Cosman G4 User manual

DATE
11/7/2008 STANDARD PROCEDURE INSTRUCTIONS
SPI #
11291
REV.
A
SUPERSEDES
N/A COSMAN MEDICAL, INC
PAGE 1 of 115
DO NOT ISSUE REV
SHEET
G4 Service Manual
ECO # REVISION DESCRIPTION
Eng. Draft 1 Version for initial product release.
Prepared by:____________________________ Date: ____________
Approved by: ___________________________ Date: ____________
Manufacturing
Approved by: ___________________________ Date: ____________
Engineering
Approved by: ___________________________ Date: ____________
Quality and Regulatory Affairs
Approved by: ___________________________ Date: ____________
Management

Cosman G4 Radiofrequency Generator Service Manual (SPI 11291 Rev A)
Section 1

Cosman G4 Radiofrequency Generator Service Manual (SPI 11291 Rev A)
Cosman G4
Radiofrequency Generator
Service Manual
Section 1

Cosman G4 Radiofrequency Generator Service Manual (SPI 11291 Rev A)
Title and Publication Number
G4 Service Manual
SPI 11291 Rev. A
Copyright Information
© 2008 by Cosman Medical, Inc., Burlington, Massachusetts, USA.
All rights reserved.
Caution
U.S. Federal law restricts this device to sale by, or on the order of, a physician licensed by the state in which he practices to
use, or order the use of, the device.
Limited Warranty
Cosman Medical, Inc. warrants to the original purchaser that the equipment listed in the Operators’ Manual shall be free from
defects in material and workmanship for a period of 1 year from the date of shipment. Cosman Medical, Inc. obligation under
this warranty shall be limited to repair or replacement, at the option of Cosman Medical, Inc. The above warranty is
contingent upon normal usage and does not cover products that have been modified without Cosman Medical’s approval or
which have been subjected to unusual physical or electrical stress.
Electrodes: Since electrodes are more subject to abuse, the warranty differs from the G4 Generator.
Notices
No part of this document may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means—
electronic, mechanical, photocopying, recording, or otherwise—without the expressed, written consent of Cosman Medical,
Inc. Additional copies of this document can be ordered from Cosman Medical.
Trademarks
G4, Graphics 4, Graphics Four, and RFG-4 are trademarks of Cosman Medical, Inc. All trade names referenced are the
trademarks, registered trademarks, or products of their respective manufacturers.
Manufactured By
Cosman Medical, Inc.
76 Cambridge St.
Burlington MA 01803 USA
Tel: [phone]
Fax: [phone]
Section 1
EC REP
Neurotechnics Ltd.
8 Manor Park
Banbury OX16 3TB
United Kingdom
Internet Address
www.cosmanmedical.com
FCC Statement Concerning RFI
The G4 generates and uses radio-frequencies. The equipment may cause interference with other medical equipment in the
vicinity. If interference occurs, one or more of the following measures could remedy the problem:
• Move the G4 away from the affected equipment.
• Plug the G4 into a separate outlet so that it is on a different branch circuit.
If necessary, consult the manufacturer of the affected equipment or an experienced technician. In addition, the booklet “How
to Identify and Resolve Radio-TV Interference Problems” may be helpful. This booklet is published by the FCC and is
available from the U.S. Government Printing Office, Washington, D.C., 20402, Stock No. 004-00-00345-4.

