6-12 
 
6.3.2 O2 Sensor Calibration (User) 
6.3.2.1 Principles 
  The O2 sensor needs to be calibrated when a great deviation occurs in the O2 
monitored value or the O2 sensor or VCM is replaced. 
  Observe whether the O2 sensor displays values on the measure screen before 
calibration. If not, check whether the O2 measure switch is turned off, check the 
connection cables of the O2 sensor, or replace the O2 sensor until values are 
displayed on the screen. 
  The O2 sensor needs to be calibrated at 21% O2 and 10
corresponding standard gases with the O2 concentration are required. 
  O2 calibration is not available if an AG is plugged into the system. 
 
6.3.2.2 Calibration Procedure 
Calibration at 21% O2 
Perform the following steps to calibrate the O2 sensor at 21% O2. 
1.Select 
 > O2 to access the following menu. Follow the instructions on the screen to set 
the machine. Select Begin to start calibration. The normal voltage range of the O2 sensor is 
245–275 mV at 21% O2.