1
Warnings and Cautions ... 1–1 System Description ... 1–1 Component Description ... 1–2 Chapter 2
Maintenance Procedures...2–1
Patient Circuit Calibration Procedure ... 2–1 Ventilator Performance Checks ... 2–1 Scheduled Maintenance ... 2–2 2000 Hour Maintenance Procedure ... 2–3 4000 Hour maintenance Procedure ... 2–8 6000 Hour Maintenance Procedure ... 2–26 8000 Hour Maintenance Procedure ... 2–44 12000 Hour Maintenance Procedure... 2–70 Chapter 3
Diagrams ...3–1
System Block Diagrams ... 3–1 Schematic Diagrams... 3–2 Chapter 4
Assembly Drawings ...4–1
Chapter 5
Troubleshooting ...5–1
Pneumatic Failure ... 5–1 Electronic Failure ... 5–3 Mechanical Failure ... 5–5 Chapter 6
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Parts List ...6–1
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3100A® High Frequency Oscillatory Ventilator
Service manual
3100A HFOV
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767161 Rev. F
Service manual
Chapter 1
3100A® High Frequency Oscillatory Ventilator
Introduction
This manual contains all of the necessary technical information to repair the 3100A High Frequency Oscillatory Ventilator. To truly understand the operation of this ventilator you must also become familiar with the Operator’s Manual (PART NUMBER 767124).
Warnings and Cautions This manual contains important information concerning the prevention of bodily injury and the protection of the equipment. This information may be designated by either Warning or Caution whereby: Warning! A Warning designates information concerning the possibility of bodily injury to the patient, operator or others. Caution! A Caution designates information concerning the possibility of damage to the instrument or to other property.
System Description The 3100A HFOV uses a linear motor to oscillate a column of bias flow gas which flows in front of the motor. The column of air creates a pressure within the patient circuit by a variable reduction of the egress of a variable bias flow gas. The gas flow is restricted by the inflation of three mushroom valves mounted on the circuit. Two of the three inflation pressures can be varied to adjust the pressure. The third is a safety valve inflated via a solenoid valve which is de-activated whenever the Mean Airway Pressure is greater than 50 cmH2O or less than 20% of a variable maximum Mean Airway Pressure Alarm. We refer to the mushroom valves as Cap/Diaphragms. Anyone expected to perform emergency service repairs on this device should have three “KNOWN GOOD” Cap/Diaphragms. This column of Bias Flow Gas is then oscillated via a plate which is suspended by the rubber diaphragm which can be seen when the patient circuit is removed. The screws toward the center of the plate attach the plate to a coil of wire which is suspended within a permanent magnet. The coil is then excited with a square wave of adjustable amplitude, frequency and duty cycle. This serves to move the plate via the electromagnetic effects on the coil, causing an oscillating pressure wave dependent on the driving current through the coil and the collapsing or expanding magnetic field. The driving signal is generated by the Driver Controller Module which is located in the lower support column of the device just beneath the Driver Assembly. This module produces a square wave of adjustable frequency, amplitude, offset potential and duty cycle dependent on four user set potentiometers. Refer to the Operator’s Manual for further information on these controls. 767161 Rev. F
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3100A® High Frequency Oscillatory Ventilator
The pressures generated by the 3100A are measured by a transducer located in the upper Electronics Enclosure. A 1/8” tube leads from the ET Tube connection to the bulkhead. This line incorporates a positive flow to clear it of any condensation from the humidified Bias Gas. A length of coiled tubing prior to the transducer connection serves to filter out any components of the pressure wave which do not contribute to ventilation. The signal generated by the transducer is detected and conditioned on the Alarm Board which is located at the base of the Electronics Enclosure. If any alarm condition is occurring, the appropriate LED will be lit and the appropriate safety circuit activated. The position of the oscillating Driver is measured by a photo sensor at the rear of the Driver and displayed on the front of the instrument by the Driver Displacement Indicator Board. An elapsed time meter records the time during which the instrument has been turned on regardless of whether or not the driver is activated. Refer to the Theory of Operation Section in the Operator’s Manual for more detailed descriptions. The only ties between electricity and the pressures generated by the 3100A are the solenoid valve and the movement of the oscillating piston. This is very important in the troubleshooting of the system. Once the solenoid valve has been eliminated as a problem and the Mean Airway Pressure can be maintained and controlled by both the Adjust and Limit controls, the problem can be isolated to the Driver, or one of it is supporting components, including the Bellows/Water Trap Assembly and the Patient Circuit Body.
