NEW BRUNSWICK SCIENTIFIC BioFlo 4500, Руководство по эксплуатации

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New Brunswick Scientific Co., Inc. User’s Guide
123
1
1
6
6
M
M
L
L
-
-
6
6
1
1
0
0
0
0
P
P
H
H
C
C
O
O
N
N
T
T
R
R
O
O
L
L
NOTE:
The following paragraphs only refer to the use of the BioFlo 4500
equipped with the ML-6100 controller .
During the growth cycle, control of the pH may be required. The BioFlo 4500 is pre-
configured at the factory to include a pH control loop. The pH control system is optional.
A pH probe is provided for side mounting in a 25 mm Ingold type penetration in the
lower side-wall of the fermentor vessel subsequent to filling the vessel. The electrode
assembly is steam-sterilizable-in-place at the same time the media and vessel are
sterilized. The pH probe is connected via a probe cable to the pH connector on the front
panel of the console. The pH probe generates a mV signal that is amplified and
conditioned near the probe to become the input to the controller that monitors the pH.
When the pH exceeds the desired value (as preset) an addition of acid is introduced
automatically into the vessel; when pH is too low an addition of base is introduced
automatically into the vessel. In the PWM mode of control a timed addition can be used
to permit sufficient time for the acid or base to be properly mixed with the fermentation
broth prior to a subsequent addition.
The pH value is also continuously displayed on the touchscreen. Two peristaltic addition
pumps are required; one for acid addition and one for base addition. The BioFlo 4500
should be set for pump 1 and pump 2 to perform the task of acid and bas addition. Sterile
acid and base reagent and their containers are also required. Optional 19 mm re-
sterilizable addition ports with quick fit connections with appropriate valving and traps
installed in the upper sidewall of the vessel may be used for introduction of the acid and
base to the fermentor vessel. Alternatively, optional hose barb ports or septum ports
located in the headplate or upper sidewall may be used for introduction of acid and base.
Operation, maintenance and troubleshooting of pH probe are described in corresponding
manuals which accompany this manual.