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-Hard
limiter
When the temperature in the chamber which was detected by the lateral thermistor (TH1) rises to higher
than 140'C, the Triack and the relay control circuit is controlled directly by TH1 temperature detection and
the power supply to the heater is shut down.
This circuit is not controlled via micro-computer and it is reset automatically when the temperature lowers.
(Actuated in all processes.)
- Pressure safety valve
This valve opens to exhaust steam in the chamber and prevent abnormal pressure rise so that the pressure
in the chamber should not exceed O.25MPa.
(5) Functions of specific parts and cautions
<Deaver interlock
This is a safety device to prevent the user from opening the cover by mistake when the pressure in the
chamber is higher than the atmospheric pressure.
In order to check seating tightness between the lid and the chamber, micro-switches are mounted to their
lock shafts.
Also, 1 micro-switch is mounted for detection of the position of the solenoid for the movable handle lock and
2 micro-switches to the lid for detection of lid open/close status.
-When the cover is closed, the 2 micro-switches mounted to the lock shaft and the lid detects that the
solenoid is in the specified position, and "Beep" sound is issued and the operation turns to stand-by status.
- When the START button is pressed, the live solenoid becomes non-live and the end of the solenoid enters
the hole of the movable handle. By so doing, the movable handle is fixed and at the same time, the
micro-switch is pushed by the end of the solenoid and the position of solenoid is detected to start the
operation.
(Cautions)
If the START button is pressed with the cover lock being incomplete, the caution sign "Lid'"
appears on the digital display of the control panel and the buzzer sounds. This is to inform that the
lid is not closed up to the normal position. Therefore, the cover handle must be pushed down until
the buzzer sound "Short Beep" is heard .
• When the "Lid'" display appears, the following causes are taken account.
• Handle is not pushed down completely.
Since the temperature in the chamber is high, repulsive force (force to open the lid) of the
chamber lid packing is too strong to push down the handle .
• The chamber lid packing is removed and the lid bites a part of it.
®About the "door" display
Lock shaft is closed when the cover is open (detection switch "ON"), the lock shaft opens once as the cover
closes (detection switch "OFF"), and it closes again (detection switch "ON") when the cover closes.
In order to detect adherence to ON of the lock shaft switch, it is checked by microcomputer that the lock
shaft opens and then closes (detection switch turns OFF and ON.), and if it was not detected that the switch
is OFF, "door" is displayed.
(Cautions)
If the START button is pressed without opening the lid immediately after the power is turned ON,
the "door" display appears, but this is not due to any trouble. Close the cover once and then press
the START button to start the operation.
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