Component Description Lower Power Supply There are four separate power supplies generated in the Lower Power Supply Assembly. The ±15V DC and +5V DC originate on a separate subassembly mounted on a bracket of the larger assembly. The current ratings are 2A for the +5V DC supply, and 400mA for the ±15V DC supply. Both of the AC input lines are fused at 500mA. The fuses are used to drive all TTL logic IC’s and all bipolar operational amplifiers. All three are adjustable and the corresponding potentiometers are labeled on the circuit board. The remaining supply generated by the Lower Power Supply Assembly is the +60V DC supply. This power supply is simple in design utilizing a full-wave rectifier, a 9000µƒ capacitor and load resistors. Refer to the Interconnect Wiring Diagram for the schematic of this supply. It is used to develop the +24V DC on the Driver Controller Board and is the source of current for the PWM (See Driver Controller Module Theory of Operation).
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Introduction
Pneumatics Operation The pneumatics operation of the 3100A can be divided into six distinct pneumatic systems. Refer to the Pneumatics Diagrams in the 4000 hour procedure 770102. • Input from blender. • Bias flow. • Limit. • Pressure measurement. • Dump and control. • Driver cooling. Input from Blender The input gas from the mixed Air/O2 supply must be 40 - 60 psi and capable for flow of 40 LPM. This pressure will open a normally closed pressure switch which is set to open at 30psi. The switch is factory adjusted. In parallel with the switch is a 75 psi pop-off valve which is self resetting. This input gas then goes to PR4 (Pressure Regulator) where the input pressure is then fed to PR1, PR2, PR3, PR6, and PR7 for other functions. Bias Flow PR7/PR1 feeds the flow meter on the front panel and supplies the pressure necessary for the maximum flow rate of the 3100A which is 40 LPM. To adjust this regulator, simply open the front panel flow meter fully CCW and adjust PR7/PR1 for a reading of 40 LPM. This bias flow leaves the electronics enclosure after passing a factory adjusted 5 psi pop-off valve. The air would then be heated and humidified and finally be connected to the underside of the patient circuit assembly. This flow then creates a positive pressure inside the patient circuit. Limit PR2 reduces the pressure from PR4 to approximately .65 psi. There are three paths for air flow. First, there is a fixed orifice to atmosphere. Second, there is a variable orifice to atmosphere. Third, there is the LIMIT cap/diaphragm on the patient circuit. The cap/diaphragm will inflate to a user controlled pressure, dependent on the variable orifice. The pressure will be greatest when the variable orifice is fully closed. The inflation of the cap/diaphragm will occlude the opening in the patient circuit at the LIMIT valve just above the bias flow connection. The occlusion of this opening will allow the bias flow to create a pressure within the circuit and pressures which exceed the cap/diaphragm inflation pressure will bleed off through the opening. This inflation therefore sets a LIMIT for any point downstream in the patient circuit.
