ASP STERRAD 100, Service Manual

Page: 143 / 309

Door and Chamber Theory of Operation
Chamber Subsystem
The chamber is connected to the vacuum subsystem through an
aperture at the bottom rear of the chamber. Through this aperture the
chamber is pumped down during the vacuum stage, and filtered ambient
air is admitted to it during the vent stage.
The patented injector valve assembly, containing the needle and
vaporizer assemblies, is mounted through the top front boss of the
chamber.
At the bottom middle of the electrode screen is the feedthrough copper
shaft connecting the electrode screen inside the chamber to the RF
match module.
Door Subsystem
The door moves vertically at a speed of 200 mm/sec ±5 mm/sec. and is
actuated by means of a pneumatic cylinder. If a vacuum is present, the
vacuum helps hold the door closed. If the power fails during a cycle, and
is not reapplied, the door can remain closed for up to several days until
the normal, minimal leakage returns the chamber to atmospheric
pressure. If power is reapplied and the chamber vented, the door can be
opened. If no vacuum is present, the door opens automatically at power
failure.
If the power failure has a duration of less than 1 minute, and occurs in
the vacuum stage, the period between 10 and 48 minutes of the
diffusion phase, or the vent stage, the cycle continues normally.
Otherwise, whenever the power is restored, the software computes where
in the cycle it was when the power failed, and enters the correct abort
cycle. During the process, the door remains closed.
Operation
F
Door operation is controlled by the touch sensitive push buttons:
START, OPEN DOOR, CLOSE DOOR
, and
CANCEL
.
F
The operator closes the door (opens the door) using
CLOSE DOOR
(OPEN DOOR
).
F
Pressing
START
begins the process by closing the door if it is open,
and continues through a complete sterilizing cycle.
Door and Chamber Theory of Operation Door and Chamber Subsystem
ASP Service Guide rev D STERRAD® 100 Sterilizer 7-3