Cosman G4 Radiofrequency Generator Service Manual (SPI 11291 Rev A)
Sections
1. General Information
1.1 Device Classification
1.2 Electrical Safety and EMC
1.3 Electrical Safety Information
1.4 Key to Device Markings
2. Chassis Layout
2.1 Front Panel Layout
2.2 Back Panel Layout
3. Getting Started
3.1 Description
3.2 Indications for Use
3.3 Unpacking the G4 System
4. Turning on the G4 & Main Menu
5. System Setup
5.1 Date, Time, Language, and Audio Volume
5.2 Touch Screen Calibration
5.3 Testing the G4 Unit
5.4 Error and Warning Dialogs
6. Start Procedure Screen
7. Electrode Setup Screen
7.1 Electrode Setup Settings
8. Graphing Interface
8.1 Stimulation Screen
8.2 Thermal RF Screen
8.3 Pulsed RF Screen
9. One Touch Interface
9.1 Stimulation Screen
9.2 Thermal RF Screen
10. Sterilization, Care, and Service
11. Troubleshooting
12. Specifications
13. Output Power Curves
14. Accessories
15. Test Equipment
16. System Testing
16.1 Application Program check
16.2 Low voltage Oscillator resonance check
16.3 Touch Screen Display test
16.4 Temperature Display calibration check
16.5 High volts measurement calibration
16.6 Peak voltage display calibration
16.7 Off zero lockout test
16.8 Display checks
16.9 Lesion timer test
16.10 Automatic temperature control
16.11 Temperature Variation with cables
16.12 Impedance Variation with cables
16.13 Impedance range tests
16.14 No Temp lock-out test
16.15 Audio calibration adjustment
16.16 Stimulator tests
16.17 Maximum RF output test
17. Electrical Safety Tests
17.1 HIPOT Testing
17.2 Leakage Testing
17.3 Ground Bond Test
18. Final check out
19. System Diagram
20. Schematic Drawings
20.1 Backplane Board Assembly
20.2 RMS Stim Board Assembly
20.3 Current Board Assembly
20.4 USB Card Board Assembly
20.5 Power Supply Board Assembly
21. PC Board Assemblies
21.1 Backplane Board Assembly
21.2 RMS Stim Board Assembly
21.3 Current Board Assembly
21.4 USB Card Board Assembly
21.5 Power Supply Board Assembly
22. Part lists
22.1 Backplane Board Assembly
22.2 RMS Stim Board Assembly
22.3 Current Board Assembly
22.4 USB Card Board Assembly
22.5 Power Supply Board Assembly
23. Data sheet
Section 1

Cosman G4 Radiofrequency Generator Service Manual (SPI 11291 Rev A)
Section 1
1. General Information
Safe and effective RF lesioning is dependent not only on equipment design, but also on factors under
control of the operator. Do not attempt to operate the G4 prior to completely reading and
understanding the instructions for use.
WARNING: Electric Shock Hazard
There are no user serviceable parts inside the G4. To avoid
electric shock, return the device to Cosman for servicing.
WARNING: Hazardous Electrical Equipment & Active Implants
This equipment is intended for use by qualified personnel only.
This equipment may damage or interfere with the operation of cardiac
pacemakers and other active implants.
Do not use within 15 feet (4 meters) of a cardiac pacemaker unless proper
cautions have been taken. Before use of the Generator, contact the
pacemaker company to determine whether the pacemaker needs to be
converted to fixed rate pacing during the radiofrequency procedure. When
the pacemaker is in the sensing mode, it may interpret the RF signal as a
heartbeat and may fail to pace the heart.
This equipment has an output which is capable of causing a
physiological effect.
WARNING: Risk of Burns and Fire.
Do not use near conductive materials such as metal bed parts or inner
spring mattresses.
WARNING: Protective Earth Grounding
Grounding reliability can only be achieved when the equipment is
plugged into a receptacle marked “Hospital Grade”. Any
interruption of the Protective Earth conductor will result in a
potential shock hazard which cause injury to patient or operator.
1.1 Device Classification
Classifications as per EN 60601-1, the manufacturer describes the G4 as:
Type of protection against Electric Shock Class I
Degree of protection against Electric Shock Type BF Defibrillator Protected
Degree of harmful ingress of water IPX0 Ordinary
Mode of Operation Continuous use
Degree of Safety in the Presence of Flammable
Anesthetic Mixture with Air, Oxygen, or Nitrous
Oxide
Not suitable for use
1.2 Electrical Safety and EMC

