Innomed Medical Hear Screen 112C-1 User manual

Innomed Medical Heart Screen 112C-1 Service manual
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Service Manual
for
Heart Screen112C-1
Simultaneous 12-channel ECG devices with 112mm wide
3-channel built-in printer and
LCD display

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1 Contents
1CONTENTS.................................................................................................................................................. 2
2THE HEARTSCREEN112C-1.................................................................................................................... 3
3DEVICES’ TECHNICAL PARAMETERS............................................................................................... 4
3.1 GENERAL FEATURES............................................................................................................................... 4
4DEVICES’ COMPONENTS AND THEIR OPERATION....................................................................... 7
4.1 DEVICE BLOCK DIAGRAM OF COMPLETE CONFIGURATION:.................................................................... 7
4.2 HEARTSCREEN112C-1 MAIN BOARD..................................................................................................... 8
4.3 HEARTSCREEN112C-1 MAIN BOARD ANALOG PART BLOCK DIAGRAM.............................................. 10
4.4 HEARTSCREEN112C-1 INTERFACE BLOCK DIAGRAM........................................................................... 11
4.5 BATTERY PACK..................................................................................................................................... 12
4.6 DEVICE MECHANICAL CONSTRUCTION................................................................................................. 13
4.6.1 Devices’ summarized exploded diagrams ....................................................................................... 13
4.6.2 Devices’ base exploded diagram..................................................................................................... 14
4.6.3 HeartScreen112C-1 top exploded diagram..................................................................................... 15
5BOARD LEVEL MEASUREMENTS...................................................................................................... 16
5.1 MAIN BOARD VOLAGE TEST: ............................................................................................................... 16
5.1.1 Checking voltages –digital circuits ................................................................................................ 16
5.1.2 Checking voltages –Analog part..................................................................................................... 16
5.2 VOLTAGE TESTS ON THE “INTERFACE”BOARD..................................................................................... 16
5.2.1 Checking voltages............................................................................................................................ 16
6DEVICE LEVEL MEASUREMENTS..................................................................................................... 17
6.1 HEARTSCREEN112C-1 BASIC FUNCTIONS ........................................................................................... 17
6.2 CHECKING TECHNICAL REQUIREMENTS ................................................................................................ 18
6.2.1 Leakage current measurement ........................................................................................................ 18
6.2.2 Sensitivity examination and DC tolerance checking ....................................................................... 18
6.2.3 Latch-up watch check...................................................................................................................... 19
6.2.4 Measuring noise on the input and baseline checking...................................................................... 19
6.2.5 Checking frequency response.......................................................................................................... 20
6.2.6 Checking filter................................................................................................................................. 21
6.2.7 Checking CMRR.............................................................................................................................. 21
6.2.8 Printing ECG signal........................................................................................................................ 21
6.2.9 Checking PC connection ................................................................................................................. 22
7MAINTENANCE AND SERVICE PROCEDURES............................................................................... 22
7.1 DEVICE DISASSEMBLY /ASSEMBLY ...................................................................................................... 22
7.1.1 Disassembly of the bottom part:Remove the battery connections. .................................................. 24
7.2 REPROGRAMMING THE DEVICE............................................................................................................. 25
8POSSIBLE ERRORS AND TROUBLESHOOTING ............................................................................. 26
9ASSEMBLY DRAWINGS......................................................................................................................... 30
9.1 HEARTSCREEN112C-1 MAIN BOARD.................................................................................................... 30
9.2 HEARTSCREEN112C-1 INTERFACE BOARD .......................................................................................... 32
10 SCHEMATICS ........................................................................................................................................... 34
10.1 HEARTSCREEN112C-1 MAIN BOARD................................................................................................... 34
10.2 HEARTSCREEN112C-1 INTERFACE BOARD .......................................................................................... 44
10.3 HEARTSCREEN112C-1 BATTERY PACKAGE......................................................................................... 47

