Service Guide
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SERVICE GUIDE
Service Guide • Aaron 940
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This Service Guide and the equipment it describes are for qualified technicians who maintain and repair the Aaron 940 High Frequency Desiccator. Additional User information is available in the Aaron 940 User’s Guide. This document covers technical descriptions of the Aaron 940 including its physical appearance, all operator controls and indications, operational specifications, component functional descriptions (module level), diagrams of the electronic circuits used, and troubleshooting guidelines (with chart comparisons). The Aaron 940 was constructed with the highest quality components. In the unlikely event that your generator fails within two years of purchase date, Bovie Medical will warranty the product and effect factory repairs. Please refer to Appendix A, Warranty for what is covered, length of coverage, and “How to Receive a Return Authorization Number.”
Equipment Covered in this Manual Aaron 940: Reference No.: A940
For Information Contact Bovie Medical • 5115 Ulmerton Road, Clearwater, FL 33760 USA U.S. Phone 1-800-537-2790 Fax 1-800-323-1640 • International Phone +1-727-384-2323 Fax +1-727-347-9144 www.boviemedical.com • [email protected] Peter J. Smith Medical Products Marketing 18 Yeates Close Thame OX9 3AR, UK Made in USA Printed in USA ©2009 Bovie Medical. All rights reserved. Contents of this publication may not be reproduced without the written permission of Bovie Medical. Bovie Part Number MC-55-190-001 Rev. 0
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SAFETY PRECAUTIONS WHEN OPERATING THE GENERATOR The safe and effective use of electrosurgery depends to a large degree on factors solely under the control of the operator. There is no substitute for a properly trained and vigilant medical staff. It is important that they read, understand, and follow the operating instructions supplied with this electrosurgical equipment. To promote the safe use of the Aaron 940, please refer to the User’s Guide for standard operating precautions.
APPLICABLE SAFETY STANDARDS CAN/CSA C22.2, NO. 601.1 - M90 UL 60601-1 (Ed. 1 Rev. 2006) Part 1 IEC 60601 - 2 - 2 (Ed. 4 Rev. 2006) Part 2-2 IEC 60601 - 1 - 2 (Ed. 4 Rev. 2001) Part 1-2 IEC 60601 - 1 (Ed. 2 Rev. 1998) Part 1 CENELEC EN 60601 - 1 (Issue 1990) Part 1
CONVENTIONS USED IN THIS GUIDE WARNING: Indicates a potentially hazardous situation which, if not avoided, could result in death or serious injury.
CAUTION: Indicates a hazardous situation which, if not avoided, may result in minor or moderate injury.
NOTICE: Indicates an operating tip, a maintenance suggestion, or a hazard that may result in product damage.
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TABLE OF CONTENTS Equipment Covered in this Manual.............................................................................ii For Information Contact ..............................................................................................ii Safety Precautions When Operating the Generator ..........................................................iii Applicable Safety Standards..............................................................................................iii Conventions Used in this Guide ........................................................................................iii The Aaron 940 .......................................................................................................................1-1 Functional Description.....................................................................................................1-2 Unit Description...............................................................................................................1-3 Safety Precautions when Repairing the Aaron 940 ........................................................1-3 General Warnings, Cautions, and Notices ..............................................................1-3 Active Accessories ..................................................................................................1-4 Fire / Explosion Hazards .........................................................................................1-4 Generator Electric Shock Hazards..........................................................................1-5 Servicing..................................................................................................................1-5 Cleaning ..................................................................................................................1-5 Controls, Indicators and Receptacles.................................................................................2-1 Front Panel......................................................................................................................2-2 Controls and Indicators Overview ...................................................................................2-3 Coagulation and Bipolar Controls ..................................................................................2-4 Accessory Receptacles...................................................................................................2-5 Front and Rear Panel Views ...........................................................................................2-6 Symbols...........................................................................................................................2-7 Technical Specifications ......................................................................................................3-1 Performance Characteristics...........................................................................................3-1 Input Power .............................................................................................................3-1 Duty Cycle ...............................................................................................................3-2 Dimensions and Weight ..........................................................................................3-2 Operating Parameters .............................................................................................3-2 Transport and Storage ............................................................................................3-2 Audio Volume ..........................................................................................................3-2 Low Frequency (50-60 Hz) Leakage Current..........................................................3-3 High Frequency (RF) Leakage Current...................................................................3-3 Standards and IEC Classifications..................................................................................3-3 Class I Equipment (IEC 60601-1) ...........................................................................3-3 Type CF Equipment (IEC 60601-1) / Defibrillator Proof..........................................3-3 Drip Proof (IEC 60601-2-2) .....................................................................................3-3 Electromagnetic Compatibility (IEC 60601-1-2 and IEC 60601-2-2) ......................3-3 EMC Compliance ....................................................................................................3-4 Output Power Characteristics .........................................................................................3-8 Maximum Output for Monopolar and Bipolar Modes ..............................................3-8 Theory Of Operation .............................................................................................................4-1 Block Diagram.................................................................................................................4-2 Functional Overview of Key Circuits ...............................................................................4-2 System Logic...................................................................................................................4-4 Aaron 940 Control Signals ..............................................................................................4-4
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Operating the Aaron 940 ......................................................................................................5-1 Inspecting the Generator and Accessories .....................................................................5-2 Service Personnel Safety................................................................................................5-2 Installation .......................................................................................................................5-3 Functional Checks...........................................................................................................5-3 Unit Operations ...............................................................................................................5-5 Maintenance...........................................................................................................................6-1 Cleaning ..........................................................................................................................6-2 Periodic Inspection..........................................................................................................6-2 Fuse Replacement ..........................................................................................................6-2 Troubleshooting ....................................................................................................................7-1 Recommended Equipment..............................................................................................7-2 Troubleshooting the Aaron 940 .......................................................................................7-4 Inspecting the