Cosman G4 Radiofrequency Generator Service Manual (SPI 11291 Rev A)
Section 1
The G4 has been tested to and meets the requirements of the following Electrical Safety Standards:
EN 60601-1 Medical Electrical Equipment (1990, A1: 1993, A2: 1995, A13: 1996)
EN 60601-2-2 Particular Requirements for the Safety of High Frequency
Surgical Equipment (2006)
The G4 has been tested to and meets the requirements of the following EMC Standards:
EN 60601-1-2 Collateral Standards: Electromagnetic Compatibility (2001, A1: 2004)
The following standards apply:
CISPR 11/FCC Part 15 Group 1, Class A, ISM
IEC 61000-4-2 (2001), 61000-4-3 (2006), 610004-4 (2004), 61000-4-5 (2005)
1.3 Electrical Safety Information
The G4 is a radiofrequency generator designed to produce local tissue heating at the tip of an electrode
by the presence of radio frequency current. Special isolation transformers are imposed between power
lines and internal G4 circuitry, resulting in very low leakage current.
WARNING:
A
needle electrode should not be used as the dispersive electrode, as it
is possible to burn the patient at this site due to high current densities. In all
applications, care should be taken to maximize the surface area of the dispersive
electrode. The dispersive electrode should be reliably attached with its entire area
against the patient’s body and as close to the operating field as possible.
The risk of igniting flammable gases or other materials is inherent in lesioning and cannot be eliminated
by device design. Precautions must be taken to restrict flammable materials and substances from the
electrosurgical site. The use of flammable anesthetics and nitrous oxide and oxygen should be avoided,
unless these agents are suctioned away. Flammable agents used for cleaning or disinfecting should be
allowed to evaporate before the application of RF surgery. There is a risk of flammable solutions
pooling under the patient and in body cavities. Any fluid pooled in these areas should be removed
before the equipment is used. Avoid use of flammable materials, such as gauze or cotton wool when
saturated with oxygen. These materials may be ignited by sparks produced in the normal operation of
the G4.

Cosman G4 Radiofrequency Generator Service Manual (SPI 11291 Rev A)
Section 1
WARNING: Apparent low power output or failure of the equipment to function
correctly at normal settings may indicate faulty application of the dispersive
electrode or failure of an electrical lead. Do not increase power before checking for
obvious defects or misapplication. Effective contact between the patient and the
dispersive electrode must be verified whenever the patient is repositioned after the
initial application of the dispersive electrode.
WARNING: Electromagnetic interference (EMI) produced by the unit during normal
operation may adversely affect the performance of other equipment. The
performance of this device may be adversely affected by other high frequency
surgical devices in close proximity. If a problem occurs, separate the devices.
WARNING: The use and proper placement of dispersive electrodes is a key
element in the safe and effective use of this lesion generator, particularly in the
prevention of burns. Read and follow Cosman’s dispersive electrode instructions for
preparation, placement, surveillance, removal and use of any dispersive electrode.
The use of dispersive electrodes that meet or exceed ANSI/AAMI requirements
(HF18) is recommended.
WARNING: Use the Cosman’s DGP-PM large area dispersive electrode, a large
area gel-pad (with a 110 cm² conductive plate area) or an equivalent gel-pad
dispersive electrode (with at least 110 cm² conductive plate area) to disperse and
return RF current over as large an area as possible, and thus minimize heating
effects at that electrode, and to avoid high current densities and resultant burns in
adjacent tissue.
NOTICE: The ground pad should be placed in close proximity to the lesion site.
WARNING: Observe the dispersive electrode during lesioning for signs of excessive
heating.
WARNING: The long-term risks of creation of RF lesions have not been
established.
WARNING: The generator is capable of delivering a significant amount of output.
Patient or operator injury can result from improper handling of the active electrode
and dispersive electrode, particularly when operating the generator. During energy
delivery, the patient should not be allowed to come in contact with metal parts which
are earthed or which have an appreciable capacitance to earth. The use of
antistatic sheeting is recommended for this purpose. Unshielded leads (active or
return) should be positioned so that they cannot come into contact with the patient
or other leads connected to the patient and so that they do not run parallel to nearby
leads.
WARNING: Electrodes and probes of monitoring, stimulating, and imaging devices
can provide paths for high frequency currents even if they are battery powered,
insulated, or isolated at 60 Hz. The risk of burns can be reduced. But not
eliminated, by placing the electrodes or probes as far away as possible from the
lesion site and from the dispersive electrode. Protective impedances incorporated
into the monitoring leads may further reduce the risk of these burns and permit
continuous monitoring during energy delivery. Needles should not be used as
monitoring electrodes during such procedures.

