CareFusion IVAC P6000, Техническое и сервисное руководство

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Circuit Descriptions
P7000, P6000, TIVA, TCI & TIVA 41/106 1000SM00012 Issue 8
Module Overview Functional Description
The IVAC® Syringe Pumps are designed to be serviced generally to major assembly level.
The circuitry within the pump is contained on three printed circuit boards (PCBs): Control PCB, Display PCB and Power
Supply PCB. Mark I pump models also have an Interface PCB fitted. In addition, two flexible printed circuits are utilised to
hold the optical sensors and to provide the necessary interconnects to the moving parts of the pump.
CareFusion will make available, on request, circuit diagrams which will assist appropriately qualified technical personnel
to repair those parts of the device which are designated by the manufacturer as repairable.
Control PCB
Contains the main processor module which provides the control functions for almost all aspects of the pump. It drives
and monitors all other modules using the program code stored in the flash EPROM. The main processor runs the main
application program.
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Power Supply Supervisor
The power supply voltage is monitored by IC6 which provides an active low reset signal to the microcontroller at
power up and if the regulated 5V input falls below a preset level. IC6 also switches battery backup power to the static
RAM IC4 and real time clock chip IC13.
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Real Time Clock
The real time clock chip IC13 maintains time and date information.
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Watchdog
The watchdog alarm will enable the audible alarm on the Power Supply PCB and disable the motor supply current.

Audible Alarm
The key beep/quiet alarm, SP1, is fitted to the Control PCB.
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AC/DC Input
The AC/DC input level is a high or low signal from the Power Supply PCB. The signal from the Power Supply PCB is
high at PL6 when AC is connected and low when the unit is being operated from its internal battery.

Motor Drive and Speed Control
The motor speed is controlled by adjusting both the mark-space ratio of the drive signal and its repetition rate applied
to the DC motor. In normal operation if the watchdog fails power is prevented from reaching the motor.
The motor speed control algorithm uses three feedback signals from optical switches. The optical encoder signals are
all fed via schmitt trigger inverters in IC14. The direction of the motor is monitored during operation using the optical
encoder signals and linear position sensor.

Linear Position Sensor
The linear speed, position and direction of the transmission are monitored using a potentiometer that runs under
the carriage block. As the carriage moves over the potentiometer voltage is produced which is proportional to the
position of the syringe plunger. The software checks for linear movement and the direction every 0.5mm, and checks
the rate every 5mm.

Bonded Beam
The drive force of the pump is detected by measuring the deflection of a beam at the end of the lead screw on the
transmission by using a full bridge strain gauge. The output from the strain gauge is fed to a two stage differential
amplifier, IC1. The offset value of the amplifier i.e. with no pumping pressure applied, can be adjusted using
potentiometer RV1, and is set during calibration.
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Pressure Transducer (Model P7000 only)
In-line pressure measurement is detected by a pressure transducer. When a force is applied to the pressure transducer
an output voltage proportional to the force is generated.

Disc Detect (Model P7000 only)
The pressure dis c is detected by a slotted optical switch. When the disc is not fitted the opto switch is off, when the
disc is fitted the opto switch is on. The signal is fed to IC9.

Plunger Detect
The syringe plunger button position is detected using a slotted optical switch. The signal from the optical switch
changes state when the syringe plunger is located correctly; this signal is fed to IC9.

Transmission Disengaged Detection
A micro switch is mounted on the transmission carriage to detect when the transmission drive has been disengaged.
The signal from the micro switch changes state when the declutch lever is activated. This signal is fed via IC14 to the
microcontroller.
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Keypad
The membrane keypad is fitted to the upper case and connections are made via a flexible circuit that plugs into PL2.