Smiths Graseby 3200, Техническое и сервисное руководство

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Smiths Medical International Ltd.
3200 Service Manual Issue 5 (August 2004)
3 — 4
Sensing (alarm) systems
The sensing circuits incorporate a system that monitors the output of the batteries and
registers an alarm if the voltage of the batteries drops below 5.75 V.
If the voltage falls below 5.4 V the pump turns itself off after an initial warning period.
At switch on the pump completes various self tests. In addition, the rotation of the slotted
disc at the end of the leadscrew is monitored to ensure that the drive mechanism is operating
correctly.
The software continually checks itself for the validity of the calculations.
Battery voltage
low
Self tests/pump
malfunction
Drive
disengaged or
syringe not
fitted
The pump’s drive system is designed so that it is only engaged when the top of the syringe
is correctly positioned in the plunger clamp.
If the plunger clamp is displaced during an infusion, the drive automatically stops due to the
disengagement of the half nut. The disengagement of the half nut is detected by an opto-
sensor.
If the pump tries to operate without a syringe, or with a syringe incorrectly fitted, the pump
goes into an alarm state.
The syringe sizing system comprises a flag moulding assembly ( Figure 7.2 ) that rests on the
barrel of the syringe. In conjunction with three size sensors ( Figure 7.6 ), it measures the
diameter of the syringe being used.
The flag moulding rotates about the outer of the two guiding tubes and moves an actuating
flag between the three size sensors.
The flag is able to de-activate the three size sensors in any one of the following combinations:
none; 1; 1-2; 1-2-3; 2-3 or 3.
Depending on the operation of the size sensors, the pump monitors the size of a syringe as
being 5 ml, 10 ml, 20 ml, 30 ml or 50/60 ml.
Alternatively, if a syringe is not fitted onto the pump or a syringe smaller than 5 ml is fitted,
then the
SYRINGE INVALID
alarm is activated
.
Syringe sizing
system
For each size of syringe, there is a maximum rate at which the pump is able to infuse. The
syringe size maximum rate can be constrained to an absolute maximum rate by using the
associated parameter within the Configuration mode.
When an infusion is started, the pump checks that the maximum rate constraints have not
been exceeded.
In Intermittent mode, an alarm message is given if any of the following conditions occur:
• the dose volume is too large,
• if the background rate is too high,
• if the cycle time is too short, or
• if the sdose duration is too long or too short.
Rate setting