Cosman G4 Radiofrequency Generator Service Manual (SPI 11291 Rev A)
Section 1
WARNING: Potentially hazardous conditions may exist when accessories of similar
connector types are combined. Use only appropriate accessories certified by an
accredited test body.
WARNING: Never proceed in a temperature monitored procedure if the generator
does not read body temperature before you begin delivering RF energy.
WARNING: Raise the temperature slowly, particularly with large electrodes.
Displayed temperature lags behind the actual temperature due to the thermal mass
of the electrode.
WARNING: Verify functional safety of the device before each use, using the
guidelines detailed in this manual.
WARNING: The output of any electrode may change when patient output is being
delivered. Do not move electrode(s) or change electrode connections to the
generator when patient output is being delivered to any electrode.
WARNING: To avoid unanticipated stimulation to the patient, do not cycle the
generator power or turn the generator power on while the patient is connected to the
generator.
NOTICE: Always have spare electrodes and cables on hand in case a problem
arises with the first one during a procedure. Reuseable cables and accessories
should be periodically tested.
NOTICE: Use of DGP-PM ground pad with a stainless steel RF Cannula may
provide a galvanic potential (the “battery effect”) resulting in a single stimulation
pulse at the time the TC Electrode is placed into an RF Cannula. This should be
anticipated, and does not present any risk or danger to the patient.
NOTICE: Always record the wattage readings that correspond to a given
temperature for a given technique. This gives extra guidance and helps Cosman
Medical diagnose problems.
WARNING: Proper electrode placement should be verified using anatomical
landmarks, sensory and motor stimulation techniques, fluoroscopic guidance,
Impedance reading, and good clinical judgment before RF lesion making procedures
are initiated.

Cosman G4 Radiofrequency Generator Service Manual (SPI 11291 Rev A)
1.4 Key to Device Markings
Mains Power
Mains Power On Switch
Main Power Off Switch
Output Control
Front-panel Start Button (Turn on electrode output)
Front-panel Stop Button (Turn off electrode output)
Output Control Knob
Output Connections
Reference Ground Pad Connection and all RF Electrode
Output Connections isolated at low and high leakage
currents
G Reference Ground Pad Connection (on front panel)
1RF Electrode Output Connection 1 (on front panel)
Section 1

Cosman G4 Radiofrequency Generator Service Manual (SPI 11291 Rev A)
2RF Electrode Output Connection 2 (on front panel)
3RF Electrode Output Connection 3 (on front panel)
4RF Electrode Output Connection 4 (on front panel)
Other Connections
Footswitch Remote Control Connection
Equipotential Jack Terminal
USB Connection (Printer or Memory Stick)
Readings and Indicators
Output On Indicator Light
°C Temperature (Degrees Celsius)
ΩImpedance (Ohms)
VVoltage (Volts)
mA Current (Milliamps)
WPower (Watts)
ms Pulse Duration/Width (millisecons)
Hz Pulse Rate/Frequency (Hertz = 1/Seconds)
min Time (Minutes:Seconds)
Section 1

Cosman G4 Radiofrequency Generator Service Manual (SPI 11291 Rev A)
DANGER
REF
LOT
SN
Certifications
Unit is compliant with the European Council Directive
93/42/EEC , Medical Device Directive
Unit is approved by CSA to the US standard
Warnings
Warning: Consult Operator’s Manual.
Warning: Dangerous Voltage. No user-serviceable parts
inside.
Fuse Warning: Replace as marked. Fire Hazard.
Explosion risk if used with flammable anesthetics.
Unit Identification
Reorder Number / Catalog Number
Lot number
Serial Number
Date of Manufacture
Section 1

