2-36 
 
EFCS flowmeter monitoring board (bottom view) 
2.2.5.2 Flow Sensor Board 
The flow sensor board is mainly used to monitor the O2/N2O/air flow and feed back the detected 
signals to the EFCS flowmeter monitoring board through the I2C bus. 
 
Installation position of the flow sensor board 
 
Flow sensor board (top view)           Flow sensor board (side view) 
 
2.2.5.3 BFCS Switch Board 
The BFCS switch board is mainly used to monitor the open/closed status of the BFCS door. Two 
Hall switches are used to feed back the status signals of the BFCS door to the EFCS flowmeter 
monitoring board.