Comen CM300 User manual

Three-Channel Electrocardiograph
CM300
Service Manual
Shenzhen Comen Medical Instrument Co., Ltd.

Shenzhen Comen Medical Instruments co., ltd.
Content
Chapter 1 Safety Guidance........................................................................................................1
1.1 Safety Information ....................................................................................................1
1.1.1 Danger...............................................................................................................1
1.1.2 Warnings ...........................................................................................................2
1.1.3 Cautions ............................................................................................................4
1.1.4 Notes .................................................................................................................6
1.2 Equipment Symbols ..................................................................................................6
Chapter 2 Warranty and Service........................................................................................................7
2.1 Warranty Terms.........................................................................................................7
2.2 What is excluded?.....................................................................................................7
2.3 Service Procedure......................................................................................................8
2.4 Fill in the Service Claim Form (SCF).......................................................................8
2.5 Send COMEN the SCF and Select a Solution...........................................................8
2.6 Obtain the RMA Form ..............................................................................................9
2.7 Send the Parts to COMEN ........................................................................................9
2.7.1 Contact Information ........................................................................................10
Chapter 3 Principle introduction.....................................................................................................11
3.1 CM300 system principle block diagram .................................................................11
3.2 CM300 Module Introduction ..................................................................................11
3.2.1 Main board (2410 core board + CM300 bottom board)..................................11
3.2.2 3.2.2CM100_300 ECG Board.........................................................................12
3.2.3 R-type transformer:.........................................................................................13
3.2.4 LCD Adapter Board ........................................................................................13
Chapter 4 Trouble Shooting............................................................................................................14
4.1 Introduction.............................................................................................................14
4.2 Part Replacement ....................................................................................................14
4.3 Checking Software Version.....................................................................................14
4.4 Checking Technical Alarms.....................................................................................14
4.5 Troubleshooting Guide............................................................................................15
4.5.1 4.5.1 Failure to power on with AC supply ......................................................15
4.5.2 Failure to power on with battery .....................................................................15
4.5.3 4.5.3 White or Black Screen............................................................................15
4.5.4 Abnormal screen display.................................................................................16
4.5.5 No ECG output from certain lead. ..................................................................16
4.5.6 ECG disturbance. ............................................................................................16
4.5.7 Electromyograhic disturbance.........................................................................17
4.5.8 Unstable baseline ............................................................................................17
4.5.9 Partial buttons or all buttons failure................................................................18
4.5.10 Print problem...................................................................................................18
Chapter 5 Performance Verification................................................................................................20
5.1 Safety Test...............................................................................................................20
5.2 Performance Tests....................................................................................................20

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5.2.1 ECG Performance test.....................................................................................20
5.2.2 Print speed test ................................................................................................20
Chapter 6 Disassembling Procedure ...............................................................................................22
6.1 Disassemble the rear panel......................................................................................22
6.2 Separate the function board in the front panel. .......................................................23
6.3 Disassemble the ECG board....................................................................................25
6.4 Disassemble the main board....................................................................................26
6.5 Disassemble the power unit ....................................................................................26
6.6 Printer disassembling..............................................................................................27
Chapter 7 Software Upgrade...........................................................................................................28
7.1 Tools........................................................................................................................28
7.2 Preparation before Upgrade System Software ........................................................28
7.3 System Software Upgrade.......................................................................................28

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Chapter 1 Safety Guidance
1.1 Safety Information
The design of the 3-channel electrocardiograph complies with international standard IEC 60601-1
Medical Electrical Equipment: General Requirements for Safety and IEC 60601-2-25 Particular
Requirements for the Safety of Electrocardiographs etc. The classification of this equipment is
Class І, type CF, which means a higher degree of protection against electric shock and the patient
connection is fully isolated and defibrillation protected.
This equipment is not explosion-proof. Do not use it in the presence of flammable
anesthetics.
This equipment is designed for continuous operation and is ‘ordinary’ (i.e. not drip or
splash-proof).
Classification:
Anti-electric-shock type:
Class І with internal power supply
Anti-electric-shock degree:
CF
Degree of protection against harmful
ingress of water:
Ordinary equipment (Sealed equipment without
liquid proof)
Disinfection/sterilization method:
Refer to the user manual for details
Degree of safety of application in the
presence of flammable gas:
Equipment not suitable for use in the presence
of flammable gas
Working Mode:
Continuous operation
EMC:
Group І, Class A
1.1.1 Danger
There are no dangers that refer to the product in general. Specific “Danger” statements may be
given in the respective sections of this manual.