Cosman G4 Radiofrequency Generator Service Manual (SPI 11291 Rev A)
Other
Type BF protection against electric shock. Floating or
isolated applied part/defibrillator protected.
~Alternating current (AC)
Screen Shot: Save image of screen to Procedure Record
IPX0 Protection against ingression of water: Ordinary
Section 1

Cosman G4 Radiofrequency Generator Service Manual (SPI 11291 Rev A)
2. Chassis Layout
2.1 Front Panel Layout
Front-panel Start Button:
Turn on electrode output
when the Stimulation (Sec.
8.1 & 9.1), Thermal RF
(Sec. 8.2 & 9.2), or Pulsed
RF (Sec. 8.3 & 0) screens
are displayed.
Touch Screen Output On Indicato
r
:
Illuminated when any
electrode out
p
ut is on
Output Control Knob:
Manual output ramping.
Disabled in some modes.
Front-panel Stop Button:
Turn off electrode output
Reference Ground
Pad Connection (G)
Adjustable
Feet
Electrode Output
Connection 1
Electrode Output
Connection 2
Electrode Output
Connection 3
Electrode Output
Connection 4
Notes:
• Electrode connections are made by attaching a CB112-TC cable to an “Electrode Output
Connection” jack (gray) shown above.
• Patient “Reference” connection is made by attaching a CB103-B black cable or the DGP-PM Ground
Pad to the “Reference Ground Pad Connection” jack (black) shown above.
Section 2

Cosman G4 Radiofrequency Generator Service Manual (SPI 11291 Rev A)
2.2 Back Panel Layout
USB Connection: A
printer or external USB
disk.
ttach
Electric Shock Hazard
DO NOT REMOVE COVERS
No User Serviceable Parts
RISK OF FIRE.
REPLACE FUSE AS MARKED.
T2AL250V
100/120/220/ 240VAC ~50/60 Hz
DANGER
Explosion risk if used with
flammableanesthetics.
Risque D’Explosion. Ne Pas
employer en presence
d’anesthesiques inflammables.
COSMAN MEDICAL , INC. Burlington, MA 01803 USA
RFG-4
Fuse box and Mains AC
Voltage Selection:
• 100 Vac
• 120 Vac
• 220 Vac
• 240 Vac
Mains Power Switch
Footswitch
Connection
Equipotential
Connection
Mains AC Power
Cord Connection
Notes:
• Footswitch Connection: If the optional Footswitch is connected it will function as the Start button
when pressed and the Stop button when released in Stimulation, Thermal RF, and Pulsed RF
modes. All other functions of the unit remain the same.
• Equipotential Connection: This connection may be used to tie the chassis ground of different pieces
of equipment together.
WARNING: When connecting any non-medical peripheral equipment to this device,
it must be ensured that the equipment combination meets the requirements of
IEC 60601-1-1.
Section 2

Cosman G4 Radiofrequency Generator Service Manual (SPI 11291 Rev A)
3. Getting Started
3.1 Description
The G4 is a lesion generator capable of supplying up to 50 watts of radiofrequency power while
continuously monitoring both the tissue impedance and the temperature at the tip of the one, two, three, or
four electrodes. All of these functions are described in more detail in subsequent chapters.
3.2 Indications for Use
The Cosman G4 Radiofrequency Generator is indicated for use in procedures to create radiofrequency
lesions for the treatment of pain, or for lesioning nerve tissue for functional neurosurgical procedures. The
Cosman G4 Radiofrequency Generator is used with separately approved Cosman Radiofrequency Probes.
3.3 Unpacking the G4 System
G4 Box Contains:
G4 RF Lesion Generator
C119 Power Cord, Domestic (120 V) or
C118 Power Cord, International (220 V)
CB112-TC Connecting Cable for Electrodes
RFG-TP Test Plug
Operator’s Manual
NOTICE: Place the Operator’s Manual in a safe place for later reference.
NOTICE: Save packaging materials for use in the event that the Generator is
shipped back to Cosman Medical, Inc.
4. Turning on the G4 & Main Menu
1. After unpacking the G4 from the shipping box, plug the power cord into the rear of the unit.
CAUTION: Make sure that the wall outlet voltage matches the voltage displayed on
the Voltage Selector located on the rear of unit (100, 120, 220, or 240). If not, open
the Fuse drawer, remove the Voltage Selector and rotate it to the proper voltage
setting.
2. Plug the power cord into the proper AC receptacle. Rotate the G4’s adjustable feet (Section 2.1)
downward change the viewing angle of the front panel.
CAUTION: Disconnect all electrodes, ground pad, and associated cables from the
G4 before turnin
g
the mains
p
ower on or off.
3. Press the Main Power On Switch on the back panel of the generator (Section 2.2). The startup
screen appears in approximately 2 seconds, and it is displayed for approximately 15 seconds.
Section 3

