NEW BRUNSWICK SCIENTIFIC BioFlo 4500, Руководство по эксплуатации

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BioFlo 4500 M1254-0050 User’s Guide
104
12. A message will appear. Press
YES
to accept changes to the DO control
loop,
NO
to decline.
13. Exit the
MAIN CONFIGURATION SCREEN
by pressing the
CLOSE
BUTTON
. The control mode of the DO control loop display gauge in
the
GAUGE SCREEN
will now display
3-Gas
.
13.5 Four-Gas
13.5.1 Control Action
Air, oxygen, nitrogen, and carbon dioxide are mixed in response to pH
and DO culture demand as indicated by pH and DO loop outputs. The
controller determines the gas ratios, and ensures a constant and continuous
gas flow at all ratios.
13.5.2 Control Procedure
To configure a four-gas mix:
1. Set up a cascade in which the output of the pH control loop is input to
the DO loop. The specific setpoint and output values in the cascade do
not matter. The Gas Mix algorithm alone determines the gas mix
ratios.
2. From the
GAUGE SCREEN
, press the
CONFIG. BUTTON
. The
MAIN
CONFIGURATION SCREEN
will appear.
3. Select the DO control loop and press
CONFIGURE
. The
LOOP
CONFIGURATION SCREEN
will appear.
4. Touch the
CONTROLLER ICON
in the
LOOP CONFIGURATION
SCREEN
. The
CONTROLLER SETTINGS SCREEN
will appear.
5. For the
OUTPUT TYPE
, select
GAS MIX ,
and for the
OUTPUT ACTION
,
select
CENTER OFF
.
6. Enter the
PWM PERIOD
in seconds (the default value is 10 seconds) by
pressing on the text box and entering in the time using the keyboard.
The
PWM PERIOD
is the time that controller will cycle through each of
the connected SSRs.
7. Press
OK
to accept these settings, and to return to the
LOOP
CONFIGURATION SCREEN
.