5.3.4
Prepare the sensors
Important
Do not start pH or DO reading until the medium is fully equilibrated to operating condi-
tions. The sensors do not give reliable measurements until then.
Equilibrate the culture medium with 100% air to calibrate DO sensors for 100% air satu-
ration. If you use air mixed with 0% to 10% CO
2
, the sensors can be calibrated over the
range 100% to 90% air saturation.
Do not calibrate DO sensors for 100% air saturation if N
2
is used instead of air.
CO
2
regulation is slow, so it takes some time before the CO
2
concentration
reaches the setpoint.
Note:
NOTICE
Do not move the rocker during a run, since this could damage the
scale function and disturb the weight measurement.
Prepare the DO sensor
Follow the instructions below to prepare the DO sensor.
In dual mode, adjust the sensor calibration on each Cellbag bioreactor sepa-
rately.
Note:
Action
Step
When the medium is equilibrated to operating conditions, move the cursor
over the DO sensor icon in the Process Picture, and set Reading On in the
menu that appears.
1
Wait until the value is stable.
Select System:Calibrate in System Control.
2
Select DO sensor in the Monitor to calibrate drop down menu.
3
Enter percentage of air saturation (90% to 100% depending on CO
2
concen-
tration) in the Enter reference DO field.
4
Click Calibrate.
5
Close the Calibration dialog.
6
Select Settings:DO in the Process Picture.
7
ReadyToProcess WAVE 25 Operating Instructions 29009597 AD
141
5 Operation
5.3 Prepare for cultivation
5.3.4 Prepare the sensors