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3100A® High Frequency Oscillatory Ventilator
Pressure Measurement PR6 reduces the pressure from PR4 to approximately 135 cmH2O. This is passed to a tee fitting which leads to the pressure sense line and the pressure transducer. A length of coiled 1/8-inch tubing is used for coupling to the pressure transducer to eliminate noise. This pressure of 135 cmH2O is used to create a flow of air away from the pressure transducer and towards the measuring point on the patient circuit, removing any condensation in the humidified bias flow gas from the humidifier. Dump and Control PR3 reduces the pressure from PR4 approximately 3 - 7 psi under normal operating conditions. This is a user adjustment, located on the right side of the top cover, and should never exceed 7 psi when properly adjusted. This pressure is fed to the normally closed port of solenoid valve one. When the solenoid valve is energized this pressure inflates the DUMP cap/diaphragm. This cap/diaphragm is closest to the patient connection on the patient circuit and totally occludes the opening there. When any alarm condition is encountered which necessitates the opening of the DUMP valve, the solenoid valve is de-energized and the pressure at the cap/diaphragm will be vented to atmosphere through the normally open port of the solenoid valve allowing the pressure in the patient circuit to drop to atmosphere. PR3 also supplies pressure to the CONTROL cap/diaphragm. This pressure will not be as high as that at the DUMP cap/diaphragm because it is also sent to two variable orifices. FV1 at the bottom of the pneumatics enclosure is an adjustable flow restrictor and should be adjusted during the pneumatics alignment procedure in the adjustments section. The other variable orifice is the front panel Paw adjust valve. Closing this restrictor with a clockwise turn will cause greater occlusion of the opening in the patient circuit body at the CONTROL valve. This is the last exit for the bias flow and restricting this outlet will cause a higher pressure in the patient circuit. Keep in mind that even if the CONTROL cap/diaphragm were inflated to maximum, some bias flow is allowed to escape through a separate hole near this valve as a safety feature. Driver Cooling The requirements of the compressor air source used to cool the driver are pressure of 40 - 60 PSIG with capability of flow at 10-15 LPM. This input gas is sensed at a 30 psi, normally closed, pressure switch. The switch will open at a pressure greater than 30 PSIG. This input gas is sensed at a 75 psi pop-off valve which will attempt to release pressures above 75 psi. It is self resetting. PR5 reduces this input pressure to approximately 20 psi and feeds into an air flow amplifier on the underside of the driver assembly. This device entrains room air in with the flow of compressed air to enhance the cooling of the driver. For 1.5 ohm driver assemblies (766860) PR5 is set at approximately 15 LPM. For the 3 ohm driver assembly (772730), PR5 is set for ≈ 10 LPM.
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Introduction
Pressure Transducer Transducer Type The Pressure Transducer used in the 3100A is Model 143PC03D manufactured by Micro Switch, a division of Honeywell. It is a differential transducer with an input pressure range of ±2.5 psi. The excitation voltage is +10V DC generated on the Alarm Board. This voltage can be measured at TP5. The output characteristics are well beyond those necessary to accurately measure the 15 Hz waveform. Calibration It is necessary to check the calibration of the Pressure Transducer every 2000 hours of operation. Refer to the Maintenance Section of the manual for instructions on this and other regular maintenance requirements.
Alarm Board The Alarm Board in the 3100A can be broken down into several separate circuits which integrate to serve the following functions: • Driving the AUDIO buzzers. • Detecting and utilizing the battery. • Driving the warning and alarm LED’s. • Generating a signal to stop the oscillator when a pressure alarm has occurred. • Detecting the user adjustable Thumbwheel switches. • Detecting the pressure signals, Paw and ∆P. • Determining if an alarm has occurred. The signal generated by the pressure transducer comes on to the board at J1 pin 1 and is conditioned by three stages of U2, a quad operational amplifier. U2-A is a current amplifier. U2-C provides high frequency filtering and a voltage gain of three. This stage also incorporates an offset adjustment with potentiometer R6. U2-D provides adjustable gain with feedback potentiometer R2. Both potentiometers can be adjusted through the rear panel. TP1 (Test point one) provides easy measurement of the pressure signal using TP6 as a reference ground test point. See the Maintenance Section of this manual for instructions on performing this calibration. Input capacitors C2 and C3 provide input to quad operational amplifier U1-A allowing only changing pressure signals through. U1-C amplifies the negative portions of the pressure signal and this voltage is stored on capacitor C5 due to it is relatively long discharge time through R10. Similarly C1 stores the positive peaks of the pressure signal. The output of U3-C will be proportional to the difference between positive and negative peaks. This signal is sent to the “AMPLITUDE” digital panel meter and is commonly referred to as the ∆P measurement.
