KrosFlo® Systems
User Guide
15 repligen.com IF.UG.028 R1
Table 4. Input parameters for Main screen
7.4
Automatic (Process) Mode
KrosFlo® Systems are designed with an automated Process Sequence that controls a product
concentration step followed by a diafiltration (wash) step and then a final concentration step. The
process mode includes an option for use of Fed Batch mode.
The
CONCENTRATION
steps allow the system to run at a constant Transmembrane Pressure (TMP)
and recirculation flow (P-01 LPM) while concentrating the initial product sample volume to a
predetermined volume reduction. The volume reduction, or Concentration Factor (CF) is determined
by the user.
DIAFILTRATION
sets the system to run at a constant Transmembrane Pressure (TMP) and
recirculation flow rate (P-01 LPM) while washing the concentrated sample product volume
(diafiltering) with buffer. The amount of wash (Diafiltration Volume, or DV) is determined by the
user.
DV Setpoint
is used as the end point of the diafiltration sequence. This number signifies the
number of diafiltration volumes that will be processed.
FED BATCH CONCENTRATION
allows the initial concentration step to include additional volume from
a vessel external to the primary recirculation vessel being used. The calculations for process
estimate the remaining volume based on the permeate flow and scale reading for the main vessel.
When the main vessel weight reduces below the
Level Setpoint During Concentration
setpoint for
the time defined by the
Sample Feed Pump Stop Delay
setpoint, the KrosFlo® System will assume
the feed vessel is empty and switch its volume calculation to monitoring only the scale.
The
FINAL CONCENTRATION
step takes place once the diavolume setpoint has been reached for the
diafiltration step. The concentration factor is set on the process Settings screen and can be observed
from the Main screen.
The process steps are accessed on the Settings screen (see
). A
Reset Windup
button is
available on the Settings Screen to reset PID control parameters after the system has been stopped.
This feature allows for a smoother restart of the system at auto process parameters. When the
Reset Windup
button is not pressed, the control loop will start at the pump speeds previously
arrived at output.
Parameter
Range
Units
VALVE BPCV-01:
Manual Mode
Auto Mode
0 - 100
0 - 30
%
psi
Pumps:
P-01 Manual Mode
P-01 Auto Mode
P-02 Manual Mode
P-02 Auto Mode
P-03 Manual Mode
P-03 Auto Mode
0 - 9000
0 - 10/45/85
0 - 650
0 - 20
0 - 650
0 - 20
rpm
lpm
rpm
lpm
rpm
lpm
P-01, P-02 and P-03 may change depending on the system design, pump models and identification tags
used.