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2 The HeartScreen112C-1
The HeartScreen112C-1 is a battery-operated, modern 12-channel electrocardiograph, used to measure and
graphically record the heart’s bioelectric potential during human heart and circulatory system examination. The
device contains a 8-channel amplifier and ECG signal-processing unit. The built-in thermal printer produces
112mm wide printout. (3-6-12lead). The high-speed 12-channel data transfer over the serial line insures 12-
channel on-line display on the PC.
Due to the menu oriented touch screen control the operation of the device is simple, selecting the basic functions
and the pre-edited record modes, and creating and storing the records need but a few button presses.
Even in its basic configuration the device can be connected to a computer. On-line display of the selected 12
channels and record storage is possible on the PC’s large display. The records stored in the HeartScreen112C-1
are identified by the date and exact time, and also by the automatically generated identification code or manually
entered patient code.
The PC-based cardiological database management system (Innobase for Windows) running under Windows
performs archiving. The program may also be used for on-line ECG monitoring, ECG and diagnosis storage,
search and display. The program system is capable of receiving signals from other Innomed manufactured ECG
devices and record storage.
Devices manufactured and distributed by:
Innomed Medical
Medical Developing and Manufacturing Inc.
H-1146 Budapest, Szabó József u. 12.
(36-1)460-9200 Fax [phone]
E-mail: innom[email protected]
www.innomed.hu

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3 Devices’ technical parameters
Classification according to 93/42/EEC directive: II.a
This product has CE mark according to the 93/42/EEC Council
Directive on medical devices, dated on 14. June 1993.
3.1 General features
Reference temperature range
0... +40 C
Operating temperature range
Humidity
0... +45 C
20…95% humidity (without condensation)
Shipping/storage temperature range
-20... +55C
Operating environment
dry, closed space
Operating and storage pressure
550 –1060 hPa
Environment abstinence
IP20, the device protected from middle-sized solid objects
(>12mm) but it is not protected from water intrusion
Mains and power supply
Mains voltage
110-230VAC
Mains frequency
50 - 60 Hz
Mains power consumption
2A@110VAC 1 A@230VAC
Accumulator type
2100 mAh,
only Innomed produced accumulator is useable.
Accumulator nominal voltage
9,6 V
Accumulator charging time (informative)
In case of totally dead accumulator max. 2 hours
Accumulator charger type, protection
Intelligent quick charger, thermal protection at 54 C, thermal fuse at
90 C
Operating time from accumulator
60 minutes of ECG curve printing in intermittent operating mode, or
8 hours of monitoring (only basic functions are operated)
Safety
Safety class
I.
Patient protection (with PC connection as
well)
Defibrillator protected CF
Operating modes
Monitoring, display
3, 6 or 12-channel monitoring + rhythm channel
Manual printing
Manual printing from any lead groups on 3, 6 or 12 channels
Automatic printing:
Adjustable length automatic printing from the 12 standard ECG leads in 2x6
or 4x3 channel groups.
Record storage (STORE)
Automatic recording and storage from 12 leads. Rhythm curve may be stored
in pre-programmed mode.
Analysis and diagnosis creation
(DGN)
Automatic 12-channel recording with analysis and diagnosis. Raw curve,
rhythm curve may be stored in pre-programmed mode. Data, marked average
curved appearance on the display and printer.
Arrhythmia analysis (ARTM)
Arrhythmia event storage, trends, statistics.
Result appearance on the printer and display.

