GE Cardiocap 5 Service Manual

							
Measurement Parameters 
 
Figure 6-25. Signal processing 
 
Figure 6-26. Control logic 
 
Figure 6-27. Calibration data stored in EEPROM 
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Cardiocap/5 Technical Reference Manual 
6.7 NMT components 
6.7.1 NMT board 
The NMT circuit board consists of the following functional sections: 
• Constant current stimulator. 
• Measuring electronics for the EMG signals. 
• Microprocessor for stimulation and measurement control, and for counting measurement results. 
• Serial communication. 
The serial bus speed is 500 kbps and the bus itself is half duplex (data can be transferred in both 
directions but only one way at a time). 
Serial communication 
 
Figure 6-28. NMT serial communication and opto isolation 
Stimulator 
The constant current stimulator generates pulses whose amplitude is independent of the load. The 
main components of the stimulator are a transformer, a capacitor and a transistor. The transformer 
produces a high voltage which charges the capacitor and the transistor adjusts the pulse width and 
amplitude of the current. 
 
Figure 6-29. NMT stimulator block diagram 
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Measurement Parameters 
6.7.2 Front panel connector (NMT) 
   
NMT connector Pin No. Signal 
 
1 
2 
3 
4 
5 
6 
7 
8 
9 
10 
EMG signal + 
EMG signal – 
Not used 
Stimulus + 
Stimulus – 
Ground 
Not connected 
Sensor identification 
+5 V 
Mechanical signal 
6.7.3 Module bus connector 
 
   
Pin No. I/O Signal 
1 I RESET_RS485 
2 I –15 VDC 
3 I +15 VDIRTY 
4 I +15 VDC 
5 I/O –DATA_RS485 
6 I/O DATA_RS485 
7 – Ground & Shield 
8 I –RESET_RS485 
9 I CTSB 
10 O RTSB 
11 I RXDB 
12 O TXDB 
13 – Ground & Shield 
14 I +32 VDIRTY 
15 I GroundDIRTY 
16 I CTSC 
17 O RTSC 
18 I RXDC 
19 O TXDC 
20 – ON/STANDBY 
21 – PWM_ECG 
22 – RXDD_RS232 
23 – TXDD_RS232 
24 I +5 VDC 
25 I +5 VDC 
   
 
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Cardiocap/5 Technical Reference Manual 
 
 
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Contents 
Chapter 7. Service Procedures  
7.1 General service information..................................................7-1 
7.2 Monitor software installation................................................7-1 
“Cold start” instructions........................................................................\
.....7-1 
“Warm start” instructions........................................................................\
...7-1 
7.3 Replacement procedures......................................................7-2 
7.3.1 Disassembling the frame assembly.............................................................7-2 
7.3.2 Mother board removal........................................................................\
.......7-2 
7.3.3 ECG, NIBP, and STP board replacement......................................................7-3 
NESTPR unit removal........................................................................\
.........7-3 
ECG board replacement........................................................................\
.....7-3 
NIBP board replacement........................................................................\
....7-3 
STP board replacement........................................................................\
......7-3 
7.3.4 Backplate unit removal........................................................................\
......7-3 
7.3.5 Gas unit CPU board, pump, and fan replacement.........................................7-4 
Airway-gas unit removal........................................................................\
.....7-4 
Gas unit CPU board replacement................................................................7-4 
Pump unit replacement........................................................................\
......7-4 
Fan replacement........................................................................\
...............7-4 
7.3.6 AC/DC unit replacement........................................................................\
....7-5 
7.3.7 DC/DC board replacement........................................................................\
.7-5 
7.3.8 Recorder unit replacement........................................................................\
.7-5 
7.3.9 Inverter board and Backlight board replacement..........................................7-5 
Inverter board replacement........................................................................\
7-5 
7.3.10 CPU battery replacement........................................................................\
...7-6 
7.3.11 CPU board replacement........................................................................\
.....7-7 
7.3.12 LCD display, LCD display backlight, and keyboard replacement....................7-7 
LCD display removal........................................................................\
..........7-7 
Replacing LCD display backlights...............................................................7-7 
Replacing the keyboard........................................................................\
.....7-7 
7.3.13 Enhanced pulse oximetry (N-XOSAT) or SpO2 interface board replacement.....7-8 
7.3.14 Nellcor pulse oximetry (N-XNSAT) or SpO2 interface board replacement..........7-9 
7.3.15 NMT board or NMT cable assembly replacement..........................................7-9 
7.4 Adjustments and calibration...............................................7-10 
7.4.1 Pressure safety-level detection OFFSET.................................................7-10 
7.4.2 NIBP calibration check........................................................................\
.....7-11 
Checking the primary pressure channel calibration.....................................7-11 
Using a manometer to check NIBP calibration............................................7-11 
7.4.3 NIBP calibration........................................................................\
..............7-12 
7.4.4 Temperature calibration........................................................................\
...7-13 
7.4.5 Invasive pressure calibration....................................................................7-13 
7.4.6 General checks for gas system components..............................................7-14 
  