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3100A® High Frequency Oscillatory Ventilator
Oscillator Stopped Alarm Comparator U12-A compares a reference voltage of approximately 3V DC to the difference between the positive and the negative peak. If the difference voltage is less than approximately .3V DC (6 cmH2O on the digital panel meter labeled “AMPLITUDE”) then diode CR3 will not conduct. The output of the comparator will go to the low state creating an “OSC STOPPED” signal and activating the warning light. “OSC STOPPED ALARM DISABLE” is active high when the “START/STOP” front panel switch is in the stop mode and the LED is extinguished. This signal originates on the Driver Displacement Indicator Board. Mean Airway Pressure and Alarms Operational amplifier U11-D provides buffering and low pass filtering of the pressure signal. The average pressure or “MEAN AIRWAY PRESSURE” is sent out J2 pin 5 and 6 by way of voltage divider R47 and R40. The front panel Thumbwheel switches for minimum and maximum pressure alarms are adjustable resistance’s which provide feedback for operational amps U3-B and U3-A. The signal is generated by a 10V reference, Q1. The adjustable resistance of the Thumbwheels add 100Ω with each increase in the units digit, and 1KΩ with each increase in the tens digit. Quad comparator U5 is used to determine if a pressure alarm has occurred. The signal “MEAN HI” is used as a positive input on U5-A and U5-B. The negative input of U5-A is the “Set Min” signal selected by a Thumbwheel. The negative input of U5-B will be 20% of the signal “Set Max” selected by the other Thumbwheel. These comparisons determine if a low pressure alarm is occurring and the output of the comparator will be driven low if an alarm is occurring. Conversely, U5-C has its negative input tied to the signal “MEAN HI” and compares it to the full “Set Max” selected by the Thumbwheel switch. And U5-D has “MEAN HI” on the positive input and a fixed 2.5V on the negative. These comparisons determine if a high pressure alarm is occurring. The output of U5-C will be driven low when an alarm is occurring. The output of U5-D will be driven high when the “MEAN HI” signal is greater than 50 cmH2O or 2.5V DC. The conversion factor for voltage to pressure is (1 cmH2O = 50mV) or (1V = 20 cmH2O). The 3100A high pressure alarm is set by U5-D when the “MEAN HI” pressure signal rises above 50 cmH2O or 2.5V. This high level will be sensed at OR gate U10-D forcing its output high. This signal is then inverted by U14-B to turn the LED on the Alarm Display Board on. The output of U5-D is also used to trigger U6-A, a monostable multivibrator. This positive pulse will clock the output of U4-A high. U4-A can be reset by the operator pressing the “RESET” switch which will generate a reset pulse to U4-A via Q2. This should only be done after correcting the cause for the high pressure alarm as the DUMP valve will close again and the driver will begin to oscillate again. Keep in mind that the user adjustment to the LIMIT valve should prevent any pressure this high from ever being developed in the patient circuit. This alarm stops the oscillator, opens the DUMP valve and sounds the audio buzzer via U10 and U14 along with Q5 and associated circuitry.
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Introduction
When the “MEAN HI” signal falls below 20% of the “Set Max” then the “LO AP LIMIT” signal goes low. This signal is inverted by U14-A and goes to pin 1 of OR gate U10-A. The output of U10-A is high when either “HI AP LIMIT” or “LO AP LIMIT” is active. The signal is inverted by U14-D and goes off the circuit board to the Driver Displacement Indicator Board where it will be NANDed with two other signals to stop the oscillating piston (See DDI Theory of Operation). This signal is called “AP LIMIT” and will cause the oscillator to stop when it is driven low. The output of U14-D is also sent to OR gate U10-B. An active alarm will cause the output of this OR gate to be driven low and transistor Q5 will be turned off de-energizing the solenoid valve in the pneumatics enclosure. This will cause the pressure within the patient circuit to vent to atmosphere. The LO AP LIMIT alarm needs no reset. Once the fault has been corrected the DUMP valve will close and the oscillator will begin to run. The output of U14-D is also sent to AND gate U7-B where it is ANDed with three other signals “OSC STOPPED”, “MIN MAP” and “MAX MAP” which were discussed earlier. A low signal on any of these inputs will drive the output of U7-B low. Turning Q7 on will sound the audio alarm. AND gate U7 provides the input signal when the alarm should be active. These signals are active low. Timer U13 provides a 45 second silence triggered by a front panel switch at J1 pin 4. Power Failure Alarm When power is removed from the 3100A, relay U8 will return to its off position. Relay U9 however, will be kept in the energized state since the battery voltage on the contacts is fed back to the coil. The de-energized contacts allow the battery voltage to drive the audio alarm and the power failure light. Pressing the reset button allows Q3 to conduct breaking the circuit in the normally open U9. Comparator U12-B will generate a battery low signal when the battery voltage falls below 6.5V. Quad op-amp buffers this reference voltage to supply power to the pressure transducer. Oscillator Overheated Quad comparator U12-C and U12-D take the resistance of a Thermistor, mounted on the coil inside the oscillator, and determines if 170° C or 190° C has been reached. Signals are active lows. At 190° C a signal from U12-D will be sent to the DDI Board.
