Arjohuntleigh FLOWTRON UNIVERSAL, Service Manual

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Flowtron Universal Service Manual Introduction
Issue 2 Chap 1
Sep 2009 SER0009 Page 3
3 Technical Description
The pump consists of an electronically controlled air compressor with associated air routing and alarm
facilities. The operation of all the pump features is driven by microcontroller software.
The key parts of the pump are as follows:
• Compressor. This provides a flow of air to the pneumatic system, thus allowing inflation of the
garments. The output of the compressor is fed to the motor and manifold assembly.
• Motor and Manifold Assembly. This includes a rotary valve which routes the air pressure to the
garments. The rotary valve also makes sure that as one garment is being inflated, the other
garment is vented to the atmosphere.
• Pressure Transducer. This provides the monitoring system with the means of accurately measuring
the pressure fed to each garment.
• Control Printed Circuit Board (PCB). This PCB controls the compressor, the motor and manifold
assembly, and the illuminated graphic LCD display panel. It also performs a continuous check of
the operation and performance of the pneumatic circuit. In the event of a detected fault, the
electronic monitoring system generates both visual and audible alarms.
• Power Supply Printed Circuit Board (PCB). In addition to generating the DC voltages for use in the
pump, the PCB provides interfaces to the compressor and the optional battery pack.
• Automatic Garment Recognition Facilities. The connector on the end of each pump hose set
contains a sense coil which is connected to the control PCB, and is used to automatically recognise
the type of garment fitted to the connector (foot garment, or single chamber calf garment).
Pressure Transducer Calibration
The pump utilizes a precise and accurate pressure measurement and control system, which is not
expected to require re-calibration until after several years of continuous use. The measurement system
automatically handles any adverse effects due to drift or temperature change and should not require any
user intervention.
The pump is factory-calibrated, and should not normally require field re-calibration.
However, the pressure shown on the LCD display should be verified for accuracy during each routine
maintenance.
Alarms
The pump has both audible and visual alarms. If a problem occurs, the system will detect the fault and
flash a message on the LCD display. If the same fault continues for 10 successive inflation cycles (which
will be between 5 and 12 minutes depending on the garment types connected to the pump), the audible
alarm sounds, the red alarm LEDs flash and a description of the fault condition is indicated on the LCD
display. If the fault condition is unaltered, the audible alarm will increase in pitch until the fault is corrected
and/or the system is reset.
Note: If a Pump Fault is detected, the pump will alarm immediately.
Battery on the Control PCB Assembly (if fitted)
The battery on the control PCB assembly provides power for the real time clock. The battery should not
require replacement until after several years of continuous use. If the battery has to be replaced, then it
must be replaced in less than 20 seconds, or else the real time clock will lose its time and date settings.
If the time and date settings are lost, they have to be reloaded from a PC-based service tool, so the
procedure should only be carried out in a ArjoHuntleigh service environment.
Schematics
Refer to Figure 8 for the Pneumatic/Control Schematic of the pump.
Refer to Figure 9 for the Electrical Schematic of the pump.