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Lead groups
Standard:
3 channels: I-III; aVR-aVF; V1-V3; V4-V6
6 channels: I –aVF; V1 –V6
12 channels: I…V6
Cabrera:
3 channels: aVL I -aVR; II aVF III; V1- V3; V4-V6
6 channels: aVL I –aVR II aVF III; V1 V2 V3 V4 V5 V6
12 channels: aV…V6
Heart frequency measurement
Measurement range
30 –300 BPM
Accuracy
1 BPM or 2%
ECG amplifier
Input signal range
10 mV
Frequency response
0,05 Hz…150 Hz +0,-3 dB
Voltage measurement relative error
in the 0,5 - 10 mV range
3%
Sensitivity
2.5, 5, 10, 20 mm/mV Auto
Noise referred to the input
max. 20 Vpp
Input impedance (informative)
min. 20 MOhm
CMRR
min. 100 dB
DC tolerance
min. 320 mV DC
Pacemaker tolerance
max. 700mV/2ms
Pacemaker detection
min.2 mV/0,5 ms max. 700mV/2ms
Time constant
min. 3,2 sec
Patient leakage current
max. 10 A
Electrode failure detection
by channels
Calibrating signal (software generated)
1 mV / 300 ms
Muscle filter (digital)
35 Hz +0/-3 dB
Line filter (digital)
50 / 60 Hz
Line filter - 20 dB point:
50 Hz filter: 48,5 … 51,5 Hz
60 Hz filter: 59 … 61 Hz
Baseline filter (digital)
under 0,3 Hz: complete suppression
over 0,9 Hz: complete transfer
Amplifier error messages
Audio and visual signal in case of
input level error and noisy signal
Patient cable type
Innomed approved patient cable
Defibrillator protected 10-lead cable
4-lead cable
Defibrillator tolerance
Only with defibrillator protected cable!
max. 360 J, 5000 V
Digitalizing features
Data acquisition
12-lead, simultaneous (within 100us)
Sampling frequency
8000 Hz / channel
A/D resolution
24 bit, 0.076uV/bit
Nominal processed signal range
700 mV
Stored signal resolution
500 Hz 10 uV/bit
Resolution in case of PC connection during online ECG
transfer
500 Hz 5 V/bit
Printing features
Effective recording width per channel
40 mm, overlap allowed
Printer head resolution
In amplitude direction: 8 points / mm
On the time axis: 8 or 16 points / mm

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Printing speed
5, 25, 50 mm/s
Paper width
112 mm +0 -1 mm
Paper block (folding)
300 pages, 150 mm long pages
Paper replacement
automatic feed
Warnings
Sound signal when out of paper
Printed data
Date, time, patient identifier code, age, speed,
sensitivity, lead marks, filter status
Printed analysis data
Amplitude and time parameters measured on averaged
QRS cycle, heart frequency, axis positions and Q-T,
P-Q, QRS width and diagnostic categories
The calculated time parameters are signed by markers
on the average curves
Display
Display type
TFT colour, touch screen, size: 7”
Viewing resolution
640 x 480 points
Number of displayed curves
3 channels + with rhythm lead group change
6 channels + with rhythm lead group change
12 (2 x 6) channels
Communication parameters
Communication
USB
Wifi (optional)
Communication services (optional!)
- online monitoring of 12 leads
-ECG device control from PC
-record creation and storage directly on the PC
Mechanical (informative) data
Size
295 x 225 x 80 mm
Weight (informative)
1,9 kg
Pacemaker pulse detection
When the device examines a patient with a pacemaker, recognizes the pacemaker signal within certain ranges according to
the technical parameters and graphically displays on the record. In this case diagnosis is not created, because the pacemaker
pulse may interfere the diagnosis program.
Warning!
There is only analysis creation which the pace impulse does not interfere, but due to the morphological differences there
may be inaccuracies in the numerical data.

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4 Devices’ components and their operation
4.1Device block diagram of complete configuration:

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4.2 HeartScreen112C-1 Main board
Master A/D Slave A/D Processor (U6 !)
Patient connector
USB
Charger
Analog
part
Digital
part

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HS112C-1 Main board Digital Part
Pro-
cessor
(U24 !)
RAM
(U201)
D[0..7]
A[00..18]
PL1
J2
PC
Connection
to
INTERFACE
BOARD
USB
Insulation
Interface
Circuits
ECG data
OPTO
isolator
RTC
(U21)
Mains
Charger
Accu
Pack
Charger
Circuit
U54
RTC & RAM
Power
Supply
U42
+5V Power
Supply
U44
On/Off
Circuit
U51
Reset
Circuit
U5
J4
J14
Serial ECG
data
Test
Connector
J3