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3100A® High Frequency Oscillatory Ventilator
Driver Controller Module The Driver Controller Module generates the square wave necessary to cause the oscillations of the drive. It consists of three separate subassemblies: • Driver Controller Board • Choke Board • PWM Amplifier Driver Controller Board Integrated circuit U3 (ICL8030) is a waveform generator which will produce a sawtooth, square and triangle wave. The triangle wave at pin 3 is used to drive the controller circuitry. The negative voltage at pins 4 and 5 determine the frequency of the waveform, and a 10KΩ potentiometer mounted on the front panel, connected at P1 pins 7 and 8, determines voltage. This allows the operator to adjust between 3 and 15 Hz. Fine tuning of this frequency can be made with R18 and R19 as measured at TP8. Operational amplifier U1 supplies a signal to the front panel display meter and can be adjusted with R17. If is not necessary to make any adjustments to the potentiometers on the rear of the meter itself. Operational amplifier U2 provides offset and gain adjustments for the triangle wave with potentiometers R1 (Offset) and R2 (Gain). Test point 2 should approximate a 0 - 10V triangle waveform. This signal goes to comparator U4 (LTI011) on the negative input. The positive input is governed by the output of U2-D and the setting of a 10KΩ potentiometer mounted on the front panel labeled “% Inspiratory”. JP2 should be jumped. Do not jumper JP1. Fine tuning of the 30% and 50% Inspiratory Time limits can be made with the offset and gain potentiometers R1 and R2. A meter is connected at J22 and J23 for display. R16 adjusts the reading on the meter. The output of comparator U4 is a square wave with the selected frequency and duty cycle (% Inspiratory Time) inspirations during the high portion of the wave at TP7. There are two reference voltages created by +15V, VR1, U8-A and U8-B. These reference signals are sent to U5, a dual analog gate. The reference voltages are +5V and -5V. Each voltage goes to a separate gate on U5. The gates are enabled with a low signal. NAND gate U6-C inverts the square wave so that each gate is enabled alternately. The output of the two gates is tied together and the resultant signal is sent to the inverting input of U2-B. The signal at TP6 should be 10V P-P and centered at 0V. R4 is used as an offset adjustment and R3 is for gain. However, these adjustments are very interactive and repetitive adjustment may be necessary. The signal at TP6 should be present whenever the instrument has power applied. The signal at TP6 is then sent to a 10KΩ potentiometer used to send a variably attenuated signal to U2-C. U2-C has two possible feedback paths. When the start light is lit, the “DISABLE OSC” signal at J1 pin 6 will be at a positive voltage. Following the logic for the three NAND gates of U6, you will see that the gate of U5 will be open and the gain of U2-C will be approximately one.
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Introduction
When the gate is closed (“DISABLE OSC” high) the gain of U2-C goes to near zero. This is when the oscillator is off. The output of U2-C is the drive signal for the PWM Servo Amplifier discussed later; positive portions of the waveform move the piston forward during inspiration and negative portions of the waveform reverse the piston during expiration. U7 is an optical isolator which provides an enable signal to the PWM Servo Amplifier. Q1, CR1, C17, R40 and C18 reduce and regulate the 40V input from the Lower Power Supply Assembly to 24V. This is then sent through F1, a 500mA slow blow fuse, to power the cooling fan, the solenoid valve and the Pressure Transducer. PWM Servo Amplifier This device is used to provide a safe and reliable switching of the current needed to drive the oscillator. It is extremely efficient (97%) and is fully protected against over-voltage, overcurrent, over-heating and any shorting across the oscillator’s coil assembly. Loop gain, current limit input gain and offset can be adjusted. It receives its main drive power directly from the 60V DC power supply located in the Lower Power Supply Assembly. It also takes the drive signal and an inhibit signal from the Driver Controller Board. We do not recommend any service to this subassembly beyond adjustment and inspection of connectors. Choke Board The Choke Board is comprised of two coils which act as a high frequency choke to remove any spurious low level noise from the drive signal, which will be generated by the circuits on the PWM Servo Amplifier.