						

							
Cardiocap/5 Technical Reference Manual 
Oxygen measuring (OM) unit ..................................................................... 7-14 
TPX measurin g unit ........................................................................\
.......... 7-14 
PVX measurin g unit........................................................................\
.......... 7-14 
Gas unit CPU  board........................................................................\
.......... 7-14 
7.4.7 Gas sampling system  leak test .................................................................. 7-15 
7.4.8 Flow rate checks and adjustments ............................................................ 7-15 
Flow rate checks ........................................................................\
.............. 7-15 
Flow rate ad justment.......................................................................\
......... 7-15 
7.4.9 Spirometry leakage test  and calibration..................................................... 7-16 
Spirometry leakage test........................................................................\
.... 7-16 
Flow calibration ........................................................................\
............... 7-16 
7.4.10 Gas calibration ........................................................................\
................ 7-16 
Calibration gas regula tor flow check .......................................................... 7-16 
Gas calibration ........................................................................\
................ 7-17 
Calibration adju stments ........................................................................\
... 7-18 
Autozeroing intervals ........................................................................\
........ 7-18 
Table of Figures  
Figure 7-1. CPU batte ry replacement ........................................................................\
........ 7-6 
Figure 7-2. SpO2 interface board ........................................................................\
.............. 7-8 
Figure 7-3. NI BP board ........................................................................\
.......................... 7-10 
Figure 7-4. Calibr ation switch ........................................................................\
................. 7-12 
Figure 7-5. Attachin g the regulator........................................................................\
.......... 7-17 
Figure 7-6. Connecting a sampli ng line and feeding gas................................................... 7-17 
 
  
						

							
Service Procedures 
7. SERVICE PROCEDURES 
7.1 General service information 
Field service of the Cardiocap/5 monitor is limited to replacing faulty circuit boards, mechanical parts, 
or a real-time clock battery. Some boards may be returned to GE Healthcare for exchange. 
For service advice from GE Healthcare, please provide the unit serial number, full type designation, 
and a detailed fault description.  
CAUTION: Only trained personnel with the appropriate tools and equipment shall perform the tests 
and repairs outlined in this chapter. Unauthorized service may void warranty of the unit. 
CAUTION: Electrostatic discharge through the PC boards may damage the components. Before 
replacing PC boards, wear a static-control wrist strap. Handle all PC boards by their non-conductive 
edges and use anti-static containers when transporting them. 
CAUTION: When reassembling the monitor, make sure all cables and tubing are reconnected properly 
and are not pinched between other components. 
7.2 Monitor software installation 
“Cold start” instructions 
Follow these installation instructions if the monitor has been off for more than 15 minutes: 
1. Insert the service software PC card into the data card slot closest to the display. 
2. Power on the monitor. Both LEDs illuminate and the screen remains blank for approximately two 
minutes while loading. 
3. When the normal monitoring screen is displayed, remove the card. 
4. Perform the factory reset. 
“Warm start” instructions 
Follow these instructions if the monitor has been off for less than 15 minutes: 
1. Insert the service software PC card into the data card slot closest to the display. 
2. To start the software loading you need to perform the factory reset. Push the ComWheel and 
select: 
Install/Service (16-4-34) 
Service (26-23-8) 
Monitor 
Factory Reset 
Both LEDs illuminate and the screen remains blank for approximately two minutes while loading. 
3. When the normal monitoring screen is displayed, remove the PC card. 
4. Perform the factory reset. 
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Cardiocap/5 Technical Reference Manual 
7.3 Replacement procedures 
NOTE:  Reassembly is essentially the reverse of disassembly. When reassembling the unit, make sure 
that the cables and tubes, if any, are not pinched between the boards. 
Tools 
• Screwdriver (pozidrive) 
• Hexagon driver (3.0 mm) 
• Pliers 
• Cable tie 
7.3.1 Disassembling the frame assembly 
1. Remove the 4 hexagon and 13 pozidrive screws that hold the back cover. 
2. To pull the front-cover unit apart from the inner-parts unit, remove the 4 screws that hold the front-
cover unit and the inner-parts unit together.  