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1.1.2 Warnings
In order to use the electrocardiograph safely and effectively, avoiding possible dangers caused by
improper operations, please read through the user manual and be sure to be familiar with all
functions of the equipment and proper operation procedures before use.
Please pay more attention to the following warning and caution information.
1.1.2.1 Safety Warnings
WARNING :
♦The electrocardiograph is provided forthe use of qualified physicians or
personnel professionally trained. And they should be familiar with the
contents of this user manual before operation.
♦Only qualified service engineers can install this equipment. And only
service engineers authorized by our company can open the shell.
♦Only qualified installation or service engineers can shift the mains shift
switch (100V~115V/220V~240V) according to local mains supply.
♦The results given by the equipment should be examined with respect to
the overall clinical condition of the patient.And it can not substitute for
regular checking.
WARNING :
♦EXPLOSION HAZARD-Do not use the electrocardiograph in the
presence of flammable anesthetic mixture with oxygen or other
flammable agents.
♦SHOCK HAZARD-The power receptacle must be a hospital grade
grounded outlet. Never try to adapt the three-prong plug to fit a
two-slot outlet.
♦If the integrity of external protective conductor in installation or
arrangement is in doubt, the equipment should be operated from the
built-in rechargeable battery.
♦Do not use this equipment in the presence of high static electricity or
high voltage equipment which may generate sparks.
♦This equipment is not designed for internal use and direct cardiac

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application.
WARNING :
♦Only patient cable and other accessories supplied by our company can
be used. Or else, the performance and electric shock protection can not
be guaranteed.
♦Be sure that all electrodes have been connected to the patient correctly
before operation.
♦Be sure that the conductive parts of electrodes and associated
connectors, including neutral electrode, should not contact with earth
or any other conducting objects.
♦Electrodes with defibrillator protection should be used while
defibrillating.
♦There is no danger for patients with pacemaker.
♦Do not touch the patient, bed, table and the equipment while using
defibrillator or pacemaker simultaneously.
♦In order to avoid burning, please keep the electrode far away from the
radio knife while using electrosurgical equipment simultaneously.
WARNING :
♦Accessory equipment connected to the analog and digital interfaces
must be certified according to the respective IEC standards (e.g. IEC
60950 for data processing equipment and IEC 60601-1 for medical
equipment). Furthermore all configurations shall comply with the valid
version of the standard IEC 60601-1-1. Therefore anybody, who
connects additional equipment to the signal input connector or output
connector to configure a medical system, must make sure that it
complies with the requirements of the valid version of the system
standard IEC 60601-1-1. If in doubt, consult our technical service
department or your local distributor.
♦The summation of leakage current should never exceed leakage current
limits while several other units are used at the same time.
♦The potential equalization conductor can be connected to that of other
equipment when necessary, to make sure that all these equipment are

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connected with the potential equalization bus bar of the electrical
installation.
1.1.2.2 Battery Care Warnings
WARNING :
♦Improper operation may cause the battery to be hot, ignited orexploded,
and it may lead to the declination of battery’s capacity. It is necessary to
read the user manual carefully and pay more attention to warning
messages.
♦Only qualified service engineer authorized by our company can open
the battery compartment and replace the battery. And the battery of
same model and specification provided by manufacturer should be
used.
♦Danger of explosion -- Do not reverse the anode and cathode when
connecting the battery.
♦Do not heat or splash the battery or throw it into fire or water.
♦When leakage or foul smell found, stop using the battery immediately. If
your skin or cloth comes into contact with the leakage liquid, cleanse it
with clean water at once. If the leakage liquid splashes into your eyes, do
not wipe them. Irrigate them with clean water first and go to see a
doctor immediately.
♦When the battery’s useful life is over, contact with the manufacturer or
local distributor for disposal or dispose the battery according to local
regulations.
1.1.3 Cautions
CAUTION :
♦Avoid liquid splash and excessive temperature. The temperature must
be kept between 5℃and 40℃while working. And it should be kept
between -20℃and 55℃during transportation and storage.
♦Do not use the equipment in dusty environment with bad ventilation or
in the presence of corrosive.