Driver Displacement Indicator Board The DDI Board has several circuits which integrate to serve the following functions: • Detect and display movement of the oscillator. • Start or stop the oscillator. Movement of the Oscillator Mounted through the rear of the driver, the DDI probe generates a current proportional to the position of the driver by sensing light from an LED also mounted on the probe. The light is modulated at approximately 8K Hz by U5 and Q3. Power is sent to both the emitter and detector in the probe via J1 pin 6. The modulated light source is reflected by the rear side of the piston inside the Driver Assembly. The reflections are sensed by the detector on the probe and translated into 8K Hz signal varying in amplitude, depending on the distance between the piston plate and the detector. This signal is buffered by U1 and demodulated by the filtering of C2, C5, C6, R13, R14, R15 and U4. Referring to the schematic, this signal splits at TP1. The top circuit is a high pass amplifier allowing only the fast changes in the resultant amplitude to be passed via C10. The bottom is a low pass amplifier using C12 as the storage capacitor. These signals are then summed by the final stage of U4. The final signal, which can be measured at each output line, activates an
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Introduction
3100A® High Frequency Oscillatory Ventilator
individual LED on the display IC’s (DS1 and DS2). Potentiometer R7 adjusts the offset or Center LED to be lit when the piston is resting in the center. R1 adjusts the gain of the low pass filter and is used to adjust the far right LED when the piston is at maximum expiration. R4 adjusts the high pass gain and determines the width of the LED display when the oscillator is oscillating. See the 4000 hour procedure for instructions when making these adjustments. There is a procedure for this in the Maintenance Section of the Operator’s Manual. Starting and Stopping the Oscillator Switch 1 is the START/STOP switch that will toggle the output of U6 and will change the output of U7. A low at U7 pin 1 will disable the oscillator via U8 and also activate the “STOP OSC ALARM DISABLE”. This signal disables the “OSCILLATOR STOPPED” alarm via the Alarm Board and is active high. The output of U8 is the “DISABLE OSC” signal which is sent to the Driver Controller Board to stop the oscillator. This pin is ACTIVE high, meaning the oscillator will be stopped if this line is high. This signal leaves the board at J1 pin 9 and is generated by any of three conditions: • The START/STOP switch is disabled. • A ∆P LIMIT alarm is active, meaning there is either a Mean Airway Pressure >50 cmH2O or <20% of that set by the “Set Max” Thumbwheel. • The OVERTEMP signal going low, meaning the driver coil is at greater than 190° C.
Driver Assembly The heart of the 3100A is the Driver Assembly. It is composed of a cylindrical permanent magnet and housing elements with a coil of wire suspended within the magnet via what we refer to as spiders. These spiders are similar to a speaker cone with much deeper convolutions to allow for greater travel. At the front of the coil a plate is mounted. This plate can be seen when the disposable Bellows/Water Trap Assembly is removed. The plate is coupled to the front housing by way of a two piece diaphragm. This diaphragm is the circular rubber ring around the piston plate. A circular piece of foam is between the two diaphragms to keep the diaphragm somewhat rigid. The 1.5 ohm driver should be reworked after every 4000 hours of use to replace the spiders and diaphragms, as they suffer fatigue over time and usage. The 3 ohm driver should be similarly reworked after every 6000 hours of use. Cooling Flow The entire cooling flow required by the Driver Assembly is approximately 40 LPM. 10-15 LPM comes directly from the cooling gas regulator PR5. An additional 25 LPM is entrained into the driver from room air through a device on the bottom side of the Driver referred to as an Air Amplifier. As the 10-15 LPM flow moves through the device, it causes a negative pressure on the bottom air port entraining the additional flow. The Driver is driven by a square wave driver referred to as the Driver Controller Module. During positive portions of the square wave, the Driver’s coil moves forward toward the patient connection and the opposite during the negative.
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A Thermistor is mounted on the coil to determine if the oscillator is overheating. The circuitry which senses the temperature is located on the Alarm Board. There are no user maintenance parts on the Driver Assembly, and all rework or repair should be performed only at a CareFusion service facility.
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3100A® High Frequency Oscillatory Ventilator
3100A HFOV
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Chapter 2
3100A® High Frequency Oscillatory Ventilator
Maintenance Procedures
Patient Circuit Calibration Procedure
The Patient Circuit Calibration Procedure describes the steps necessary to calibrate the patient circuit to the 3100A.
