7
New Brunswick Scientific
User’s Guide
3.7 DO
Control
Dissolved oxygen (DO) is controlled in the range of 0-200%. It is sensed by the DO
electrode and control is maintained by the P & I controller by changing the speed of
agitation, the thermal mass flow controller-regulated flow rate (if your system is so
equipped), and/or the percentage of oxygen in aeration.
Default P & I (proportional & integral) values are preset at the factory.
We strongly
recommend that you maintain the factory-set parameters.
The DO probe is a polarographic probe. Be sure to inspect the DO probe before every
run, changing the electrolyte solution and membrane as needed.
3.8 Foam/Level
Control
Foam can be monitored during batch fermentation by a foam/level probe located in the
headplate. The controller operates the antifoam-assigned pump that adds chemical
defoamer into the vessel as needed. The internal level can also be controlled by using
this feature. Pumps can be triggered to turn on or off in response to the presence or
absence of liquid.
3.9 Exhaust
System
The exhaust gases pass into the exhaust condenser
(see Figures 13 and 14)
where
moisture is removed, then returned to the vessel. The remaining gases then pass
through a 0.2
μ
m exhaust filter. Be sure to inspect filters before every run, replacing
them as needed.
WARNING!
NEVER block the exhaust to pressurize the vessel!
3.10
Recommended Accessories & Supplies
Before you begin to assemble your BioFlo/CelliGen 115, it would be prudent to verify
that you have all of the following accessories and supplies readily at hand:
