Binder CB 170 - Gas Supply Requirements and Control Activation;Deactivation

CB (E7) 06/2018 Page 54/174
6.7 Required gas supply for the chamber with O
2
control
In the chamber with O
2
control, cell growth can be additionally influenced by a variable oxygen content.
Depending on the required range of O
2
concentration, the type of gas which is required may vary. To this
end, two equipment variants are available:
6.7.1 Hypoxic control range 0.2 vol.-% up to 20 vol.- % O
2
(regular)
In addition to the CO
2
connection, the chamber provides a gas connection for N
2
.
As compared to the ambient air (O
2
concentration of 20.9 vol.-%) only the N
2
concentration needs to be
increased, no oxygen is required for the O
2
control. Therefore, it is not necessary and possible to connect
an O
2
cylinder. Even with activated O
2
control no O
2
pressure alarm will be emitted.
6.7.2 Alternative control range 10 vol.-% up to 95 vol.-% (option)
In addition to the CO
2
connection, the chamber provides gas connections for O
2
and N
2
.
• Operation in the hyperoxic range (> 22 vol.-% O
2
)
As compared to the ambient air (O
2
concentration of 20.9 vol.-%) only the O
2
concentration needs to
be increased, no nitrogen is required for the O
2
control. Therefore, it is not necessary to connect a N
2
cylinder.
You can deactivate the N
2
pressure alarm in the controller (chap. 7.3). Then also with activated O
2
control no N
2
pressure alarm will be emitted.
• Alternating operation in the hyperoxic and hypoxic range or in the range from 20 vol.-% O
2
up
to 22 vol.-% O
2
N
2
and O
2
are required for O
2
control. It is necessary to connect all gas supplies.
You can deactivate the O
2
and / or N
2
pressure alarm in the controller (chap. 7.3). Then also with
activated O
2
control no O
2
and / or N
2
pressure alarm will be emitted.
6.7.3 Operation without O
2
control
You can deactivate the O
2
control in the controller (chap. 6.8). With this setting, no O
2
and N
2
pressure
alarms and no O
2
tolerance range alarm will be issued. The zero-voltage relay alarm contact (chap. 11.6)
will also not be triggered.
Since neither nitrogen nor oxygen are required, it is not necessary to connect an O
2
or N
2
cylinder.