(9) Phase 17: heat/exposure. 1SOL and 5SOL are energized (opened).
Steam pressurizes the chamber. When the 131C exposure temperature is reached (as
sensed by the temperature transducer in the chamber drain line), the exposure time
begins. 1SOL de-energizes (closes) and energizes (opens) as necessary to maintain
selected exposure temperature. When the three minute exposure time expires, 1SOL
and 5SOL are de-energized (closed).
(10) Phase 24: vent/dry. 2SOL and 6SOL are energized (opened). The
chamber pressure is reduced to 4.8psia. 2SOL and 6SOL remain energized (opened)
for a 10 minute drying time. Then 2SOL and 6SOL are de-energized (closed).
(a) Vent will last until the dry timer displays time and begins to count
down. This phase is also known as exhaust.
(b)
At the end of the dry time, there is a 20-second delay before the
next phase.
(11) Phase 40: leak test. A one minute dwell period allows the chamber to
stabilize at the negative pressure. This is followed by a 15 minute leak test. Pressure is
recorded at the beginning and end of the 15 minute leak test. If the established leak
rate is exceeded, the leak test fails, and warning code 79 is signaled on the
control/display panel.
(12) Phase 31: air-in. 3SOL is energized (opened). Filtered atmospheric air
enters the chamber and raises the chamber pressure to the atmospheric reading.
When the chamber pressure reaches the atmospheric reading, 3SOL is de-energized
(closed).
(13) Phase 35: gasket retract (single door units. 10SOL is de-energized
(closed to steam/opened to the ejector). 6SOL is energized (opened). Water to the
ejector creates a negative pressure in the gasket groove, retracting the door gasket
within 30 seconds. The complete buzzer then sounds and shuts off after the door is
opened or one minute has elapsed.
(14) Phase 35: gasket retract (double door units). The complete buzzer
sounds and shuts off after either the unseal door switch has been pressed or one
minute has elapsed. Pressing the desired unseal door switch de-energizes (closes to
steam/opens to the ejector) the gasket solenoid valves (10SOL and 11SOL). 6SOL is
energized (opened). Water to the ejector creates a negative pressure in the gasket
grooves, retracting the door gaskets within 30 seconds, and doors can be opened.
MD0354
1-27