Labconco Protector Controlled Atmosphere Glove Boxes 5080102 - Manual (Page 28)

NORMAL OPERATION
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“sequence” indicators (the number of cycles selected) will remain lighted until the next
purge/fill cycle is started.
C. Clear Switch. Actuating this switch prevents the purge/fill cycle form progressing through
the entire sequence. The system will advance directly to the last fill cycle and then end the
sequence.
D. Manual Mode. Actuating either the “Purge” or “Fill” switch overrides all automatic
controls:
Purge Switch – Depress this switch to operate the vacuum pump and evacuate the transfer
chamber. The vacuum pump will continue operating until this switch is again depressed,
then released.
Fill Switch – Hold in this switch to fill the transfer chamber. Release the switch
intermittently (if back filling from the glove box) as necessary to ensure the glove box
pressure level does not measure below -5" H
2
O. Release the switch when pressure in the
transfer chamber reaches zero. Do not pressurize the transfer chamber.
General Operating Instructions
Important note: All operators of this equipment should thoroughly read and understand
the preceding information under Operation of Controls before beginning this operating
instruction section. After becoming familiar with the glove box controls, you are ready to fill the
glove box with inert gas and begin your operations.
Only the user can determine what type of atmosphere and pressure level is appropriate for
the type of work being performed. If the ill effects of air in leakage outweighed the effects of out
leakage, one would choose to operate under a positive pressure. Set the “High and Low Limits”
on the Control Panel entirely in the positive pressure range. As long as viable samples are kept in
the unit, the controls, inert gas supply, and vacuum pump should remain active. The pump and gas
are necessary to compensate for temperature/pressure swings that would cause a box to go from a
positive pressure state to a negative pressure, or vice versa.
Establishing Inert Gas Environments:
The inert gas environment may be achieved by alternately purging and filling the glove box
or by simultaneously throttling the “gas in” and “gas out” valves while gas flows through the glove
box on Models 5060000 and 5060100. On Models 5070000, 5070100, 5080000, and 5080100,
this may be done by actuating the pressure setting, “Increase” and “Decrease” switches. During
either method, observe the glove box pressure gauge to see that it remains between ±5" water
column.
Determine the appropriate pressure for your operating procedures and adjust accordingly.
Usually a comfortable glove manipulation level is between ± 0.3" to 0.8" water column.