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4.3HeartScreen112C-1 Main board Analog Part block diagram
Processor
(U6 !)
MASTER
A/D
(U17)
limb leads
ECG data
opto
isolator
Patient
P2
SLAVE
A/D
(U18)
chest leads
Isolated
power
supply
+VCCAN
+3,3V
power
supply
+3,3V

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4.4HeartScreen112C-1 Interface block diagram
Interface connector J1
Power connector J11
Display
J2
J8
J24
Printer
ON/OFF
button
&
LED
Display
controller
PIC24FJ256DA210
U7
Motor driver
Power supply
+3,3V U9
Head Power U10
J4

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4.5Battery pack
(R-4322-1_HS112C-1_Assembled_Accupack)
The battery pack contains 8 pcs of 2100 mAh rechargeable batteries. The pack is drained at the fourth cell. This
output supplies the date / time IC and the record storing RAM with power when the device is turned off.
We have built a thermistor into the battery pack as well, which checks battery pack heating during charging. As a
final check we have built in a thermal protection fuse that breaks at 90°C. Take note of this fuse when servicing
the device, as it may break with too much heat (for example when soldering). Instead of soldering we
recommend cold extrusion or soldering with continuous cooling.
Warning!
The internal battery provide that not loosen to recorded datas in the memory in case of power loss or power failure. If the
battery disassembly is needed during maintenance or repair; for data security in the internal memory, transfer the data to an
external source before remove to the battery.

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4.6Device mechanical construction
4.6.1 Devices’ summarized exploded diagrams

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4.6.2 Devices’ base exploded diagram

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4.6.3 HeartScreen112C-1 top exploded diagram
Display

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5 Board level measurements
5.1 MAIN board volage test:
5.1.1 Checking voltages –digital circuits
Check digital +5V voltage at test point J3/1 5V +/-5%
Check Vref +2.5V voltage at test point J3/7 5V +/-2%
5.1.2 Checking voltages –Analog part
Check VCCAN buffer voltage at capacitor C109 6V +/-5%
Check analogue power supply 3.3V at JP5 3.3V +/-5%
Check Ref_Master voltage 1.8V at C45 1.8V +/-2%
Check Ref_Slave voltage 1.8V at C74 1.8V +/-2%
5.2 Voltage tests on the “interface” board
5.2.1 Checking voltages
Check voltage on J3/6 pontján: +3,3V +/-5%
Check HEAD VOLTAGE during printing on the two
poles of C23 +7,8V +/-5%

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6 Device level measurements
6.1HeartScreen112C-1 Basic functions
Test procedure
Comment
Patient cable surveillance
(detecting break in the cable)
Connect all the ten banana plugs of the patient cable together, connect the
cable to the device and switch it to monitoring mode.
On the display there must not be wrong lead detection, all the leads quality
indicators have to be green. During the test the device has to monitor zero
line on all leads.
Try to turn the cable at the critical points, close to the connectors, close to
the cable yoke and other places. The device must continue drawing zero
line. If there is noise on any lead or the lead fault indicator turns to red,
there is a cable break and you have to change the cable.
Power cord and mains
connection surveillance
Check the outer isolation of the mains cable each time when the device is in
the service station and/or periodically. If there is any demage, change the
cable.
Check the mains socket where the device is used. The wall socket has to be
a grounded type and in good condition. If the earth connection is failed, the
device can detect noisy ECG.
Power cord and charge test
Switch on the device. After a few minutes connect it to the mains via the
power cable. After a few seconds, the yellow CHARGE lamp has to light.
Battery measurement
(detecting shorted cell, or too old
battery)
Charge up the battery leaving the device on the mains for min. two hours.
Disassemble the battery package. Measure the voltage between the red (+)
and black(-) wires using the pins of the connector and pay attention not to
make short circuit, because the fuse in the battery can demage. The voltage
has to be 8 x 1.24V = 9,9V. If the voltage is lower than 9,2V in that case
the battery is too old, or there is a shorted cell inside. In this case change
the battery.