Unit...................................................................................................7-2 Inspecting the Receptacles .....................................................................................7-2 Inspecting Internal Components..............................................................................7-4 Understanding Error Codes and Audio Tones.................................................................7-4 Correcting Common Problems........................................................................................7-5 Main Board Test Points ...................................................................................................7-8 Return Policy and Procedures.............................................................................................8-1 Responsibility of Manufacturer........................................................................................8-2 Returning the Unit for Service.........................................................................................8-2 Warranty ................................................................................................................................A-1 Board Drawings, Schematics, & Assemblies ....................................................................B-1 How to Order Parts from Bovie Medical .........................................................................B-2 Aaron 940 Design Breakdown and Drawing Reference.................................................B-2 Bovie Drawing and Schematic Package.........................................................................B-3
Service Guide • Aaron 940
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LIST OF FIGURES Figure 2 – 1 Figure 2 – 2 Figure 2 – 3 Figure 2 – 4 Figure 3 – 1 Figure 3 – 2 Figure 3 – 3 Figure 3 – 4 Figure 3 – 5 Figure 4 – 1 Figure 5 – 1 Figure 5 – 2 Figure 6 – 1
Layout of controls, indicators, and receptacles on the front panel..................2-2 Controls for the cut, blend, and coag modes ..................................................2-4 Location of the front panel receptacles and power switch ..............................2-5 Layout of controls and labeling on the rear and side panels ..........................2-6 Output power versus power setting for all modes...........................................3-8 Output Power versus Load • Bipolar 100% / 50% ..........................................3-8 Bipolar Mode waveform ..................................................................................3-8 Output Power versus Load • Monopolar 100% / 50% ....................................3-9 Monopolar Mode waveform.............................................................................3-9 Functional block diagram of the Aaron 940 system ........................................4-2 Installation and placement...............................................................................5-3 Unit setup ........................................................................................................5-4 Fuse.................................................................................................................6-2
SCHEMATICS AND BOARD DRAWINGS Main Board..............................................................................................................................B-3 Logic Center............................................................................................................................B-4 RF Amplifier Circuit .................................................................................................................B-5 Request Activation Sense Circuit (Hand and Foot) ................................................................B-6 Power Supply..........................................................................................................................B-7 Request Up Sense Circuit ......................................................................................................B-8 Request Down Sense Circuit..................................................................................................B-9 Power Factor Corrector Power Supply .................................................................................B-10 Power Factor Corrector Power Supply - High Voltage PFC.................................................B-11 Power Factor Corrector Power Supply - Mains Filter ...........................................................B-12 Power Factor Corrector Power Supply - Low Power SMPS ................................................B-13 Printed Circuit Board Main....................................................................................................B-14 Printed Circuit Board PFC ....................................................................................................B-15 A940 Assembly .....................................................................................................................B-16
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THE AARON 940 HIGH FREQUENCY DESICCATOR This section includes the following information: ● Functional Description ● Unit Description
● Safety Precautions When Repairing the Generator ● General Warnings, Cautions, and Notices ● Active Accessories
● Fire/Explosion Hazards
● Generator Electric Shock Hazards ● Servicing ● Cleaning
CAUTION Read all warnings, cautions, and instructions provided with this generator before using. Read the instructions, warnings, and cautions provided with electrosurgical accessories before using. Specific instructions are not included in this manual.
Service Guide • Aaron 940
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FUNCTIONAL DESCRIPTION
The Aaron 940 is a multipurpose High Frequency Desiccator for use in physician’s offices and surgi-centers. It provides unsurpassed performance, flexibility, reliability, and user convenience in one compact package. The Aaron 940 High Frequency Desiccator includes digital technology. This new technology is evident in the selfchecking circuitry and error code readouts. The unit offers monopolar and bipolar electrosurgical operations. The following are Aaron 940 key advantages and benefits. Power Capabilities Memory Self Diagnostics
Up to 40 watts of Coagulation @ 1000 Ω. Up to 40 watts of Bipolar @ 200 Ω.
The generator automatically powers up to the last power setting.
These diagnostics continually monitor the unit to ensure proper performance. Whenever they detect a problem, medical personnel receive audible and visual alarm responses, and the output is suspended until the alarm condition is cleared.
UNIT DESCRIPTION
The Aaron 940 High Frequency Desiccator is a self-contained unit, consisting of the main enclosure and power cord. The main components incorporated in the generator include: • FRONT PANEL COMPONENTS Dial for controlling power output; receptacles for connecting electrosurgical accessories; footswitch receptacle; and 7-segment display. • REAR PANEL COMPONENTS Volume control.
• OTHER COMPONENTS Power switch (located on side of unit); power cable receptacle (located on bottom of unit); connector to A901 pencil. • INTERNAL COMPONENTS Main PCB and Power Factor Corrector PCB.
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SAFETY PRECAUTIONS WHEN REPAIRING THE GENERATOR
Before servicing the Aaron 940 High Frequency Desiccator it is important that you read, understand, and follow the instructions supplied with it. Also, be familiar with any other equipment used to install, test, adjust, or repair this generator.
General Warnings, Cautions, and Notices WARNING The instrument receptacles on this generator are designed to accept only one instrument at a time. Do not attempt to connect more than one instrument at a time into a given receptacle. Doing so will cause simultaneous activation of the instruments.
CAUTIONS Do not stack equipment on top of the generator or place the generator on top of electrical equipment. These configurations are unstable and/or do not allow adequate cooling. Unit is designed to be wall mounted or mounted on a mobile stand. Provide as much distance as possible between the electrosurgical generator and other electronic equipment (such as monitors). An activated electrosurgical generator may cause electrical interference with them. Do not turn the activation tone down to an inaudible level. The activation tone alerts the surgical team when an accessory is active.
NOTICES Connect the power cord to a wall receptacle having the correct voltage. Otherwise, product damage may result.
Active Accessories WARNINGS Shock Hazard – Do not connect wet accessories to the generator. Shock Hazard – Ensure that all accessories and adapters are correctly connected and that no metal is exposed.
CAUTIONS Accessories must be connected to the proper receptacle type. In particular, bipolar accessories must be connected to the Bipolar Instrument receptacle only. Improper connection may result in inadvertent generator activation. Set power levels to the lowest setting before testing an accessory.
NOTICES To avoid incompatibility and unsafe operation, we recommend using only Aaron accessories. During bipolar electrosurgery, do not activate the generator until the forceps have made contact with the patient. Product damage may occur.
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Fire / Explosion Hazards WARNINGS Explosion Hazard – Do not install the generator in the presence of flammable anesthetics, gases, liquids, or objects. Fire Hazard – Do not place active accessories near or in contact with flammable materials (such as gauze or surgical drapes). Electrosurgical accessories that are activated or hot from use can cause a fire. Use a holster to hold electrosurgical accessories safely away from personnel and flammable materials. Fire Hazard – Do not use extension cords. Fire Hazard – For continued protection against fire hazard, replace fuses only with fuses of the same type and rating as the original fuse.