						

							
Service Procedures 
7.3.3 ECG, NIBP, and STP board replacement 
The NESTPR unit must be removed before you can replace the ECG, NIBP, or STP boards. 
NESTPR unit removal 
You may separate the display from the frame to gain better access to the NESTPR unit, but it is not 
necessary. To remove the unit without separating the display: 
1. Disconnect the 5 patient-connector cables from the front panel. 
Important: For reassembly, note the connection of temperature cable T1 (black wires) and, for 
monitors with two temperature measurements, temperature cable T2 (yellow wires). T2 is not 
connected for monitors that have only one temperature measurement. 
2. Disconnect the NIBP tubes from the module. 
NOTE: The foremost NIBP tube is connected to the upper NIBP connector. 
3. Carefully lift the unit up. 
ECG board replacement 
1. Remove 4 screws from the ECG board and disconnect the flat cable from the STP board. 
2. Detach the ECG board. 
NIBP board replacement 
1. To access the NIBP board, remove the ECG board. 
2. Remove 4 screws from the corners of the NIBP unit. 
3. Disconnect the ribbon cable from the EST board. 
4. Disconnect the NIBP tubes from the adapter. 
NOTE: Notice the correct tube connections; lower one to the inner one.  
5. Pull the NIBP board carefully out. 
STP board replacement 
1. Detach the ECG board. 
2. Disconnect NIBP tubes from the both sides of the plastic strut. Remove the plastic strut carefully 
from the NESTPR unit’s frame. 
3. Disconnect the ribbon cable from the STP board 
4. Remove 4 screws from the corners of the STP board and detach the STP board. 
7.3.4 Backplate unit removal 
The backplate unit contains the fan, speaker, and I/O board  
1. Remove the 3 screws that hold the backplate unit to the AC/DC unit. 
2. Push the backplate unit forward and bend the retainers in both sides to loosen the unit. 
3. Carefully pull out the backplate unit. 
4. Disconnect the CPU–NET board cable from the I/O board. 
5. Disconnect the fan power cable from the DC/DC board. 
6. To remove the sample gas outlet tube, unfasten the lock washer from the gas outlet connector 
(X6) and pry the connector out of the cover. 
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Cardiocap/5 Technical Reference Manual 
7.3.5 Gas unit CPU board, pump, and fan replacement 
The airway gas unit must be removed before you can replace the gas unit CPU board, the pump, or the 
fan. 
Airway-gas unit removal 
1. Move the backplate unit out of the way to access the airway gas unit (see Backplate unit removal). 
2. Unfasten the 3 screws and washers that hold the locking chock and remove the chock. 
3. If installed, disconnect the hook-and-loop strap. 
4. Disconnect the 2 tubes from the rear of the airway gas unit. 
5. Grip the airway gas unit and pull it out sideways. 
Gas unit CPU board replacement 
1. Remove 4 screws from the corners of the OM board. 
2. Disconnect the following cables from the gas unit CPU board: