Service Manual
138 Pages
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Giraffe™ Incubator Service Manual
© 2001-2016 by General Electric Company All rights reserved. General Electric Company reserves the right to make changes in specifications and features shown herein, or discontinue the product described at any time without notice or obligation. Contact your GE Representative for the most current information. Giraffe is a registered trademark owned by Datex-Ohmeda, Inc. GE and GE Monogram are trademarks of General Electric Company. All other company and product names mentioned may be trademarks of the companies with which they are associated.
Table of Contents About this Manual Scope and Intended Users... v Conventions... v User Responsibility... v Important... vi Technical Competence... vi Important Safety Information Warnings... vii Service Language Disclaimer... vi Cautions... xiv Symbol Definitions... xiv Chapter 1: Functional Description 1.1 Control Board... 1-1 1.2 Relay Board... 1-3 1.3 Display Driver Board/EL Display... 1-4 1.4 LED Board... 1-4 1.5 Power Supply... 1-4 1.6 Peripheral Components... 1-4 1.7 Datalink Option... 1-5 1.8 Servo Controlled Oxygen... 1-6 Chapter 2: Service Checkout 2.1 Mechanical Checks... 2-1 2.2 Controller Checks... 2-2 2.3 Humidity Check... 2-3 2.4 Servo Controlled Oxygen Checks... 2-3 2.4.1 Leak Check... 2-3 2.4.2 Pre-use Checkout... 2-3 2.4.3 Supply Valve Leak Test... 2-4 2.5 Scale Checks... 2-4 2.5.1 Visual Inspection... 2-4 2.5.2 Center Weight Check... 2-4 2.5.3 Off Center Weight Check... 2-5 2.6 Accessory Checks... 2-6 2.7 Cable Connections and Mechanical Controls... 2-7 Chapter 3: Calibration and Maintenance 3.1 Maintenance Schedule... 3-1 3.2 Special Tools... 3-1 3.3 System Calibration... 3-3 3.4 Line Voltage Calibration... 3-3 3.5 Humidifier Calibration... 3-4 3.6 Servo Controlled Oxygen Calibration... 3-4 3.7 Scale Calibration... 3-5 3.8 Leakage Current... 3-6 3.9 Ground Resistance Check... 3-6 Chapter 4: Troubleshooting 4.1 Service Screen... 4-1 4.2 Alarm Messages... 4-5 4.3 Error Codes... 4-7 4.4 Troubleshooting Table... 4-12 4.5 Additional Troubleshooting Tips... 4-14 4.6 Servo Controlled Oxygen... 4-16 4.6.1 Servo Controlled Oxygen Service Screen... 4-16 i
Table of Contents
4.6.2 Servo Controlled Oxygen Alarm Messages... 4-17 4.6.3 Servo Controlled Oxygen Troubleshooting Tips... 4-19
Chapter 5: Repair Procedures 5.1 Hood Removal for Replacement... 5-1 5.1.1 Porthole Door Replacement... 5-1 5.2 Uprights and End Caps... 5-2 5.3 Compartment Probe Repairs... 5-3 5.4 Lower Unit Repairs... 5-4 5.4.1 Removing the Chassis Cover with the Storage Door in Place... 5-4 5.4.2 Incubator Fan/Motor/Optical Sensor... 5-5 5.4.3 Cartridge Heater Replacement... 5-5 5.4.4 Elevating Base... 5-6 5.4.5 Chassis Replacement... 5-8 5.4.6 Elevating Footswitch... 5-9 5.4.7 Humidifier Repairs... 5-9 5.5 Bed Tilt Brake Shoe Replacement... 5-12 5.6 Castor Replacement... 5-13 5.7 Controller and Display Module Repairs... 5-13 5.7.1 Display Module... 5-14 5.7.2 Probe Panel... 5-15 5.7.3 Controller Components... 5-15 Control Board... 5-15 Relay Board... 5-16 Solid State Relay... 5-16 Power Supply... 5-16 Battery... 5-17 Toroidal Transformer... 5-17 Circuit Breakers, Power Switches, and Outlets... 5-17 5.8 Servo Controlled Oxygen Service Procedures... 5-17 5.8.1 Installing Oxygen Sensors... 5-17 5.8.2 Replacing the Vent Screen... 5-18 5.8.3 Sensor Housing Repairs... 5-18 5.8.4 Valve Housing Repairs... 5-19 5.8.5 Servo O2 Board Repairs... 5-20 Chapter 6: Illustrated Parts 6.1 Exploded Views... 6-1 6.1.1 Probe Housing, Display Module, and Electrical Enclosure... 6-1 6.1.2 Bed and Side Doors... 6-8 6.1.3 Hood and Compartment Air Probe... 6-13 6.1.4 Chassis... 6-14 6.1.5 Humidifier... 6-18 6.1.6 Elevating Base... 6-20 6.1.7 Hood Latch, Wire Covers, and Uprights... 6-22 6.1.8 Servo Controlled Oxygen... 6-24 6.1.9 Accessory Hangers... 6-28 6.2 Accessories... 6-34 6.3 Labels... 6-35 6.4 PCB layouts... 6-38 6.5 Wiring Diagrams... 6-42 Appendix A Compartment and Skin Probe Characteristics... A-1 Specifications... A-2 RS-232 Serial Data... A-4
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Table of Contents List of Figures
1-1 Block Diagram... 1-2 2-1 Weight Placement Locations... 2-5 2-2 Connections and Controls... 2-7 3-1 Control Board Test Points... 3-2 4-1 First Service Screen... 4-1 4-2 Second Service Screen... 4-2 4-3 Status Menu... 4-2 4-4 Switch Diagnostic Diagram... 4-3 4-5 First Service Screen - Diagnostics... 4-4 4-7 Servo Controlled O2 Service Screen... 4-16
5-1 Hood... 5-1 5-2 Uprights and Endcaps... 5-2 5-3 Compartment Probe... 5-3 5-4 Bed Disassembly... 5-4 5-5 Fan Motor... 5-5 5-6 Heat Sink and Fan... 5-6 5-7 Elevating Base... 5-7 5-8 Chassis Bottom Cover... 5-8 5-9 Humidifier Parts... 5-10 5-10 Replacing the Tilt Brake... 5-12 5-11 Display Module ... 5-14 5-12 Probe Panel... 5-15 5-13 Electronics Enclosure... 5-16 5-14 Installing Sensors... 5-18 5-15 Sensor Housing... 5-19 5-16 Valve Housing... 5-20 6-1 Probe Panel Assembly... 6-1 6-2 Display Module... 6-3 6-3 Electrical Enclosure... 6-5 6-4 Humidifier Transformer and RS-232 Option... 6-7 6-5 Bed ... 6-9 6-6 Side Door (East/West)... 6-11 6-7 Flip Door, Corner Brackets, and Grommets... 6-12 6-8 Compartment Air Probe... 6-13 6-9 Upper Chassis and Heat Sink... 6-15 6-10 Lower Chassis... 6-17 6-11 Humidifier... 6-19 6-12 Base and Elevating Column... 6-21 6-13 Hood Latch and Wire Covers... 6-22 6-14 Uprights and End Caps... 6-23 6-15 Servo Control Oxygen Sensor Housing Assembly... 6-24 6-16 Servo Control Oxygen Valve Housing... 6-25 6-17 Expansion Chamber/Heat Sink Vent... 6-26 6-18 Servo Control Oxygen Cooling Fan... 6-26 6-19 Servo Control Oxygen PC Board... 6-27 6-20 Drainage Hangers and DIN Rail... 6-28 6-21 Storage Drawer... 6-29 6-22 Instrument Shelf... 6-30 6-23 Monitor Shelf... 6-30 6-24 E-Cylinder Holder... 6-31 6-25 Tubing Management Arm... 6-31 iii
Table of Contents 6-26 Dovetail Mount DIN Rail... 6-32 6-27 Silo Support Assembly... 6-32 6-28 Rotating I.V. Pole Assembly... 6-33 6-29 Dovetail Extension... 6-34 6-30 Control Board... 6-38 6-31 Display Driver Roard... 6-39 6-32 Relay Board (Rev. 10 or Higher)... 6-40 6-33 Relay Board (Rev. 9 or Lower)... 6-41 6-34 Wiring Diagram Control Board... 6-42 6-35 Wiring Diagram Elevating Base ... 6-43 6-36 Wiring Diagram Electrical Enclosure... 6-44 6-37 Wiring Diagram Graphics Display... 6-45 6-38 Wiring Diagram Incubator Heater, Relay Board (Rev. 10 or Higher)... 6-46 6-39 Wiring Diagram Incubator Heater, Relay Board (Rev. 9 or Lower)... 6-47 6-40 Wiring Diagram Incubator Fan and Sensor... 6-48 6-41 Wiring Diagram Servo Humidifier, Relay Board (Rev. 10 or Higher)... 6-49 6-42 Wiring Diagram Servo Humidifier, Relay Board (Rev. 9 or Lower)... 6-50 6-43 Wiring Diagram Servo Control Oxygen... 6-51
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About this Manual Scope and Intended Users This service manual describes the repair and maintenance of the Giraffe™ Incubator. The intended users for this service manual are authorized service personnel.
Conventions Various types of pictures or icons are used in this service manual wherever they reinforce the printed message to alert you to potential safety hazards in one of the following ways: Warning: A WARNING statement is used when the possibility of injury to the patient or the operator exists. Caution: A CAUTION statement is used when the possibility of damage to the equipment exists. SENSITIVE TO ELECTROSTATIC DISCHARGE CAUTION An Electrostatic Discharge (ESD) Susceptibility symbol is displayed to alert service personnel that the part(s) are sensitive to electrostatic discharge and that static control procedures must be used to prevent damage to the equipment. NOTE: A note provides additional information to clarify a point in the text. IMPORTANT: An Important statement is similar to a note, but is used for greater emphasis.
User Responsibility This Product will perform in conformity with the description thereof contained in this service manual and accompanying labels and/or inserts, when assembled, operated, maintained and repaired in accordance with the instructions provided. This Product must be checked periodically. A defective Product should not be used. Parts that are broken, missing, plainly worn, distorted or contaminated should be replaced immediately. Should such repair or replacement become necessary, GE Healthcare recommends that a telephone or written request for service advice be made to the nearest GE Healthcare Regional Service Center. This Product or any of its parts should not be repaired other than in accordance with written instructions provided by GE Healthcare and by GE Healthcare trained personnel. The Product must not be altered without GE Healthcare’s prior written approval. The user of this Product shall have the sole responsibility for any malfunction that results from improper use, faulty maintenance, improper repair, damage or alteration by anyone other than GE Healthcare.
v
About this Manual Important The information contained in this service manual pertains only to those models of products which are marketed by GE Healthcare as of the effective date of this manual or the latest revision thereof. This service manual was prepared for exclusive use by GE Healthcare service personnel in light of their training and experience as well as the availability to them of parts, proper tools and test equipment. Consequently, GE Healthcare provides this service manual to its customers purely as a business convenience and for the customer’s general information only without warranty of the results with respect to any application of such information. Furthermore, because of the wide variety of circumstances under which maintenance and repair activities may be performed and the unique nature of each individual’s own experience, capacity, and qualifications, the fact that a customer has received such information from GE Healthcare does not imply in anyway that GE Healthcare deems said individual to be qualified to perform any such maintenance or repair service. Moreover, it should not be assumed that every acceptable test and safety procedure or method, precaution, tool, equipment or device is referred to within, or that abnormal or unusual circumstances may not warrant or suggest different or additional procedures or requirements. This manual is subject to periodic review, update and revision. Customers are cautioned to obtain and consult the latest revision before undertaking any service of the equipment. Caution: Servicing of this product in accordance with this service manual should never be undertaken in the absence of proper tools, test equipment and the most recent revision to this service manual which is clearly and thoroughly understood.
Technical Competence The procedures described in this service manual should be performed by trained and authorized personnel only. Maintenance should only be undertaken by competent individuals who have a general knowledge of and experience with devices of this nature. No repairs should ever be undertaken or attempted by anyone not having such qualifications. Genuine replacement parts manufactured or sold by GE Healthcare must be used for all repairs. Read completely through each step in every procedure before starting the procedure; any exceptions may result in a failure to properly and safely complete the attempted procedure.
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Important Safety Informaton Warnings Warning: Before using the Incubator, read through this entire manual. As with all medical equipment, attempting to use this device without a thorough understanding of its operation may result in patient or user injury. This device should only be operated by personnel trained in its operation under the direction of qualified medical personnel familiar with the risks and benefits of this type of device. Additional precautions specific to certain procedures are found in the text of this manual. Warning: Complete the Pre-use Checkout chapter of the Operation and Maintenance manual before putting the unit into operation. If the Incubator fails any portion of the checkout procedure it must be removed from use and repaired. Warning: Do not use the Incubator in the presence of flammable anesthetics; an explosion hazard exists under these conditions. Warning: Always disconnect the power before performing service or maintenance procedures detailed in this manual. Apply power only if you are specifically instructed to do so as part of the procedure. Warning: Thoroughly air dry the Incubator after cleaning it with flammable agents. Small amounts of flammable agents, such as ether, alcohol or similar cleaning solvents left in the Incubator can cause a fire. Warning: The user or service staff should dispose all the waste properly as per federal, state, and local waste disposal regulations. Improper disposal could result in personal injury and environmental impact.
Service Language Disclaimer Warning: This service manual is available in English only. (EN)
• • •
If a customer’s service provider requires a language other than English, it is the customer’s responsibility to provide translation services. Do not attempt to service the equipment unless this service manual has been consulted and is understood. Failure to heed this warning may result in injury to the service provider, operator, or patient from electric shock, mechanical hazards, or other hazards.
ПРЕДУПРЕЖДЕНИЕ Това упътване за работа е налично само на английски език.
(BG)
• • •
Ако доставчикът на услугата на клиента изиска друг език, задължение на клиента е да осигури превод. Не използвайте оборудването, преди да сте се консултирали и разбрали упътването за работа. Неспазването на това предупреждение може да доведе до нараняване на доставчика на услугата, оператора или пациентa в резултат на токов удар, механична или друга опасност.
vii
Important Safety Information Cautions
37 c 37 c 37 c 37 c
Caution: Only competent individuals trained in the repair of this equipment should attempt to service it as detailed in this manual.
Temp alarm
Caution: Tempinformation alarm for more extensive repairs is included in the service manual solely for Detailed the convenience of users having proper knowledge, tools and test equipment, and for service Temp alarmtrained by GE Healthcare. representatives
Heater Temp alarm Heater Heater
Heater Airflow curtain Symbol Definitions Airflow curtain This section identifies the symbols that are displayed on the Giraffe Incubator:
37 c
Airflow curtain Fan Description Airflow curtain Fan Temp alarm
37 c
Fan Temp alarm
Symbol
Consult accompanying documents.
Fan
Heater Canopy up / down (usedmounting in conjunction with up/down arrows) Lower the elevating base before accessories. Canopy Heater up / down (used in conjunction with up/down arrows)
37 c
Canopy up / down (used in conjunction with up/down arrows) Temperature Alarm Temp alarm Airflow curtain Canopy up / down (used in conjunction with up/down arrows) Airflow curtain Airflow Curtain
Heater Environmental Probe
Environmental Probe Fan
Fan
Environmental Probe Fan Airflow Scale curtain Probe Environmental Environmental Probe Scale
2 2 2 2
Canopy up / down (used in conjunction with up/down arrows) Scale Scale Fan Canopy up / down (used in conjunction with up/down arrows) Scale Patient O2 Patient O2 Patient Oxygen Patient O2 Canopy up / down (used in conjunction with up/down arrows) Alarm Alarm SilenceSilence Environmental Probe Patient O2
Alarm Silence
Environmental Probe
xiv
Alarm Silence Patient Scale Silence Alarm
Patient O2
2
Used on Giraffe Humidifier Reservoir Symbol
Important Safety Informaton
Description
Alarm Silence
Alarm Silence (China) Ground Used on all electrical equipment
Patient
Patient
MAX
Ground Used on all electrical equipment
Max water level for humidifier
Used on Giraffe Humidifier Reservoir
Protective Ground
Ground Ground Used on all electrical equipment Used on all electrical equipment
Ground Used on all electrical equipment
Used on Giraffe Humidifier Reservoir
Used on Giraffe Humidifier Reservoir Used on Giraffe Humidifier Reservoir
Opening Giraffe Humidifier Reservoir
MAX
MAX
Max water level for humidifier
MAX MAX
Max water level for humidifier Max water level for humidifier
Max water level for humidifier
Power disconnect
Maximum Water Level for Humidifier
Used on Giraffe Humidifier Reservoir
Power disconnect
Power disconnect Power disconnect
Power Disconnect
Power disconnect
22 Kg MAX.
Kg 222222MAX. Kg Kg MAX. MAX. 22 Kg
Maximum weight (of accessories on rail)
Maximum Weight Maximum weight (of accessories on rail)
Maximum weight (of accessories on rail) Maximum weight (of accessories on rail)
MAX.
Maximum weight (of accessories on rail) Used on Giraffe OB heater head, Caution: Hot Surface Used on Giraffe OB heater head, humidifier
Caution: Hot surface Caution: Hot surface Caution: Hot surface
MAX
Used on Giraffe OB heater head, humidifier humidifier
Set up Used screen on Giraffe OB heater head, humidifier Max water level for humidifier Used on Giraffe OB heater head,
Caution: Hot surface Setup Screen
Caution: Hot surface
humidifier
Power disconnect
22 Kg MAX.
Maximum weight (of accessories on rail)
xv
Important Safety Information
xvi
Chapter 1: Functional Description This functional description is divided into four sections representing each of the four boards. The reader should also reference the block diagram and wiring diagram when studying this section.
1.1 Control Board The Intel 80C188EC microcontroller is an enhanced X86 processor with many on-board peripheral features, such as a interrupt controller, DMA controller, peripheral chip select driver, programmable timers, etc. The two programmable timers are used to control the two heaters (bed and radiant). The input to these timers is line frequency. This allows the control signal to be synchronized with the line frequency to better control the zerocrossing solid state relays. The on-board interrupt controller has several interrupts: analog-to-digital converter (ADC) conversion ready signal, overtemperature comparator output, watchdog output, power fail signal, and module interrupt signal from the system data bus. The microcontroller external bus is a multiplexed address and data bus. The system memory consists of a programmable read-only memory (PROM) and static random access memory (SRAM). The EEPROM is used for calibration values and infrequently changing variables. This memory holds the data even after power is turned off. The RS-485 integrated circuit converts the RS-232 TTL signals from the microcontroller to RS-485 signals for the bus. This bus is the main communications bus from the control board to all other boards with processors. There are two isolation transceivers used to isolate the circuits powered by +5V and the circuits powered by +5VSTBY (battery backup). The board contains a 16 channel multiplexer. There are seven temperature measurement channels. These channels measure the two patient probes with two thermistors each, the two air temperature thermistors used for display and control, and an additional thermistor used to measure the heat sink temperature. Additional channels include the humidity sensor (RHIN), LINE COMP & LINE COMP2, 5 Volts, Motor current, Vthref, VDAC, and 1.2Vind. Attached to the environmental probe connection is the relative humidity signal conditioning circuitry. The 1V reference that is used for the analog circuitry is also the maximum input voltage and the offset voltage for the ADC. This yields a purely ratiometric system. The overtemperature circuit compares the air temperature to a reference level, generates an interrupt, and turns off the heat if the air temperature is higher than the reference level. The overtemperature circuit requires varying its voltage levels to accommodate various thermistor measurements. This is because the calibration is digital (no potentiometer). The watchdog circuitry monitors the 80C188 microprocessor, and monitors the +5V and +5VSTBY voltages. It generates the interrupt signal and power failure signal to the 80C188 microprocessors. The audio circuit includes a 8752 microcontroller that reads a wavetable located in a PROM and sends the table to a digital audio circuit and amplifier. The high priority (HP) and other alarm signal lines select an output at the correct frequencies. Three OR gates are combined to generate the error signal. The inputs to the circuit are overtemperature, power failure, and system failure. This circuit generates an error signal that turns off the heater and sounds the HP alarm. This circuit is independent of the microcontroller.
1-1
Chapter 1: Functional Description
Figure 1-1 Block Diagram 1-2
Chapter 1: Functional Description 1.2 Relay Board The Relay Board includes 2 safety relays, which close to supply mains power to the heater and motor circuits. Safety relay 1 is wired in series with the primary coil of the isolation transformer for the incubator heater. Safety relay 2 closes the mains supply to the humidifier isolation transformer and the transformer for the e-base motor. Control signals for the two relays originate on the Control Board. The Relay Board interfaces the DC Control signal to the chassis mounted solid-state relay (SSR), which controls the incubator heater. The Control signals for the heater SSR originates on the Control Board. The Relay Board includes a SSR for the humidifier. The SSR output is wired in series with the humidifier heater. The humidifier SSR control signal originates on the Control Board. There is one current sense circuit for the incubator and an additional one for the humidifier heater. These circuits consist of a small signal transformer that produces a current proportional to the current through the heater circuits. The current is rectified and measured. The subsequent comparator then generates a digital level based on a specified current level. This results in a signal to the Control Board representing the state of the heater (on or off). The line compensation circuit consists of a signal transformer connected to the mains voltage. The secondary of this transformer feeds a full wave rectifier and capacitor. The resulting DC voltage is proportional to mains voltage, and it is measured on the Control Board. The line frequency circuit consists of a full wave rectifier and a comparator. This circuit generates a digital pulse with frequency twice that of the line frequency (50 or 60 Hz). The output signal is provide to the Control Board. The Relay Board provides the +5v standby power supply to the entire Giraffe system. A +5V regulator generates the +5V standby from the diode OR combination of the system +12V power supply or the backup battery. If there is no mains power, then +12v is not present, and the battery will generate the +5V standby. When +12V is present, the battery is biased out of the circuit with the diode and is merely being trickle charged though a resistor. The motor driver circuit turns the DC motor coils in the incubator airflow fan motor on and off based on feedback from the hall effect position sensors. This integrated circuit can also vary the speed and brake the motor based on input signals from the Control Board. The airflow sensor consists of an opto-coupler that outputs a clocking pulse proportional to the fan movement. The signal is AC coupled to eliminate offset voltages and drifts. The resulting pulse is half wave rectified and stored in a capacitor to yield a DC voltage proportional to the fan speed. If the fan stops or there is no fan, this DC voltage becomes zero. The output signal is provide to the Control Board to indicate proper airflow motor operation. The elevating base circuit consists of a series of relays that apply voltage to the elevating base motor. The ebase motor is always driven at 30 volts. The motor current sense circuit consists of a small signal transformer that produces a current proportional to the motor current. The transformer output current is converted to a voltage and filtered. An output voltage indicative of the motor current amplitude is provided to the Control Board. A subsequent comparator then generates a digital level based on a specified current level. This results in a signal to the Control Board indicating whether or not the e-base motor is stalled. The Relay Board interfaces the user and system status input switch signals to the Control Board. Switch signals include, e-base activation, humidifier reservoir, and water level status.
1-3
Chapter 1: Functional Description 1.3 Display Driver Board/EL Display The Display Driver board contains the same Intel microcontroller as the Control board. The processor on the display board is used to control the EL display contents and monitor user inputs received from the membrane switch panel and rotary encoder knob. There are two groups of digital inputs: membrane switch panel and rotary encoder knob. The membrane switches are pulled high; pressing the switch grounds the input. The encoder also has a switch, and two optically isolated lines that pulse out of phase with each other. The number of pulses represents the number of steps the knob rotates. The phase of the pulses represents the direction of the knob rotation. The display board system memory consists of a programmable read-only memory (PROM) and static random access memory (SRAM). The RS-485 integrated circuit converts the RS-232 TTL signals from the microcontroller to RS-485 signals for the bus. The timekeeping RAM has a battery integrated into the chip so that the time and date run are kept current even with the power off. The battery has a minimum life of 10 years. The graphics controller is an S-MOS VGA controller. The graphics controller interfaces the data from the video RAM to the EL display. The controller also synchronizes the display using a horizontal pulse (LP) and a vertical pulse for the whole display frame (YD). The controller handshakes with the 80C188 using the READY line to eliminate any lost data during display refreshes.
1.4 LED Board The LED Board contains five display banks and two display drivers. One of the display drivers controls the patient temperature and air temperature display banks. The other driver controls the patient set temperature, air set temperature, warmer bar graph, and the mode and override indicators. This allows the two large displays (patient and air temperature) to be multiplexed at a slower rate than the other LEDs. This results in brighter large displays. Each driver has a brightness potentiometer that is preset at the factory and should not be adjusted in the field.
1.5 Power Supply The universal input switching power supply converts the line voltage to +5V DC and +12V DC. This supply can source up to 75 watts. The 5 volts powers the electronics and the 12 volts is used by the EL display and for future boards.
1.6 Peripheral Components There are several peripheral components. The isolation transformer isolates the overhead heater from the line voltage. The toroidal transformer bucks the line voltage to the range of the elevating base and the canopy lift drive system. The humidifier isolation transformer isolates the humidifier heater from the line voltage. The solid state relays mounted to the chassis are used to control the bed heater.
1-4
Chapter 1: Functional Description 1.7 DataLink Option The DataLink option allows direct output of serial data to various remote monitoring systems, such as a computer or commercial RS-232 monitor. The DataLink option board contains the electronic circuitry necessary to provide a 2500 VRMS isolated serial interface to meet the logic levels specified by EIA RS-232D and CCITTV.28. The MAX250 and MAX251 (U1 and U2), together with two 6N136 optocouplers and transformer TR1, form an isolated RS-232 transmitter and receiver. The MAX250 connects to the non-isolated or “logic” side of the interface, translating logic signals to and from the optocouplers, while the MAX251 resides on the isolated or “cable” side, translating data between the optocouplers and RS-232 line drivers and receivers. In addition to the optocoupler drivers and receivers, the MAX250 also contains isolation transformer drive circuitry which supplies power to the isolated side of the interface, and the MAX251. The transmit signal is input to the MAX250 driver (U1 pin 4) whose output (U1 pin 3) drives optocoupler U4. The optocoupler output (U4 pin 6) is then fed into the MAX251 driver (U2 pin 3). The output of the MAX251 driver (U2 pin 12) is at the logic levels conforming to EIA RS-232D and CCITTV.28. Conversely, the receive signal enters the MAX251 driver (U2 pin 10) and is stepped down to CMOS/TTL levels at U2 pin 5. This logic level drives optoisolator input (U3 pin 3) whose output is fed into U1 pin 10. The output (U1 pin 9) signal is then available to the control printed circuit board. A slide switch SW1 is used as a “self test” for the RS-232 interface. In the closed position, the J30-1 transmit signal is sent through the MAX250/MAX251 transmitter and back into the receiver portions. The signal can be read at J30-2 and verified to be correct. Any external cable connection must be removed for this self test to function. CR1 and CR2 provide transient protection for MAX251. In normal operation SW1 should be in the open (OFF) position. The nurse call signal is input at J30-5 as a TTL logic level. In the “no alarm” state, this signal is a logic high, which turns on Darlington Q1, energizing relay K1. This results in contact closure between J31-1 and J31-2. In the “alarm” state, J30-5 is a logic low, which turns off Q1, de-energizes K1 and results in contact closure between J31-2 and J31-3. K1 provides 2500 VRMS isolation between the relay coil inputs and contact outputs.
1-5
Chapter 1: Functional Description 1.8 Servo Controlled Oxygen Option The Giraffe Servo Control Oxygen System consists of an oxygen sensing circuit, Servo Oxygen circuit board, and an oxygen delivery system. The sensing circuit is located beneath the bed and consists of a pair of fuel cell oxygen sensors, a three-way solenoid calibration valve, and a calibration fan. In normal operation the calibration valve is closed and allows the Giraffe fan to circulate gas from the infant compartment across the sensors. The unit must be calibrated at least every 24 hours when servo oxygen is in use. After 24 hours have elapsed the system prompts the user to perform calibration. Once the operator initiates calibration, the calibration valve opens and the calibration fan is turned on. This draws ambient air across the sensors until a stable reading is obtained. This 21% oxygen reference value is then used to calibrate the measuring algorithm. After calibration 100% oxygen is briefly delivered to the system to ensure there are no occlusions. When calibration is complete the unit will resume controlling oxygen based on the last set point. The system must have two sensors present to operate. One sensor is always used for control and the other is used for a redundant check and display. The sensors generate a voltage of about 40 millivolts at 21% oxygen concentration and about 200 millivolts at 100% oxygen concentration. The voltage is directly proportional to the concentration of oxygen. Humidity and temperature sensors located in the sensor plug are used for voltage compensation. A fan mounted to the sensor-housing door is activated when the temperature reaches 50 degrees C. This fan circulates air to keep the sensors below the maximum allowable operating temperature, about 55 degrees C. The Servo O2 board is located in the Giraffe controller. The microcontroller and integrated EPROM on the board perform the following: Convert sensor output from analog to digital Activates oxygen alarm conditions. Two-way communications via 485 bus with the Giraffe control board. Controls the calibration valve to select calibration mode. Controls the two supply valves to maintain the desired oxygen set point. Opens the safety relay, which removes power to the two-way valve and the supply valves in case of a system failure. The oxygen delivery system consists of two solenoid supply valves, and a regulator assembly. The preset regulator regulates the oxygen supply to 50 psi (345 kPa). Two supply valves, controlled by the Servo Oxygen board, control flow to the infant compartment. Both valves are opened until the measured level gets close to the desired set point then one valve is closed. One valve is then cycled on and off as needed to maintain the desired oxygen levels in the infant compartment. The valve selected is alternated so both valves cycle about the same number of times. There are 2 fuses between the Servo O2 board and the supply valves that prevent high current from the board entering the valve housing should a short occur in the supply valves.
1-6
Chapter 2: Service Checkout Warning: Do not perform the preoperative checkout procedure while the patient occupies the unit. Warning: Complete the preoperative checkout procedure section of this manual before putting the unit into operation. If the equipment fails any portion of the checkout procedure, it must be removed from use and repaired.
2.1 Mechanical Checks 1.
Disconnect the power cord for the mechanical portion of the preoperative checkout procedure.
2.