Generator Electric Shock Hazards WARNINGS Connect the generator power cord to a properly grounded receptacle. Do not use power plug adapters. Do not connect a wet power cord to the generator or to the wall receptacle. To allow stored energy to dissipate after power is disconnected (caps discharge) wait at least five minutes before replacing parts. Always turn off and unplug the generator before cleaning. Do not touch any exposed wiring or conductive surfaces while the generator is disassembled and energized. Never wear a grounding strap when working on an energized generator. When taking troubleshooting measurements use appropriate precautions such as using isolated tools and equipment, using the “one hand rule,” etc. Potentially lethal AC and DC voltages are present in the AC line circuitry, high voltage DC circuitry, and associated mounting and heat sink hardware described in this manual. These potentials are not isolated from the AC line. Take appropriate precautions when testing and troubleshooting this area of the generator. High frequency, high voltage signals that can cause severe burns are present in the RF output stage and in the associated mounting and heat sink hardware. Take appropriate precautions when testing and troubleshooting this area of the generator.
Servicing CAUTIONS Read all warnings, cautions, and instructions provided with this generator before servicing. The generator contains electrostatic-sensitive components. When repairing the generator, work at a static-control workstation. Wear a grounding strap when handling electrostatic-sensitive components, except when working on an energized generator. Handle circuit boards by their nonconductive edges. Use an anti-static container for transport of electrostatic-sensitive components and circuit boards.
Cleaning NOTICE Do not clean the generator with abrasive cleaning or disinfectant compounds, solvents, or other materials that could scratch the panels or damage the generator.
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CONTROLS, INDICATORS, AND RECEPTACLES This section describes the front, rear, and side panels, including all controls, indicators, receptacles, and ports.
Service Guide • Aaron 940
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FRONT PANEL Figure 2 – 1 Layout of controls, indicators, and receptacles on the front panel
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CONTROLS AND INDICATORS OVERVIEW Users may control most Aaron 940 functions from the front panel. Each Control is plainly marked on the front panel for quick reference. The volume control is located on the rear panel. Normal operations involve activating the generator with either a front connected handswitch or footswitch. The following components are the User Interface for the Aaron 940 High Frequency Desiccator: Power Switch
The rocker ON/OFF switch on the lower right corner. The switch turns power on and off to the unit.
Power Control Knob
This rotary knob allows you to select the desired RF power level for all modes of operation. The Power Control Knob moves at a graduated .1 watt per notch (incrementally) up to 10 watts and 1 watt per notch up from 10 to 40 watts.
Watts Display
The large power output display reports the generator’s output power setting from .1 to 40 watts.
Visual LED Indictors
The blue activation indicator reports when the unit is activated.
Audible Indicators
An activation tone sounds whenever the Aaron 940 High Frequency Desiccator is activated. The volume may be adjusted to a high or low setting. The volume adjustment is located on the rear of the unit. An alarm siren sounds during all alarm conditions. The volume of this alarm cannot be adjusted.
Service Guide • Aaron 940
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COAGULATION AND BIPOLAR CONTROLS Figure 2 – 2 Controls for the cut, blend, and coag modes
Coag and Bipolar Power Display (watts) Indicates the power set for Coag or Bipolar.
Coag and Bipolar Activation Indicator Illuminates when you activate Coag or Bipolar.
Active
Power Control
Coag and Bipolar Power Control Dial Increases or decreases the Coag or Bipolar power output.
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ACCESSORY RECEPTACLES Figure 2 – 3 Location of the front panel receptacles and power switch
Power Switch Powers the unit on or off.
Monopolar Handswitching Receptacle Accepts only Aaron handpieces.
Bipolar Receptacle Accepts only Aaron cables for bipolar handpieces.
Footswitching Receptacle Accepts only Aaron footswitch.
Handpiece Holder Securely holds Aaron handpiece when not in use.
Patient Return Electrode Receptacle Accepts only Aaron return electrode plugs designed for the A940.
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REAR AND SIDE PANEL VIEWS Figure 2 – 4 Layout of controls and labeling on the rear and side panels
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SYMBOLS ON THE FRONT, SIDE AND REAR PANELS The following table lists descriptions for symbols found on the Aaron 940 Caution: Jack location is a source of dangerous voltage.
Caution: Read directions for use prior to using equipment.
On (power: connection to the mains).
Off (power: disconnection from the mains).
Do not dispose of this device in the unsorted municipal waste stream.
Monopolar output jack (hand control pencil jack).
Bipolar output jack.
Patient Plate, for use with Monopolar modes. (optional) Footswitch jack, for foot controlled activation of monopolar (optional) and bipolar devices. Type B Equipment.
Non-ionizing radiation.
Neutral Electrode referenced to earth.
Volume control.
Explosion Risk if used with flammable anesthetics.
Fuse Enclosed.
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TECHNICAL SPECIFICATIONS All specifications are nominal and subject to change without notice. A specification referred to as “typical” is within ± 20% of a stated value at room temperature (25° C / 77° F) and a nominal input power voltage.
PERFORMANCE CHARACTERISTICS Input Power Input Voltage
100-240 VAC ~ ± 10%
Mains line frequency range (nominal):
50 – 60 Hz
Power consumption:
75 VA
Fuses (two):
1.0 A 250 VAC
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Duty Cycle Under maximum power settings and rated load conditions (Coagulation 40 W @ 1000 Ω load), the generator is suitable for activation times of 10 seconds on, 30 seconds off for one hour. NOTICE The internal temperature of the unit is constantly being monitored. If the temperature rises above 85°C an alarm sounds, the system displays an error code, and the system disables output power.
Dimensions and Weight Width
11.4 cm (4.5 in.)
Depth
11.4 cm (4.5 in.)
Height
16 cm (6.3 in.)
Weight
< 1.4 kg (< 3 lbs.)
Operating Parameters Ambient temperature range
10° to 40° C (50° to 104° F)
Relative humidity
30% to 75%, non-condensing
Atmospheric pressure
700 hPa to 1060 hPa
Warm-up time
If transported or stored at temperatures outside the operating temperature range, allow one hour for the generator to reach room temperature before use.