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♦Be sure that there is no intense electromagnetic interference source
around the equipment, such as radio transmitter or mobile phone etc.
Attention: large medical electrical equipment such as electrosurgical
equipment, radiological equipment and magnetic resonance imaging
equipment etc. are likely to bring electromagnetic interference.
CAUTION :
♦Before use, the equipment, patient cable and electrodes etc. should be
checked. Replacement should be taken if there is any evident
defectiveness or aging symptom which may impair the safety or
performance.
♦The following safety checks should be performed at least every 24
months by a qualified person who has adequate training, knowledge,
and practical experience to perform these tests.
a)Inspect the equipment and accessories for mechanical and
functional damage.
b) Inspect the safety relevant labels for legibility.
c)Inspect the fuse to verify compliance with rated current and
breaking characteristics.
d) Verify the device functions properly as described in the
instructions for use.
e)Test the protection earth resistance according IEC 601-1/1988:
Limit 0.2 ohm.
f) Test the earth leakage current according IEC 601-1/1988: Limit:
NC 500 uA, SFC 1000uA.
g)Test the patient leakage current according IEC 601-1/1988: Limit:
10 uA(CF).
h) Test the patient leakage current under single fault condition with
mains voltage on the applied part according IEC 601-1/1988:
Limit: 50uA (CF).
The data should be recorded in an equipment log. If the device is not
functioning properly or fails any of the above tests, the device has to be
repaired.
♦Ruptured fused must only be replaced with the same type and rating as
the original.
♦The equipment and reusable accessories can be sent back to the
manufacturer for recycling or proper disposal after their useful lives.

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1.1.3.1 Cleaning & Disinfection Cautions
CAUTION :
♦Turn off the power before cleaning and disinfection. If mains supply
used, the power cord should be drugged out of the outlet also. And
prevent the detergent from seeping into the equipment.
♦Do not immerse the unit or patient cable into liquid under any
circumstances.
♦Do not clean the unit and accessories with abrasive fabric and avoid
scratching the electrodes.
♦Any remainder of detergent should be removed from the unit and
patient cable after cleaning.
♦Do not use chloric disinfectant such as chloride and sodium
hypochlorite etc.
♦Do not use high temperature, autoclaving or radiation sterilization
processes.
1.1.4 Notes
Refer to Operation Manual for detailed operation and other information.
1.2 Equipment Symbols
External output
Potential equalization
External input
Mains supply
Equipment or part of CF type
with defibrillator proof
Battery indicator
Attention –general warning (see
accompanying document)
Battery recharging indicator

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Chapter 2 Warranty and Service
2.1 Warranty Terms
COMEN provides an 18 months warranty for the warranted products (main unit) and 3 months
for the accessories. The warranty period begins on the date products are shipped to customer. If
a customer promptly notifies COMEN of customer’s warranty claim hereunder, COMEN will either
repair, adjust or replace (with new or exchange replacement parts) COMEN’s products. COMEN
warrants that any service it provides to customers will be performed by trained individuals in a
workmanlike manner.
2.2 What is excluded?
The warranty does not cover for the situations caused by the following condition:
Malfunction or damage caused by improper use or man-made failure.
Malfunction or damage caused by unstable or out-of-range power input.
Malfunction or damage caused by force majeure such as fire and earthquake.
Malfunction or damage caused by improper operation or repair by unqualified or unauthorized
service people.
Malfunction or damage caused by use of parts or accessories not approved by COMEN.
Malfunction of the instrument or part whose serial number is not legible enough.
Others not caused by instrument or part itself.

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2.3 Service Procedure
2.4 Fill in the Service Claim Form (SCF)
Fill in the SCF with detailed information including: Model Name, Serial Number (SN) and Problem
Phenomena. COMEN should not have any obligation to take over the case without this
information. The form can be gotten from COMEN’s Service Department.
2.5 Send COMEN the SCF and Select a Solution
Once the service department receives the fully filled SCF, COMEN’s engineer will offer a solution
in three working days. COMEN will follow out the case based on the two conditions below:
Within Warranty:
There are two options:
1) After receiving the Return Material Authorization (RMA) form from COMEN service
department, customer sends COMEN the defective parts and informs about the shipment
tracking number. Then we will dispatch new part(s) to your confirmed address with confirmed
shipping invoice.
2) The customer signs the Declaration Form and sends it back by email or fax. This form is legally
certificated to make sure the customer or end-user will return the defective parts to COMEN on
time. We will, at this option, dispatch the replacement one(s) with confirmed shipping invoice.

