15. With the Gas System switch ON and the Vacuum, Nitrogen, and
Equalize switches in the Auto position, repeat Steps 6 through 8 five
more times.
16. Turn OFF the Manual Fill knob when the procedure is complete.
17. Turn the Catalyst Fan switch ON.
18. After one hour, open a BBL strip and check to see if the chamber is
anaerobic. The cabinet should now be below 1% oxygen.
Caution
Let the cabinet sit overnight before adding the cultures. This
permits the catalyst wafer to remove any traces of oxygen that may be
present.
s
The interchange is used to transfer items to and from the work chamber
without contaminating the work chamber with atmospheric gas. The
vacuum pump is programmed to operate until it pulls a 20 in/Hg vacuum.
Nitrogen is injected until the interchange reaches atmospheric pressure and
the interchange equalizes with anaerobic gas mixture until it reaches work
chamber pressure.
The transfer cycle is factory-set for three evacuations, two nitrogen purges
and one equalizing purge of anaerobic gas mixture. The operator may alter
the transfer cycle to one nitrogen purge, two vacuum functions, and one
equalizing purge of anaerobic gas mixture. Refer to Section 4.9 for
instructions in making this adjustment.
The duration of the transfer functions may be manually controlled by
setting any one of the three function switches to the Manual position.
Note
Only one function switch may be in the Manual position at any
given time. Having two or more switches in the Manual position at the
same time wastes gas.
s
Caution
When using any of the function switches on Manual, the operator
must remain in the room and pay strict attention to system operation.
s
Both the inner and the outer door must be securely closed during the
transfer cycle. The doors should not be reopened until the cycle is
completed and the appropriate door indicating light goes out.
Anaerobic System 1-9
Thermo Scientific
Section 1
Installation and Start-Up
Start-Up Procedure
(continued)
Automatic Operation
of the Interchange