Transport and Storage Ambient temperature range
-34˚ to 65˚ C (-29˚ to 149˚ F)
Relative humidity
0% to 75%, condensing during transport, non-condensing during storage
Atmospheric pressure
500 hPa to 1060 hPa
Audio Volume The audio levels stated below are for the activation tone (bipolar and monopolar) and the alarm tone at a distance of one meter. Audio levels meet the requirements for IEC 60601-2-2. Activation Tone Volume (adjustable)
40 to 65 dB
Frequency
All Modes: 833 Hz
Duration
Continuous while the generator is activated
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Alarm Tone Volume (adjustable)
40 – 60 dB
Frequency
1 kHz 1⁄2 seconds / 2 kHz 1⁄2 seconds
Duration
2 seconds
Low Frequency (50-60 Hz) Leakage Current Enclosure source current, ground open
< 300 µA
Source current, patient leads, all outputs
Normal polarity, intact ground: < 10 µA Normal polarity, ground open: < 10 µA Reverse polarity, ground open: < 10 µA
Sink current at high line, all inputs
< 10 µA
High Frequency (RF) Leakage Current Bipolar RF leakage current
< 45 mA rms at 40 watts
Monopolar RF leakage current (additional tolerance)
< 150 mA rms
STANDARDS AND IEC CLASSIFICATIONS Class I Equipment (IEC 60601-1) Accessible conductive parts cannot become live in the event of a basic insulation failure because of the way in which they are connected to the protective earth conductor.
Type BF Equipment (IEC 60601-1) The Aaron 940 High Frequency Desiccator provides a high degree of protection against electric shock, particularly regarding allowable leakage currents. It is type BF equipment.
Drip Proof (IEC 60601-2-2) The generator enclosure is constructed so that liquid spillage in normal use does not wet electrical insulation or other components which, when wet, are likely to affect adversely the safety of the generator.
Electromagnetic Interference When other Aaron equipment is placed on or beneath an activated Aaron Medical High Frequency Desiccator, the Aaron 940 High Frequency Desiccator operates without interference. The generator minimizes electromagnetic interference to video equipment used in the operating room.
Electromagnetic Compatibility (IEC 60601-1-2 and IEC 60601-2-2) The Aaron 940 High Frequency Desiccator complies with the appropriate IEC 60601-1-2 and IEC 60601-2-2 specifications regarding electromagnetic compatibility.
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EMC COMPLIANCE Special precautions should be taken regarding the Aaron 940. Medical Electrical Equipment needs special precautions regarding EMC and needs to be installed and put into service according to the EMC information provided in this manual. Understand that only the Accessories supplied with or ordered from Bovie Medical should be used with your device. The use of Accessories, transducers, and cables other than those specified, may result in increased Emissions or decreased Immunity of the Aaron 940. The Aaron 940 and its accessories are not suitable for interconnection with other equipment. Portable and mobile RF communications equipment can affect Medical Electrical Equipment. The Aaron 940 should not be used adjacent to or stacked with other equipment and that if adjacent or stacked use is necessary, the Aaron 940 should be observed to verify normal operation in the configuration in which it will be used.
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Recommended separation distances between portable and mobile RF communications equipment and the Aaron 940. The Aaron 940 is intended for use in an electromagnetic environment in which radiated RF disturbances are controlled. The customer or the user of the Aaron 940 can help prevent electromagnetic interference by maintaining a minimum distance between portable and mobile RF communications equipment (transmitters) and the Aaron 940 as recommended below, according to the maximum output power of the communications equipment. Rated maximum output power of transmitter
Separation distance according to frequency of transmitter in metres (m)
W
150 kHz to 80 MHz d = 1.2 P
80 MHz to 800 MHz d = 1.2 P
800 MHz to 2.5 GHz d = 2.3 P
0.01
0.12
0.12
0.23
0.1
0.38
0.38
0.73
1
1.2
1.2
2.3
10
3.8
3.8
7.3
100
12
12
23
For transmitters rated at a maximum output power not listed above, the recommended separation distance d in metres (m) can be estimated using the equation applicable to the frequency of the transmitter, where P is the maximum output power rating of the transmitter in watts (W) according to the transmitter manufacturer. NOTE 1 At 80 MHz and 800 MHz, the separation distance for the higher frequency range applies. NOTE 2 These guidelines may not apply in all situations. Electromagnetic propagation is affected by absorption and reflection from structures, objects and people.
Guidance and manufacturer’s declaration – electromagnetic emissions The Aaron 940 is intended for use in the electromagnetic environment listed below. The customer or the user of the Aaron 940 should assure that is is used in such an environment. Emissions test
Compliance
RF Emissions CISPR 11
Group 2
RF Emissions CISPR 11
Class A
Harmonic emissions IEC 61000-3-2
Class A
Voltage fluctuations/flicker emissions IEC 61000-3-3
Complies
Service Guide • Aaron 940
Electromagnetic environment - guidance
The Aaron 940 must emit electromagnetic energy in order to perform its intended function. Nearby electronic equipment may be affected. The Aaron 940 is suitable for use in all establishments other than domestic and those directly connected to the public low-voltage power supply network that supplies buildings used in domestic purposes.
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Guidance and manufacturer’s declaration – electromagnetic immunity The Aaron 940 is intended for use in the electromagnetic environment listed below. The customer or the user of the Aaron 940 should assure that it is used in such an environment. Immunity test
IEC 60601 test level
Compliance level
Electrostatic discharge (ESD) IEC 61000-4-2
±6 kV contact ±8 kV air
±6 kV contact ±8 kV air
Electrical fast transient/burst IEC 61000-4-4
±2 kV for power supply lines ±1 kV for input/output lines
±2 kV for power supply lines
Surge IEC 61000-4-5
±1 kV differential mode ±2 kV common mode
±1 kV differential mode ±2 kV common
Not Applicable
Electromagnetic environment - guidance
Floors should be wood, concrete or ceramic tile. If floors are covered with synthetic material, the relative humidity should be at least 30%. Mains power quality should be that of a typical commercial or hospital environment. Mains power quality should be that of a typical commercial or hospital environment.
<5 % Ut <5 % Ut (>95 % dip in Ut ) (>95 % dip in Ut ) for 0.5 cycle for 0.5 cycle
Mains power quality should be that of a typical commercial or hospital 40 % Ut Voltage dips, short (60 % dip in Ut ) for environment. If the user of the interruptions and voltage Aaron 940 requires continued 5 cycles variations on power supply operation during power mains 70 % Ut 70 % Ut input lines interruptions, it is recommended (30 % dip in Ut ) (30 % dip in Ut ) for that the Aaron 940 be powered IEC 61000-4-11 25 cycles from an uninterruptible power supfor 25 cycles ply or a battery. <5 % Ut <5 % Ut (>95 % dip in Ut ) (>95 % dip in Ut ) for 5 sec for 5 sec 40 % Ut (60 % dip in Ut ) for 5 cycles
Power frequency (50/60 Hz) magnetic field IEC 61000-4-8
3 A/m
3 A/m
Power frequency magnetic fields should be at levels characteristic of a typical location in a typical commercial or hospital environment.