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6.2Checking technical requirements
6.2.1 Leakage current measurement
Leakage current measurement during operation with 253 V examination voltage.
Measurement place
Allowed value / µA /
Between the mains pins and the protective ground
50
Between the mains pins and the patient connection
10
Between the mains pins and the PC SIO connection
10
Between the mains pins and the oxymeter connection
10
Leakage current measurement in case of 1 error with 253 V examination voltage.
Measurement place
Allowed value / µA /
Between the mains pins and the protective ground
100
Between the mains pins and the patient connection
10
Between the mains pins and the PC SIO connection
10
Between the charging adapter connection and the patient connection
10
Between the charging adapter connection and the SIO connection
10
6.2.2 Sensitivity examination and DC tolerance checking
Apply +DC signal according to the table from a ground independent generator to the amplifier’s input (2
mVpp/10Hz sine). DC must be +320,-320 mV. Set amplifier sensitivity to *1 and monitor the lead groups. Start
on-line printing with 50 speed and measure the signal amplitude on the printout.
a. In case of DC= +320 mV
The signal’s amplitude on the examined lead must be 20 mm +/- 3 %.
P1
P2
Examined lead
L
all other
I
R
all other
II
F
all other
III
V1
all other
V1
V2
all other
V2
V3
all other
V3
V4
all other
V4
V5
all other
V5
V6
all other
V6
b. In case of DC= -320 mV
The signal’s amplitude on the examined lead must be 20 mm +/- 3 %.
P1
P2
Examined lead
L
all other
I
R
all other
II
F
all other
III
V1
all other
V1
V2
all other
V2
V3
all other
V3
V4
all other
V4
V5
all other
V5
V6
all other
V6

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6.2.3 Latch-up watch check
Only connect the DC generator to the amplifier input according to the table. The DC level has to be controlled
between 0 and 450 mV. The filter must be turned off.
Connect the patient cable according to the following table and start the channels one-by-one with the channel
selector. On the display check the measurement order quality, the baseline, which can be reset after DC
controlling with the blocking command.
During the examination the device indicates the latch-up watch circuit’s operation with text message. During the
measurement enter the DC values into the table where the text appeared. The comparison levels must be min.
340 mV, max 450mV.
P1
P2
Examined lead
Positive DC (mV)
Negative DC (mV)
L
all other
I
R
all other
II
V1
all other
V1
V2
all other
V2
V3
all other
V3
V4
all other
V4
V5
all other
V5
V6
all other
V6
6.2.4 Measuring noise on the input and baseline checking
Make a 10 seconds long recording with all inputs connected together, at *2 sensitivity, 25 mm/sec speed from all
groups. The filter must be off. Measure the noise and absolute deviation from the baseline on the null-line.
The noise on the input is acceptable if the value of the noise peak-to-peak is not greater than
(0.4 mm+1 pixel)=0.525 mm on any lead. The null-line is acceptable if the deviation from the baseline is less
than 2 mm anywhere on the printout and on the display.

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6.2.5 Checking frequency response
Apply +DC signal onto the amplifier’s input (2000 +/-0.5% µVpp / 150 Hz sine) from a ground independent
generator according to the table. DC must be +320, -320 mV.
The filter must be off.
Connect the patient cable according to the following tables and with the channel selector start the channels one-
by-one, and measure the signal amplitude or during 50 mm/sec *1 printing.
a/ In case of DC = -320 mV
The signal’s amplitude on the examined lead must be min. 1400 µV.
P1
P2
Examined lead
Measured amplitude
L
all other
I
R
all other
II
V1
all other
V1
V2
all other
V2
V3
all other
V3
V4
all other
V4
V5
all other
V5
V6
all other
V6
b. In case of DC = -320 mV
The signal’s amplitude on the examined lead must be min. 1400 µV.
P1
P2
Examined lead
Measured amplitude
L
all other
I
R
all other
II
V1
all other
V1
V2
all other
V2
V3
all other
V3
V4
all other
V4
V5
all other
V5
V6
all other
V6