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NOTE:
Both Return Material Authorization Form and Declaration Form are offered by
COMEN service department once the SCF is confirmed by service engineer.
The customer is responsible for freight& insurance charges when the equipment is
shipped to COMEN for service, including custom charges. COMEN is responsible for the
freight, insurance & custom charges from COMEN to the customer.
Out of Warranty:
After receiving the RMA form from the service department, the customer sends defective parts
to COMEN in advance. We will analyze the problems and discuss with the customer about either
repairing or replacing the part(s). Once the maintenance fee is invoiced and paid, we will make
sure to dispatch good part(s) to the confirmed address.
NOTE:
The customer is responsible for any freight & insurance charge for the returned product.
2.6 Obtain the RMA Form
Before the shipment of the materials, the customer must obtain an RMA form from our service
department, in which the RMA number, description of returning parts and shipping instructions
are included. The RMA number should be indicated on the outside of the shipping container.
NOTE:
COMEN should not have any obligation to the end-user or customer who returns the
goods without the notification by COMEN’s service department. The sender takes full
responsibility for the accounted fee.
2.7 Send the Parts to COMEN
Follow these recommended instructions:
Please disassemble the parts with anti-static facility, do not touch the parts with naked hand.
Please pack the parts safely before return.
Please put the RMA number on the parcel.
Please describe the returned parts as ‘sample of *****’ and put the total value on the invoice,
and note on the invoice as ‘sample, no commercial value’.
Please confirm the information (such as price in invoice, address and other necessary issues)
with COMEN before shipment.
Please send back the parts after COMEN’s confirmation.

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2.7.1 Contact Information
If you have any question about maintenance, technical specifications or malfunctions of devices,
do not hesitate to contact us.
•COMEN International After-Sale Dept.
•Monday to Friday 09:00-18:00 (UTC +08:00)
•E-mail: [e-mail]
•Tel: + 86 -755- 26431236-333
•Fax: + 86 -755-26431232
Add: Floor8, Block3, 4th Nanyou Industrial,
Nanshan District, 518052 Shenzhen, China

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Chapter 3 Principle introduction
3.1 CM300 system principle block diagram
3.2 CM300 Module Introduction
3.2.1 Main board (2410 core board + CM300 bottom board)
The main board is the heart of the instrument. It consists of bottom board and core board (CPU
board), it implements a series of tasks including CPU system, display processing, printing control,
keyboard signal processing. CPU system receives electrocardiogram signal that collects by ECG
board, and send to recorder after printing control system. CPU system receives also signals from
button board to finish the button board signal process, moreover, signals of lead-fall, paper
detecting, battery management are all processed by main board CPU. The main board also
process print task, CPU system receives order and data from print control system, generate
control signals for stepping motor and printer head to implements waveforms and other
information’s print. CPU system also sends order and data to display waveforms and other
R-Type
transformer
LCD Panel
Inverter
USB interface
Recorder
Battery
COM interface
Main board
Button
board
To
Patient
USB device
User
AC Input
CM100_300
ECG board

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information.
PIN ID
CON7
CON10
CON11
CON12
Description
To LCD adapter
board
To ECG board
Main board
Power socket
To recorder
Working voltage
5V
20V（AC）
Module Function
Data storage, the CPU of the main unit, display circuit, network circuit,
recorder circuit and I/O interface.
3.2.2 3.2.2CM100_300 ECG Board
ECG board process the ECG signal gets from ECG cable. It implements signal amplification
including analog circuit, A/D converter and control circuit.
Analog circuit consists of lead signal amplification, channel switch, anti-alias filter, gain control,
lead-off detection. Control circuit is Responsible for coordinating with A/D convertor, channel
switch, gain control circuit and lead-off detection circuit to implement signal acquisition and
lead-off detection, the digital lead signal will then be sent to CPU by high speed photo-coupler.
PIN ID
P1
Description
ECG board socket, to main board
Working voltage
5V
Module Function
Measure ECG data

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3.2.3 R-type transformer:
PIN ID
Description
Working voltage
Module Function
Voltage transformation to feed main board
3.2.4 LCD Adapter Board
PIN ID
P1
P2
P4
Description
To LCD panel
To main board
To Membrane
button
Working voltage
Module Function
LCD and button signal transmit

