Mindray WATO EX-55Pro, Service Manual

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6.6.6 Check the Pressure Sensor Accuracy
NOTE

Generally, measurement deviations do not easily occur to pressure sensors.
However, in case of maintaining or replacing the monitor board, three-way valve
assembly, or expiratory valve assembly, you need to perform pressure calibration
and check the flow sensors accuracy so as to confirm the effectiveness of
calibration.
Checking the pressure sensor accuracy is to check:
 The measurement consistency between the pressure sensors inside the machine;
 The measurement accuracy of any single pressure sensor inside the machine;
 The validity of (factory) pressure calibration result.
To check the measurement accuracy of pressure sensors:
1. Make sure that the pressure sampling line and calibration device (or other pressure
measurement device) are connected in parallel, similar to tubes connection in pressure
calibration. For details, refer to
7.3.3 Pressure Calibration (Service).
2. When the system is Standby, select the [Maintenance] shortcut key → [
Factory
Maintenance
>>] → [
Diagnostic Test
>>] → [
Valves—Test Tool
>>] to access the
[
Valves—Test Tool
] menu.
3. Set PEEP safety valve to [
ON
].
4. Increase the D/A value of the PEEP valve, causing the measured pressure value of the
anesthesia machine calibration device to fall with the following ranges respectively:
(5±1) cmH2O, (20±1) cmH2O, (50±1) cmH2O, (70±2) cmH2O, (90±2) cmH2O. Record
the measured pressure values of the airway pressure sensor and PEEP pressure sensor to
which each setting corresponds respectively.
5. Make sure that the deviation between the measured data of the airway pressure sensor,
PEEP pressure sensor and that of the anesthesia machine calibration device must not
exceed 1 cmH2O or 2% of the measured value of the calibration device, whichever is
greater. Otherwise, refer to
7.3.3 Pressure Calibration (Service)
to perform pressure
calibration again.