NOTE Ut is the a.c. mains voltage prior to application of the test level.
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Guidance and manufacturer’s declaration – electromagnetic immunity continued... Immunity test
Conducted RF IEC 61000-4-6
IEC 60601 test level
3 Vrms 150 kHz to 80 MHz
Compliance level
3 Vrms (V1)
Electromagnetic environment - guidance
Portable and mobile RF communications equipment should be used no closer to any part of the Aaron 940, including cables, than the recommended separation distance calculated from the equation applicable to the frequency of the transmitter. Recommended separation distance d = [ 3.5] P 3
d = [ 3.5] P 3
80 MHz to 800 MHz
d = [7
3
Radiated RF IEC 61000-4-3
3 V/m 80 MHz to 2.5 GHz
3 V/m (E1)
]
P
800 MHz to 2.5 GHz where P is the maximum output power rating of the transmitter in watts (W) according to the transmitter manufacturer and d is the recommended separation distance in metres (m) Field strengths from fixed RF transmitters, as determined by an electromegnetic site survey,a should be less than the compliance level in each frequency range.b Interference may occur in the vicinity of equipment marked with the following symbol.
NOTE 1 At 80 MHz and 800 MHz, the separation distance for the higher frequency range applies. NOTE 2 These guidelines may not apply in all situations. Electromagnetic propagation is affected by absorption and reflection from structures, objects and people. a
Field strengths from fixed transmitters, such as base stations for radio (cellular/cordless) telephones and land mobile radios, amateur radio, AM and FM radio broadcast and TV broadcast cannot be predicated theoretically with accuracy. To assess the electromagnetic environment due to fixed RF transmitters, an electromagnetic site survey should be considered. If the measured field strength in the location which the Aaron 940 is used exceeds the applicable RF compliance level above, the Aaron 940 should be observed to verify normal operation. If abnormal performance is observed, additional measures may be necessary, such as reorienting or relocating the Aaron 940.
b
Over the frequency range 150 kHz to 80 MHz, field strengths should be less than [3] V/m.
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OUTPUT POWER CHARACTERISTICS Maximum Output for Bipolar and Monopolar Power readouts agree with actual power into rated load to within 20% or 5 watts, whichever is greater. Mode
Output Power
Output Frequency
Repetition Rate
Vp-p max
Coagulation
40 W @ 1000 Ω
550 kHz ± 50 kHz
21 kHz ± 10%
8.0 kV
Bipolar
40 W @ 200 Ω
550 kHz ± 50 kHz
21 kHz ± 10%
2.5 kV
* an indication of a waveform’s ability to coagulate bleeders without a cutting effect Figure 3–1 illustrates output power delivered to rated load for all available modes. Figures 3–2 and 3–4 illustrates the maximum peak voltage available at a given power setting and output mode. Figures 3–3 and 3–5 are the output waveforms as viewed on an oscilloscope. Figure 3–1
Output power versus power setting for all modes
Figure 3–2
Output Power versus Load • Bipolar 100% / 50%
Figure 3–3
Bipolar Mode Waveform
Bipolar
100% 50%
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Figure 3–4
Output Power versus Load • Monopolar 100% / 50%
Figure 3–5
Monopolar Mode Waveform
Monopolar 100%
50%
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THEORY OF OPERATION This section includes the following information: ● Block diagram
● Functional overview of key circuits ● System logic
● Aaron 940 control signal inputs and outputs.
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BLOCK DIAGRAM Figure 4-1 Functional block diagram of the Aaron 940 system
FUNCTIONAL OVERVIEW OF KEY CIRCUITS
The following descriptions highlight the main circuits in the Aaron 940 High Frequency Desiccator.
Power Factor Corrector
The unit incorporates a PFC Circuit to generate the regulated high voltage for the RF output power. The nominal DC voltage from the high voltage power supply is +72.5 ± 2.5VDC. The PFC also generates the low voltage (+90 ± 10%) to power the low voltage DC power supplies.
Low Voltage DC Supplies
The unit incorporates two regulated low voltage levels to control generator operations. They are: 8 VDC and 5 VDC. • The 8 VDC circuit supplies power for the request sense circuits, the audio circuit, and the RF drive circuit. This circuit turns on and off the power MOSFETS for the RF output power. • The 5 VDC circuit supplies power for the logic system, and all of the displays and indicators.
High Voltage Sensing
The unit incorporates a sensor to continually moitor the Regulate High Voltage. If this voltage is not within limits, the system displays Error Code E2 and disables the RF output.
Temperature Sensing Circuit
The temperature sensing circuit is used by the system logic to monitor the internal temperature of the unit. If the temperature rises above 85° C, the system displays an error code and disables the RF output. 4-2
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Request Activation Up/Down Sensing Circuits
The Activation Up/Down Request Sensing Circuits are used by the system logic to detect both hand controlled activation and foot-controlled activation and up/down requests. This circuit is made up of a colpitts oscillator (operating at approximately 50 kHz) and a level detection circuit power.
In a non-activation status, the colpitts oscillator operates at its set operating frequency, and presents a sine wave to the up/down level detection circuit. The level detection circuit converts the sine wave into a square wave. Activation will not occur as long as a square wave is present. When a resistance (approximately 200 Ω or less) is presented to the transformer’s secondary winding by a handcontrol or foot-control, the sense transformer is essentially shorted. The “short” is felt on the transformer’s primary winding causing the colpitts oscillator to temporarily shut down. When the oscillator shuts down, the sense signal becomes +5 VDC (logic “1”). This informs the system logic that a handswitch or footswitch activation request has been made.
If the square wave (from any of the request sense circuits) is not present at the system logic when the unit is initially turned on, an error code is displayed, an alarm sounds, and the RF output is disabled.
Speaker Circuit
The audio circuit is used by the system logic to generate activation tones and alarm tones. Volume for the activation tones may be adjusted from the back panel of the unit. NOTICE Alarm volume cannot be adjusted up or down.
RF Amplifier Circuit
The RF Amplifier Circuit generates the RF output energy that is delivered to the patient. It is a single-ended power amplifier incorporating two power MOSFET, and a step-up transformers.