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Chapter 4 Trouble Shooting
4.1 Introduction
In this chapter, electrocardiograph problems are listed along with possible causes and
recommended corrective actions. Refer to the tables to check the electrocardiograph, identify
and eliminate the troubles.
The troubles we list here are frequently arisen difficulties and the actions we recommend can
correct most problems, but not all of them. For more information on troubleshooting, contact
our Customer Service Department.
4.2 Part Replacement
Printed circuit boards (PCBs), major parts and components in the electrocardiograph are
replaceable. Once you isolate a PCB you suspect defective, follow the instructions in 7
Disassembly and repair to replace the PCB with a known good one and check that the trouble
disappears or the patient monitor passes all performance tests. Defective PCB can be sent to us
for repair. If the trouble remains, exchange the replacement PCB with the original suspicious PCB
and continue troubleshooting as directed in this chapter.
To obtain information on replacement parts or order them, refer to 3Principle introduction.
4.3 Checking Software Version
Some troubleshooting may involve software compatibility. Thus it requires you to your
electrocardiograph configuration and software version. For detailed information on version
compatibility, please contact our Customer Service Department.
To view information on the electrocardiograph system software version, select
[Menu]→[Net]→[Software Version ].
4.4 Checking Technical Alarms
Before troubleshooting the electrocardiograph, check for technical alarm messages. If an alarm

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message is presented, eliminate the technical alarm first.
For detailed information on technical alarm message, possible cause and corrective action refer
to the electrocardiograph’s Operation Manual.
4.5 Troubleshooting Guide
4.5.1 4.5.1 Failure to power on with AC supply
Symptoms
Possible Cause
Correction Action
The electrocardiograph
fails to start with AC
power.
AC power supply cable is not
connected well.
Check whether the power supply cable is
reliably connected
The two fuses defective
Remove power supply cable and open the
fuse-boxes then ensure each of them is
good by multi-meter. If not, change new
fuses.
AC power supply unit defective
Switch the multi-meter to AC voltage gear
and test the transformer output. The
reasonable output should be 18V-20V
Main board defective
replace a new main board
Keypad defective
replace a new keypad
4.5.2 Failure to power on with battery
Symptoms
Possible Cause
Correction Action
The electrocardiograph
fails to start with
battery.
Battery defective.
Check the battery voltage is around 14.8V
Main board defective
replace a new main board
4.5.3 4.5.3 White or Black Screen
Symptoms
Possible Cause
Correction Action
White or Black screen
Keypad cable or connect cable is
Check the keypad cable or connector cable

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not connect well.
is reliably connected
System failure
replace a main board
LCD screen defective
replace a LCD screen
4.5.4 Abnormal screen display
Symptoms
Possible Cause
Correction Action
Abnormal screen
display
LCD adapter board or LCD cable not
connect well
Check LCD adapter board or LCD cable
connect well
LCD adapter board or LCD cable
defective
replace a LCD adapter board or LCD cable
LCD screen defective
replace a new LCD screen
4.5.5 No ECG output from certain lead.
Symptoms
Possible Cause
Correction Action
No ECG output from
certain lead.
Identical electrode falls off or has
no reliable linked with patient body
re-install the electrode or paste some
water or conductive ointment at the
contact position
Cable has been broken due to long
time use or unit aging/clamp
electrodes or chest bulbs lose
flexibility or weak connection
The cable and electrode of the same
model shall be used to replace the old one.
ECG board and main board cable
didn’t connect well.
Check the internal wire between ECG
board and main board connect well.
ECG board defective
Change the new ECG board
Main board defective
Change the new main board
4.5.6 ECG disturbance.
Symptoms
Possible Cause
Correction Action

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ECG disturbance
Identical electrode had no reliable
linked with patient body;
re-install the electrode or paste some
water or conductive ointment at the
contact position
ECG machine, electrode, metal bed
or lead cable reliably connected with
grounding
Check ECG machine, electrode, metal bed
or lead cable reliably connected with
grounding
Disturb by electric equipments of
large power wor 的king nearby
Check if there is disturb by electric
equipments of large power working nearby
Electrode and skin pasted with
sufficient conductive ointment.
Switch on the ECG filtering function of the
machine
The patient wearing jewelry such as
glasses or gems, AC disturbance can
not be cleared.
Switch on the ECG filtering function of the
machine
4.5.7 Electromyograhic disturbance
Symptoms
Possible Cause
Correction Action
Electromyograhic
disturbance
Communication disturbance
Switch on the shift filtering function of the
machine to 25Hz or 35Hz, and then the
recorded ECG waveforms will reduce a
little bit.
The doctor talk to the patient
during ECG recording process
The Electrode clippers on the
arms and legs too tightened
4.5.8 Unstable baseline
Symptoms
Possible Cause
Correction Action
Unstable baseline
electrode installation stable, lead
cable and electrode connected
properly
Switch on the shifting filtering function of
the machine to 0.1Hz, 0,2Hz or 0.5Hz, the
recorded ECG waveforms will reduce a
little bit.
electrode and patient skin clean
electrode and skin pasted with
sufficient conductive ointment