Ventilator Performance Checks
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3100A® High Frequency Oscillatory Ventilator
The Ventilator Performance Check assists in setting Power, Mean Pressure Adjust, and Bias flow controls to achieve specific ranges of ∆P and Paw. 3100A High Frequency Oscillatory Ventilator maintenance schedule requirements are as follows:
Scheduled Maintenance Prior to every use, perform the start up and verification procedure as outlined in the Operator’s Manual. After every use inspect and clean, if necessary, the air filter at the base of the ventilator. Four small black snaps release the cover of the filter. Every Seven Years, the Driver Power Module should be replaced. This must be performed by a factory-trained technician. Call Technical Support at 1-800-520-4368 to schedule a service call. At every 500 Hour Interval, replace the input gas filters (one for the blended gas input and one for the cooling gas input). There is a package of ten filters sent with each ventilator. Additional filters may be purchased (PART NUMBER-767163). At every 2000 Hour Interval, preventative maintenance is required. At this time, the DC power supplies, Pressure Transducer and Driver Displacement Indicator will be calibrated (See Section 1 for calibration procedures). At every 4000 Hour Interval, the 1.5 ohm Driver Assembly must be replaced with one that has been reconditioned. This must be performed by a factory trained technician. Call technical support at 1-800-520-4368 to schedule a service call. At every 8000 Hour Interval, all pneumatic components of the 1.5 ohm driver (i.e. regulators, tubing, fittings, valves, etc.) must be replaced along with the cooling fan, circuit breaker and thumbwheel switches. This maintenance must be performed by a factory trained technician. Call technical support at 1-800-520-4368 to schedule a service call. At every 6000 Hour Interval, the 3 Ohm Driver assembly must be replaced with one that has been re-conditioned. Also, select pneumatic components must be replaced. This maintenance must be performed by a factory trained technician. Call Technical Support at 1800-520-4368 to schedule a service call. At every 12000 Hour Interval, all pneumatic components of the 3 ohm driver (i.e. regulators, tubing, fittings and valves, etc.) must be replaced along with the cooling fan, circuit breaker and thumbwheel switches. This maintenance must be performed by a factory trained technician. Call Technical Support at 1-800-520-4368 to schedule service.
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Maintenance Procedures
2000 Hour Maintenance Procedure There are three functions within the Model 3100A HFOV which require calibration at 2000 hour intervals: • Control Package DC Power Supply • Airway Pressure Monitor Transducer Calibration • Piston Position and Displacement Display Maintenance of accurate calibration of these functions is extremely important to the proper function of the Model 3100A HFOV. If at any time, a calibration discrepancy exists that cannot be solved by the normal calibration procedures described below, do not attempt to treat a patient with the HFOV. Call CareFusion Technical Support immediately for assistance. The calibration interval for these functions is tracked on the Elapsed Time Meter (24) on the Rear Panel of the Control Package. A calibration must be performed at least every 2,000 hours or when a discrepancy is noticed. A National Bureau of Standards traceable digital voltmeter and a National Institute of Standards and Technology traceable pressure measurement transducer are required for proper calibration of the Power Supply and the Airway Pressure Monitor. To assure accurate setup, all periodic calibrations must be done with the Model 3100A HFOV at room temperature and prior to extensive operation of the oscillator. If the oscillator is warm due to previous operation, allow a non-operating cool-down interval of at least one hour before commencing calibration. Precaution The cover enclosing the Control Package, Column, or any other portion of the ventilator must not be removed by the user. To avoid electrical shock hazard, please refer all service requiring cover removal to a qualified biomedical equipment service technician. Control Package DC Power Supply The calibration procedure for the Control Package DC Power Supply is as follows: 1. Turn off Power to the 3100A HFOV and unplug unit from AC receptacle. 2. Remove the rear column cover. 3. Plug the 3100A HFOV back into receptacle and turn on Power. 4. Refer to Figure 2-1 and Figure 2-2 to verify which 5/15V Power Supply has been installed in the 3100A HFOV. The Power Supply is located immediately below the oscillator drive electronics.
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3100A® High Frequency Oscillatory Ventilator
Figure 2-1 Power Supply Adjustment Potentiometers.
Figure 2-2 Power Supply Adjustment Potentiometers 5. Connect the negative lead of a digital voltmeter to the +5V Com terminal of the DC Power Supply. 6. Connect the positive lead of the digital voltmeter to the +5V terminal of the DC Power Supply.
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767161 Rev. F