The initial RF drive pulse is generated by the Digital PWM circuit and the system logic unit. When the RF drive pulse turns the power MOSFET “ON,” current flows from the high voltage supply through the output transformers, through the clamping diodes, and then through the MOSFET to high voltage ground. The energy developed by the “ON” time is stored in an LC tank circuit. When the MOSFET are OFF the energy is delivered to the patient through the output capacitors. A longer “ON” time develops more energy in the LC tank circuit; therefore, more energy is delivered to the patient.
Controls and Indicators
The Aaron 940 controls and indicators are listed below:
• DISPLAYS Seven segment displays indicate the output power in watts.
• ACTIVATION INDICATOR Blue LED indicates that the generator is activated.
• POWER CONTROL KNOB These mechanical encoder adjust the output power for each mode. • POWER SWITCH A double pole single throw switch that snaps into the housing. This switch supplies the AC mains current to the generator.
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Digital PWM Circuit
The Digital Pulse Width Modulation (PWM) Circuit controls the output power of the unit. This digitally controlled signal is used by the system logic to provide a precise signal to the RF drive. The pulse width is determined by power setting (generated by the user) on the front of the unit.
When a power is selected, the system logic determines what the pulse width needs to be to deliver the requested output.
SYSTEM LOGIC
The control logic uses a Field Programmable Gate Array as the “brain” of the Aaron 940 High Frequency Desiccator. This system interprets all of the inputs and delivers the correct corresponding outputs. Every operation of the unit is controlled from this system.
A System Clock Circuit, composed of an oscillator, provides the basic operating frequency of 5 MHz.
The Reset Circuit provides a single pulse at the time the Aaron 940 High Frequency Desiccator is turned on. This pulse resets Field Programmable Gate Array to ensure proper operation.
AARON 940 CONTROL SIGNAL INPUTS AND OUTPUTS
The following table lists the important input and output signals. From a troubleshooting standpoint, the absence (and presence) of these signals will help you isolate problems. Signal Name
Description
INDICATOR
These are signals from the system logic that illuminates the activation LED indicator.
AUD_VOL
ENCDR1_REQ ENCDR2_REQ CALIBRATE
TEST_MODE SPKR_DRV1 SPKR_DRV2 RF_DRV TEMP_SEN
This is the input signal to the control logic to change the audio volume.
These are output signals from the encoder to control the power setting of the system. RESERVED RESERVED
These are signals from the system logic that generates the activation tone and alarm tones. These signals are used by the audio circuit.
This is an output signal from the digital PWM circuit that controls the pulse width duration for the RF drive.
This is an input signal from the Temperature Sense Circuit that informs the system logic if the internal temperature of the unit is above 85° C. If the internal temperature of the unit is below 85° C a logic 1 (5 VDC) is sent to the system logic. If the internal temperature of the unit rises above 85° C a logic 0 (0 VDC) is sent to the system logic.
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Signal Name HV_SNS
Description
This is an input signal from the high voltage sense circuit that informs the system logic if a high voltage error has occurred. If the line voltage is within normal operating parameters a logic 1 (5 VDC) is sent to the system logic.
ACT_REQ
UP_REQ
DWN_REQ
If the line voltage increase by more than 30% a logic 0 (0 VDC) is sent to the system logic.
This is an input signal from the activation sense circuit. This signal is generated by a colpitts oscillator. When an activation request is made, this oscillator become a logic 1 (5 VDC) signal.
This is an input signal from the UP request sense circuit. This signal is generated by a colpitts oscillator. When an activation request is made, this oscillator becomes a logic 1 (5 VDC) signal.
This is an input signal from the down sense circuit. This signal is generated by a colpitts oscillator. When an activation request is made, this oscillator becomes a logic 1 (5 VDC) signal.
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OPERATING THE AARON 940 This section covers the following topics:
● Inspecting the generator and accessories ● Service personnel safety
● Installation and placement
● Functional (operational) checks
● How to set up and start the unit.
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INSPECTING THE GENERATOR AND ACCESSORIES
Before each use of the Aaron 940 High Frequency Desiccator, inspect the unit and all accessories to verify good working order: • Inspect for physical damage to the High Frequency Desiccator and its connections. • Verify that the appropriate accessories and adapters are present.
• Inspect all cords and connectors for signs of wear, damage, and abrasion. • Verify that no error messages are displayed when the unit is turned on.
SERVICE PERSONNEL SAFETY WARNINGS Hazardous Electrical Output – This equipment is for operational use only by a trained, licensed, physician. Bio-Med Technicians must also exercise caution when testing or repairing a unit. Electric Shock Hazard – Connect the generator power cord to a properly grounded receptacle. Do not use power plug adapters. Connect the power cord to a properly polarized and grounded power source with the frequency and voltage characteristics that match those listed on the back of the unit. Fire Hazard – Do not use extension cords.
CAUTION Do not stack equipment on top of the generator or place the generator on top of electrical equipment. These configurations are unstable and / or do not allow for adequate cooling. Provide as much distance as possible between the High Frequency Desiccator and other electronic equipment (such as monitors). An activated High Frequency Desiccator may cause interference with them. Nonfunction of the generator may cause interruption of surgery. A backup electrosurgical generator should be available for use. Do not turn the activation tone down to an inaudible level. This activation tone alerts the surgical team when an accessory (and the generator) is active. When using a smoke evacuator in conjunction with the High Frequency Desiccator, place the smoke evacuator a distance away from the generator. Set the generator’s volume control (on the rear panel) at a level that ensures all activation tones may be heard.
NOTICE Connect the power cord to a wall outlet having the correct voltage. Otherwise product damage may result.
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INSTALLATION AND PLACEMENT
Mount the Aaron High Frequency Desiccator on the wall or optional mobile stand using the standard mounting kit (see figure 5-1). Do not operate the unit in the horizontal position, as liquids may spill into unit. Ensure that air flows freely on all sides of the unit.
WARNING Connect the power cord to a properly polarized and grounded power source with the frequency and voltage characteristics that match those listed on the back of the unit.
Figure 5-1 Installation and placement
FUNCTIONAL (OPERATIONAL) CHECKS
Upon initial installation of the unit, perform the following checks. Refer to the figures in Controls and Indicators for the location of connectors and generator controls. WARNING At no time should you touch the active electrode or bipolar forceps. A serious burn could result.
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How to Set Up and Start the Aaron 940 Unit
Figure 5-2 Unit setup
1. Verify that the Power Switch is in the OFF position and that no accessories are connected to the unit.
2. Connect a hospital-grade power cable to the AC power cable receptacle on the back of the unit, then to a properly grounded wall outlet (see figure 5-2, letter A).
