Labconco Protector Controlled Atmosphere Glove Boxes 5080102 - Manual (Page 26)

NORMAL OPERATION
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Transfer Chamber Valves and Gauge (Models 5060000, 5060100, 5070000 and 5070100 with
Manual Pressure Control)
With inner and outer transfer chamber doors closed and latched and transfer chamber “fill”
and “vacuum” valves closed (valves handles horizontal), switch exterior outlet “ON” to start the
vacuum pump. Open the vacuum valve and observe the vacuum gauge as the transfer chamber
decompresses. When it reaches the vacuum level you plan to use for a purge level, close the
vacuum valve, turn off the pump, open the “gas fill” valve and observe as the gauge returns to
atmospheric pressure. Close the “gas fill” valve.
CAUTION: If connections have been made for backfilling the transfer chamber from the
glove box, you must also observe the glove box pressure and throttle the glove box “gas in”
valve and the transfer chamber vacuum valve to make sure the glove box pressure does not
measure below -5" water column.
NOTE: Precautions should be taken to make sure the inner transfer chamber door is
closed and sealed while purging the transfer chamber with vacuum. Failure to do so will
result in the pressure relief bubbler relieving pressure, thereby, introducing laboratory air to
the glove box.
Glove Box Valves, Gauge and Controls (Models 5070000, 5070100, 5080000 and 5080100
with Pressure Control Module)
With the inner door closed and the glove box “gas in” and “gas out” valves closed (valve
handles horizontal), open the gas supply tank valve. Adjust the high/low limit switches to indicate,
by the dim light band in the display, positive pressure between +2 and +3. Next open the “gas in”
valve. The glove box pressure, indicated by the bright light display segment, will be increased to
within +2 to +3. Adjust the high/low limit switches to a span of –2 to –3, and then open the “gas
out” valve. The glove box pressure will then be decreased to within the –2 to –3 span on the
negative display as indicated. Leave the manual valves on.
Actuate the pressure setting switches to increase or decrease the pressure momentarily
beyond the limits of the span. When you release these switches, the pressure will automatically
return to within the indicated span. Repeat this check out procedure by using the foot-operated
switch. NOTE: Take care not to exceed the range of ±5" H
2
O.
Adjust the high/low limit switches to a span of –1 to +1 and actuate the pressure setting
switches to give actual pressure of zero.
NOTE: On Models 5070000, 5070100, 5080000, and 5080100, the manual control valves
must remain open to provide automatic control of glove box pressure. If a malfunction occurs in
the pressure control system, the manual valves can be closed to protect the established glove box
environment.