Specifications
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5001FAOPT71 ISS 8.0
Service Equipment
Technical Description
The following details outline the safety checks designed into IVAC Syringe Pumps to minimise the possibility of
under/over infusions.
MONITORING OF THE SYSTEM CLOCK FREQUENCY / WATCHDOG
The system clock, which is used to control the rate of the pump is derived from the microprocessor crystal
oscillator. A watchdog circuit is implemented in the pump to monitor the correct time period. The watchdog circuit
requires the microprocessor to send a reset pulse every 10mS to stop the counter from timing out and triggering
the watchdog alarm. The reset signal has to be in a time 'window' of between 8 to 12mS. If it is either too fast
or too slow the watchdog hardware will detect this and generate an alarm and disable the motor drive.
Additionally, on power up the watchdog is allowed to time-out and the period is measured and tested to be within
a set tolerance. This then confirms that both the microprocessor crystal and the watchdog crystal frequencies
are correct.
DETECTION OF LINEAR MOVEMENT
A linear potentiometer is incorporated in the unit to detect the movement of the pumping mechanism. This
movement is monitored in the electronics and software of the system. If it is detected that the mechanism is
either moving too fast, too slow, or not moving at all then an error code will be displayed, the motor drive will be
disabled and the pump will stop.
CONTROL OF LINEAR SPEED / INFUSION RATE
The pump mechanism is driven using a d.c. motor; feedback for the control system is provided by two opto
switches. To enable the motor drive there are three transistors which need to be turned on. The correct
operation of these transistors is tested on power up. The control system monitors the feedback from the opto
encoders and adjusts the motor on time to maintain the required speed. If there are no encoder signals
feedback, indicating that an opto has failed or the transmission has jammed, an error code will be displayed and
the pump will fail-safe. If there are too many encoders detected by the encoder feedback indication that a
transistor has gone short circuit an error code will be displayed and the pump will fail-safe. The pump calculates
the appropriate motor control rate from the set infusion rate and syringe constant data stored within the pump
software. The syringe constant data converts ml’s to mm’s of movement for each syringe type and size.
These IVAC “P” Series Syringe pumps have been designed to allow simple and low cost servicing. Standard
components are employed where possible so that no special test, calibration or tools are required. However,
the following items may be useful for general servicing.
Part Number
Description
0000TG00020
Occlusion Test Gear
0000TG00002
Linear Accuracy Test Gear
0000TG00032
PCAM
Cover Detect Actuator Magnet
0000TG00055
Syringe Sizing Spacer
5000JG00001
Cradle P5000
0000JG00014
Plunger Detect Protector
1000EL00043
Ribbon Cable Extension
Summary of Contents for P5000 Mk II
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