4-41 
 
4.14.3 Constant Pressure Test (Checking the Pressure Sensor 
Accuracy) 
 
NOTE 
  Generally, measurement deviations seldom occur to pressure sensors. However, in 
case that the ventilator control board, solenoid valve assembly, or expiratory valve 
assembly needs to be replaced, you must perform pressure calibration and check 
the pressure sensor accuracy so as to confirm the effectiveness of calibration. 
  You can use any flowmeter with an accuracy of at least  ±2% for the accuracy 
measurement of the pressure sensors. 
 
To check the measurement accuracy of pressure sensors, perform the following operations: 
1.  Complete pneumatic connections as follows: 
The following picture shows a four-way device. 
 
 
a.  Remove the top cover (3 captive screws). 
b.  Remove the two tubes marked as #72 and #9 from the pressure sensors (refer to a figure 
below). 
c.  Connect the four-way tube to the pressure sensor P1 of the monitor board, PEEP 
pressure sensor P2, the tube marked as #72, and the low pressure port of Fluke VT-Plus. 
The tube marked as #9 will remain unconnected for this calibration.