3. Plug the handpiece into the monopolar output on the lower left of the front on the unit (see figure 2, letter B). The plug is designed to fit in only one direction. Plug the smaller round connector from the handpiece into the receptacle on the bottom of the unit (see figure 2, letter B). The three button handpiece is designed to give the doctor complete fingertip control of the power output settings. 4. Slide the standard electrode into the handpiece until it is firmly seated (see figure 5-2, letter C). The handpiece will accept most standard 3/32" electrodes. 5. Slide the handpiece from above into the holder on the right side of the unit.
6. Turn the unit power on utilizing the switch on the right side panel of the unit (see figure 5-2, letter D).
7. Set the power output either by using the dial on the front of the unit (see figure 2, letter E) or by the up and down buttons on the handpiece (see figure 2, letter J). When power level adjustment is being made by the handpiece an audible tone will sound to indicate that the power level has been changed. Depressing and holding the up or down buttons will cause the power settings to change more rapidly for quick adjustment of the output settings. Power output is displayed in “.1” watt increments below 10 watts and in whole numbers from 10 to 40 watts. NOTICE: The output settings can not be adjusted when the unit is being activated.
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How to check the unit operation with a Footswitch
1. Connect a footswitch to the footswitch jack on the front of the unit. 2. Set the power setting to 0.1 watts.
3. Verify that the Activation LED illuminates blue, and that the system generates the Activation tone when you press the pedal on the footswitch. 4. Confirm that releasing the footswitch pedal returns the unit to an idle state.
How to Check the Monopolar Mode
1. Connect the monopolar handpiece to the Monopolar receptacle. 2. Set the power setting to 0.1 watts.
3. Verify that the generator activates when the button on the handpiece is depressed.
UNIT OPERATION
The Aaron 940 High Frequency Desiccator produces radio frequency current which is useful for the removal and destruction of superficial cutaneous and mucosal lesions. This is done by performing desiccation and fulguration procedures. Electrosurgical desiccation occurs when the electrode is placed directly onto the surface of the lesion. Fulguration occurs when the electrode is held slightly above the lesion and an arc is delivered to the lesion. The unit also provides fast and efficient bleeding control by coagulation of capillaries and small blood vessels.
For the majority of desiccation, fulguration, and coagulation procedures utilizing the standard handpiece in the monopolar output, the patient plate is optional. When used, the patient plate will intensify the coagulation properties of the unit and also lessen the opportunity for an electrosurgical burn. The optional footswitch adds versatility when using the standard handpiece in the monopolar output, as the footswitch allows you to activate the unit by either the handpiece or the footswitch. Bipolar outputs are available for those physicians who prefer to utilize bipolar forceps to perform coagulation procedures. A footswitch is required when using the bipolar output. Procedures that are performed in sensitive areas may require an anesthetic. Flammable anesthetics should not be used. If you are unfamiliar with the operation of a low powered electrosurgery unit, it is advisable to practice on chicken or lean flank steak to visualize the effects at various output and power levels.
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MAINTENANCE This section includes the following information: ● Cleaning the unit ● Performing periodic inspection
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Bovie Medical recommends that you complete periodic inspection and performance testing. Perform inspections and performance testing every six months. A qualified biomedical technician should conduct this testing to ensure that the unit is operating effectively and safely.
CLEANING After each use, clean the unit. WARNING: Electric Shock Hazard - Always turn off and unplug the generator before cleaning.
NOTICE: Do not clean the generator with abrasive cleaning or disinfectant compounds, solvents, or other materials that could scratch the panels or damage the generator.
1. Turn off the generator, and unplug the power cord from the wall outlet. 2. Thoroughly wipe all surfaces of the generator and power cord with a mild cleaning solution or disinfectant and a damp cloth. Follow the procedures approved by your institution or use a validated infection control procedure. Do not allow fluids to enter the chassis. Do not sterilize the generator.
PERIODIC INSPECTION Every six months, visually inspect the Aaron 940 for signs of wear or damage. In particular, look for any of the following problems: • Damage to the power cord • Damage to the power cable receptacle • Obvious damage to the unit • Damage to any receptacle • Accumulation of lint or debris in or around the unit.
FUSE REPLACEMENT Fuses for the unit reside directly below the Power Cable Receptacle on the rear of the unit. To replace the fuses, follow this procedure: 1. Unplug the power cord from the wall outlet. 2. Remove the power cord from the Power Cable Receptacle on the rear panel. 3. To release the fuse drawer, insert a small flathead screwdriver into the slot on the drawer below the power cord receptacle. Then, slide the drawer out. 4. Remove the two fuses and replace them with 1.0 A 250V Slow Blow fuses. 5. Insert the fuse holder into the Power Cable Receptacle. NOTICE: If the unit does not display an error and does not power on, check fuses.
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Figure 6-1 Fuse
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TROUBLESHOOTING This section includes error code descriptions and actions to take to resolve them.
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RECOMMENDED EQUIPMENT FOR TROUBLESHOOTING
The following equipment enables you to troubleshoot and repair the Aaron 940 High Frequency Desiccator. • Digital multimeter with leads • Electrosurgical analyzer or a true RMS voltmeter such as a Fluke 8920A • Wideband current transformer such as a Pearson 4100 • Non-inductive RF load resistors 200 ohms, 1000 ohms • Oscilloscope (dual channel) at 100 MHz • Oscilloscope probes, (2) 10X and 1000X • Bovie/Aaron footswitch • Bovie/Aaron handswitching pencil (single use or reusable) • Standard technician’s tool kit • Miscellaneous test leads and cables.
TROUBLESHOOTING THE AARON 940
If the generator is not functioning properly, use the information in this section to perform the following activities: • Identify and correct the malfunction. • If an error code was displayed, take the appropriate action(s) to correct the error condition.
Inspecting the Generator
If the Aaron 940 malfunctions, check for obvious conditions that may have caused the problem. 1. Check the generator for visible signs of physical damage. 2. Verify that all accessory cords are properly connected.
3. Check the power cord. Replace the power cord if you find exposed wires, cracks, frayed insulation, or a damaged connector. 4. Remove the back panel and inspect all internal connections. 5. Verify that the fuses are firmly seated and are not blown.
6. You may need to replace the fuses if the generator fails to start up. Refer to Fuse Replacement in Section 6.
Inspecting the Receptacles Equipment required: • Footswitch • Bipolar cable • Monopolar instrument • Return electrode cable Procedure: 1.
Turn off the generator.