Cosman G4 Radiofrequency Generator Service Manual (SPI 11291 Rev A)
4. If the Time and Date is set, the Main Menu screen is displayed. If the Time and Date is not set, the
System Setup screen is displayed and the Time and Date must be set (Section 5.1).
Section 4
Generator Mains Power is Off
Press Mains Power On Switch on
back panel of generator (Section
2.2). Wait for 2 sec delay.
Startup
Screen If Time & Date not set
(15 sec delay)
Set Time and Date
If Time
D t
(15 sec delay)
ate previously se System
Setup
Section 5
Main
Menu
System Setup
Section 5
• Set Time and Date
• Adjust Audio Volume
• Change Language
• Calibrate Touch Screen
Records
• Review, Edit, Print,
Export, or Delete
Procedure Records
saved on the generator
Start Procedure
Section 6
• Load or Modify Personal
Settings Presets
• Produce Stimulation,
Thermal RF, or Pulsed
RF output.
System
Setup
Records
Start
Procedure

Cosman G4 Radiofrequency Generator Service Manual (SPI 11291 Rev A)
5. System Setup
Section 5
5.1 Date, Time, Language, and Audio Volume
Press
"Calibrate"
Main Menu
Section 4
Set Time
(Hour, Minute, AM/PM)
Set Date
(Month, Day, Year)
Change Audio
Volume
Press
“Main Menu”
Main Menu
Section 4
• Start Procedure
• Records
•
S
y
stem Setu
p
Touch Screen
Calibration
Section 5.2
Press
“Calibrate”
Change
Language

Cosman G4 Radiofrequency Generator Service Manual (SPI 11291 Rev A)
5.2 Touch Screen Calibration
1. Carefully press and briefly hold the center of each cross-shaped target. Lift your finger or stylus
from the screen and repeat when the target moves. Lift your finger from the screen when the target
disappears.
2. When the cross symbol disappears, press anywhere on the screen to return to the System Setup
screen (Section 5.1).
3. Before enabling any generator output, verify the calibration by pressing on-screen buttons that
appear in a variety of locations across the screen. For instance, press each button or drop-down
menu, except the “Calibrate” button, on the System Setup and Main Menu screens. For each tested
button, confirm that a button press is recognized if and only if the screen is pressed within the visible
border of that button. If this test fails for any tested button, repeat the touch screen calibration.
WARNING: Poor calibration of the touch screen may cause user input to be
recognized incorrectly.
NOTICE: Light use of a blunt, plastic stylus (such as that from a touch-screen PDA)
to precisely target the cross symbols may improve touch screen calibration. Damage
to the touch screen could occur if too much pressure is applied or if a sharp object is
used to touch the screen.
NOTICE: Ignore the text “Press the Esc key to cancel”. Touch screen calibration
cannot be canceled.
Calibration
Complete
Press
"Calibrate"
System Setup
Section 5.1
Target
Center
Calibration
Screen
Section 5

Cosman G4 Radiofrequency Generator Service Manual (SPI 11291 Rev A)
Section 5
5.3 Testing the G4 Unit
The ability of the generator to produce RF output and to measure Temperature and Impedance can be
tested by attaching one or more Test Plugs (RFG-TP) to active electrode jacks and performing a procedure.
When a Test Plug is attached to an active electrode jack and the output is off, check that the displayed
Impedance is approximately 100 and the displayed Temperature is approximately room Temperature.