Mindray A8 - Constant Flow Test (Checking the Flow Sensor Accuracy)

5-24
The following table lists the normal range of the zero point of some pressure and flow sensors.
Sensor Normal Range of
Zero Point (AD
Counts)
PAW sensor
1068-1765
PEEP sensor
1068-1765
Esophageal pressure sensor (Canada Only)
1068-1765
Inspiratory flow sensor
289-632
Expiratory flow sensor
289-632
Balance gas flow sensor (EFCS)
0-200
O2 flow sensor (EFCS)
0-200
Total flow sensor (EFCS)
0-200
If the current zero point exceeds the specified normal range and the actual value is greater than 1,
calibrate the zero point again. If the actual value is less than 1 and the zero point of the PAW
sensor, PEEP sensor, or inspiratory/expiratory flow sensor is beyond the range, replace the VCM.
If the zero point of the balance gas flow sensor, O2 flow sensor, or total flow sensor is beyond the
range, replace the flow sensor or its interface board.
NOTE
 If the zero point of the pressure sensor is inaccurate in case of ventilation, the
baseline of the PAW waveform is not at the zero point and a great deviation exists
between pressure control and measurement.
 If the zero point of the inspiratory/expiratory sensor is inaccurate in case of
ventilation, the baseline of the PAW waveform is not at the zero point and a great
deviation exists between TV control and measurement.
 If the zero point A/D value of any sensor runs out of the normal range, it cannot be
corrected. Instead, the monitoring signal test board must be replaced.
5.16 Constant Flow Test (Checking the Flow Sensor Accuracy)
To check the measurement accuracy of flow sensors, perform the following operations:
1. Remove the water collection cup.
2. Use a tube to connect the inspiratory port and expiratory port of the anesthesia machine, as
shown in the following figure.