2.
Disconnect the power cord from the wall receptacle.
4.
Check for a secure fit by inserting the footswitch connector into footswitch receptacle. If the footswitch receptacle is damaged, replace the footswitch connector.
3.
5.
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Check the footswitch receptacle on the front of the unit for obvious signs of obstruction and damage.
Check the Bipolar receptacle on the front of the unit for obstruction or damage.
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6. 7.
Insert a bipolar cable into the bipolar receptacle on the front of the unit. Verify a secure fit. If the Bipolar receptacle is damaged, replace the bipolar jacks.
Check the monopolar handpiece receptacle on the front of the unit for obstruction or damage.
8. Insert a monopolar handpiece into the monopolar handpiece receptacle on the front of the unit. Verify a secure fit. If the monopolar handpiece receptacle is damaged, replace the monopolar jacks.
Inspecting Internal Components CAUTION The generator contains electrostatic-sensitive (ESS) components. When repairing the generator, work at a static-control workstation. Wear a grounding strap when handling electrostatic-sensitive components. Handle circuit boards by their nonconductive edges. Use an anti-static container for transport of electrostatic-sensitive components and circuit boards.
To inspect the internal components, follow this procedure:
1. Remove the four screws that secure the back panel to the unit. 2. Lift the back off the chassis.
3. Visually inspect and verify that all connectors are firmly seated.
4. Inspect the board for damaged components, wires, cracks and corrosion.
5. Reinstall the back panel by positioning the panel over the enclosure, and securing the four screws.
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UNDERSTANDING ERROR CODES AND AUDIO TONES
The Aaron 940 High Frequency Desiccator includes automatic, perpetual self-diagnostics. If the diagnostics detect an error, the system displays an error code, sounds an audible tone, and deactivates the output power. Any errors detected will shut down the RF output power.
NOTICE Internal firmware self-diagnostics continually monitor the unit’s operation to ensure proper and safe performance.
Most error codes result from faults in accessories attached to the unit. The following table lists the error codes, describes the error, and recommends actions to take to resolve the error.
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CORRECTING COMMON PROBLEMS
If a solution is not readily apparent, use the table below to help identify and correct specific malfunctions. After you correct the malfunction, verify that the generator successfully completes the self-test. Situation
Possible cause
Generator does not respond when turned on.
Disconnected power cord, faulty wall receptacle, or faulty power cord
Recommended action 1. 2.
PFC board malfunction Fuses blown
Generator is on, but will not activate.
Activation and / or alarm tones do not sound; speaker is malfunctioning.
Check power cord connections (generator and wall receptacle). Connect the power cord to a functional wall receptacle. If necessary, replace the power cord. Replace the PFC board.
1. 2.
Check fuses. If necessary, replace fuse(s). If a problem persists, use a backup generator.
Loose or disconnected internal cables
Check all internal connections.
Faulty power switch
Replace the power switch.
An alarm condition exists.
Check the display for an error code. Note the number and refer to Error Code list.
Loose or disconnected internal cables
Check and correct all internal connections.
Faulty power switch
Replace the power switch.
Main board malfunction
Replace the main board.
Loose or disconnected cable between main board and back panel
Check / connect all connections from the speaker board to the main board.
Main board malfunction
Check / connect cable from the main board to the back panel. Replace the main board.
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Situation
Possible cause
Recommended action
Blank or confusing LED display
Loose or disconnected internal cables
Check and correct all internal connections.
Main board malfunction
Replace the main board.
Generator is on and the accessory is activated, but generator does not deliver output.
Malfunctioning footswitch or handswitching instrument
1. 2. 3.
Power set too low An error condition exists
Increase the power setting. 1. 2.
Replace the main board.
PFC board malfunction
Replace the PFC board. 1. 2. 3.
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Check the display for an error code number. Note the number and refer to the error codes descriptions in this section.
Main board malfunction
RF output stage malfunction
Footswitch will not activate output.
Turn off the generator. Check and correct all accessory connections. Turn on the generator. Replace the accessory if it continues to malfunction.
Troubleshoot the RF output stage as described below: On the main board, verify output pulses (TP1) during activation. If pulses are not present replace the Main board. Check the power MOSFETs for failure (typically fail as shorted).
Loose or disconnected internal cables
Check and correct all internal connections.
Malfunctioning or damaged footswitch receptacle
Replace the Footswitch connector assembly.
Footswitch activation signal lost on main board
Replace the main board.
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Situation
Possible cause
Pacemaker interference
Intermittent connections or metal-tometal sparking
Recommended action 1. 2.
Current traveling from active to return 1. electrode during monopolar Electrosurgery is passing too close to pacemaker. 2.
3.
4. 5.
Abnormal neuromuscular stimulation (stop surgery immediately)
Ser vice Guide • Aaron 940
Check all connections to the generator. It may be necessary to re-program the pacemaker. Use bipolar instruments, if possible. If you must use a monopolar instrument, place the patient return electrode as close as possible to the surgical site. Make sure the current path from the surgical site to the patient return electrode does not pass through the vicinity of the heart or the site where the pacemaker is implanted. Always monitor patients with pacemakers during surgery and keep a defibrillator available. Consult the pacemaker manufacturer or hospital. Contact the Cardiology Department for further information when use of electrosurgical appliances is planned on patients with cardiac pacemakers.
Metal-to-metal sparking
Check all connections to the generator, patient return electrode, and active electrodes.
Can occur during coag
Use a lower power setting for Coag.
Abnormal 50 Hz - 60 Hz leakage currents
Inside the generator, carefully inspect for damage that may cause shorting between the AC line voltage and connected patient components.
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MAIN BOARD TEST POINTS Test Point
Description
TP1 (RFDRIVE)
RF DRIVE SIGNAL
TP2 (+HV)
HIGH VOLTAGE POWER SUPPLY
TP3 (HVGND)
HIGH VOLTAGE GROUND
TP4 (+8 VDC)
8 VOLT DC POWER SUPPLY
TP5 (+5 VDC)
5 VOLT DC POWER SUPPLY
TSTPNT
LOW VOLTAGE GROUND
POWER FACTOR CORRECTOR BOARD TEST POINTS Test Point
Description
TP1 (+70 VDC)
+70V DC FOR RF OUTPUT STAGE
TP2
PRIMARY XFMR T1
TP3
GND_PFC
TP4
GND_PFC
TP5
SECONDARY XFMR T2
TP6
PRIMARY XFMR T2
TP7
GND_PRI_LPS
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