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BioFlo/CelliGen 115
y
M1369-0050
User’s Guide
7.3
Dissolved Oxygen (DO) Probe Preparation
7.3.1
Inspecting the DO Probe
Inspect the probe for possible shipping damage. Immediately report any
damage you may observe to the New Brunswick Scientific Service
Department.
Remove the protective cap from the electrode end. The membrane is delicate
and care must be exercised to prevent accidental damage.
NEVER REST
THE PROBE ON ITS MEMBRANE.
7.3.2
DO Probe Preparation
To ensure stable output, the probe should be sent through two or three
sterilization (autoclaving) cycles prior to use. The probe will be operable after
the second cycle, but it will be more stable with additional sterilizations.
The
shorting plug should be installed on the probe during autoclaving or
sterilization.
Default P & I (proportional & integral) gains are preset at the factory. They
are different for each operating mode, fermentation and cell culture.
It is
strongly recommended that you maintain the factory-set parameters.
Nevertheless, P & I gains for the DO loop can be modified by the operator,
using the touchpad on the front of the control cabinet.
As noted above, fermentation mode and cell culture mode require different P &
I values to ensure proper DO control. Whether you choose to use (as
recommended) the factory-set values or to alter them, it is highly unlikely that
you will ever need to re-set or change them. Even if the power fails during a
run, the P & I values (pre-set if you do not change them, or your settings when
you do) are stored in memory and should still be in effect when the power is
restored.
For details regarding P & I settings, see Section 19, Appendix B.
Nevertheless, it is always prudent to check these values at the beginning of a
run, especially if the fermentor has not been used for a while or if other people
have access to the unit.
#
NOTE:
It is recommended that you use the factory-set P & I values. Do not
attempt to change the settings unless you are experienced with P & I
control.