Examine the power cord for any signs of damage. Replace the cord if damage is evident.
3.
Check that both plug retaining brackets are in place.
4.
Examine the unit overall for any damaged or missing parts.
5.
Check that all the casters are in firm contact with the floor and that the unit is stable. Lock the caster brakes and check that they hold the unit in place. Release the brakes and check that the unit moves smoothly.
6.
Check the operation of the side doors. Open the doors and check that they swing all the way down and hang perpendicular to the bed. Check that the doors are securely attached to the unit and that the hinge pins are properly seated. Check that the inner walls are securely fastened to the doors. Close the doors and check that the latches hold the doors securely shut. The orange latch open indicators should not be visible when the latches are engaged. Check that the hood is in the locked position.
7.
Check the tubing acces door at the top of the ventilator slot in the back wall. It should flip up easily and smoothly, and stay in position anywhere on its travel path.
8.
Check the portholes. Open the portholes by pressing on the latch. The cover should swing open. Close the porthole and check that the latch holds the cover securely shut and that the cover seals tightly against the porthole gasket. Check that all the porthole seals are in place and are in good condition.
9.
If the unit is equipped with an iris porthole, check the iris is installed and in good condition. Check that the iris tightens when it is rotated.
10. Check that the tubing access covers in the four bed corners and the large slot grommet at the head of the bed are in place and are in good condition. 11. Check the operation of the bed. The bed should rotate easily without binding. If the bed is properly seated and locked in place, the mattress should be level. With the bed rotated back into the straight position, check to see that the bed platform extends and stops when it is pulled out on either side. Check the operation of the bed tilt mechanism. Squeeze the tilt control and push down on the foot of the bed. The head of the bed should raise easily, and should stay in position at any angle along its tilt path when the tilt control is released. Push down on the head of the bed. The foot of the bed should raise easily, and should stay in position at any angle along its tilt path when you the tilt control is released. 12. Check the operation of the hood lock. Release the lock and raise the hood. Make sure it locks in the open position. Release the lock and lower the hood. Make sure it locks in the closed position.
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Chapter 2: Service Checkout 2.2 Controller Checks Warning: Do not use the Incubator in the presence of flammable anesthetics; an explosion hazard exists under these conditions.. 1.
Connect the incubator power cord to a properly rated outlet.
2.
Connect the patient probe to jack 1 on the probe panel.
3.
Switch on the power at the mains switch on the back of the unit, and at the standby switch on the probe panel, while holding in the override button (>37) on the display during power up until the software revision screen appears. Release the button and the first service screen will appear.
4.
Scroll to “Down” and select it to bring up the second service screen. Select Status to see Status screen. Check status of the software self tests. These include: heater on (INCHTRON), ) heater off (IHTROFF), humidifier heater on (RHHTR), remote monitoring data stream (RS232LOOP), incubator fan on (FANON), and incubator fan off (FANOFF). All test should say PASS except RS232 LOOP. If the RS232 option is not installed RS232LOOP will display N/A. To test the circuit if the option is installed, short pins 2 & 3 on the 9 pin connector on the back of the electrical enclosure.
5.
Using the standby switch turn off the unit, then turn it back on. Verify the following: All the displays and indicators light The software revision appears The prompt tone begins Note: If the unit has been used in the last 2 hours, the patient history query appears.
6.
Adjust the set temperature to silence the prompt tone.
7.
Check the patient probe. If the probe is below 30 C, the display will show -L-. Warm it by placing it between your fingers, and verify that the baby temperature reading increases.
8.
Unplug the patient probe and check that both visual and audio alarms trigger in the Baby control mode.
9.
If so equipped, check the operation of the bed elevating system. Raise and lower the bed along its entire travel range, checking that the mechanism operates smoothly. Check that the pedals on both sides of the unit raise and lower the bed.
10. Check the power failure alarm and the battery backed up memory. Make note of the current control mode and temperature settings and wait one minute, then unplug the Incubator from the wall outlet. An alarm should sound and the power failure indicator should light. Wait one to two minutes and plug the Incubator back in. Verify that the alarm cancels and that the Incubator returns to the same control mode and temperature settings it displayed before the power interruption. Note: A fully charged battery should supply the power failure alarm for approximately 10 minutes. If the alarm is tested for the full 10 minutes the Incubator must be run at least two hours to recharge the battery before it is used with a patient. Total recharge time is 8 to 10 hours. 12. Perform the Leakage Current and Ground Resistance checks in Chapter 3 of this manual.
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