Fisher Scientific 282A, Инструкция по эксплуатации, Страница: 13 / 25

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Temperature/Pressure Offsets
When the oven reaches a stable operating condition, the display temperature should indicate the actual center
chamber temperature (+/- 2.0°C). In the event a more accurate display reading is needed, the offset parameter,
located in the MAIN MENU, can compensate for the error. To enter an offset value, press the MENU key until the
upper display window shows ADJT (adjust temperature) then press UP/DOWN arrow keys to enter an offset for the
display temperature. Press the MENU key 5 times to return to the default display or wait for 2 seconds and
control will shift automatically.
EXAMPLE: The oven is temperature is set for 200°C. After it has reached a stable state (usually 2½ hours for
200°C) the actual temperature of the oven center, as read by a certified thermometer, is 203°C. The oven display
shows 200°C. Entering a +3 for the ADJT parameter will move the display to agree with the actual oven
temperature.
NOTE: Adjusting the offset only changes the display temperature. It does not alter the controller operation.
The vacuum display can be adjusted in the same way. In the event the displayed chamber pressure is not
accurate, press the MENU key until the upper display window shows ADJP (adjust pressure). Use the UP/DOWN
keys to enter the desired offset. Press the MENU key four times to return to the default display or wait for 2
seconds and control will shift automatically. The displayed chamber pressure will be updated with the offset
value.
Setting the Time and Day
To set the time and day press the MENU key until the upper display shows TSET (time set). Press the SET key
and use the UP/DOWN arrow keys to adjust the hour of the day. When the current hour is displayed enter it by
pressing the SET key again. Use the UP/DOWN arrow keys to adjust the minutes. When the correct minutes are
displayed, press the SET key. Finally, days of the week can also be adjusted by pressing the UP/DOWN arrow
keys. Press the SET key again to enter the day of the week.
PROGRAMMING THE OVEN
The oven controller is capable of handling 8 instructions per day, 7 days a week. Programming the controller is
not difficult. Table 7, listed as
MENU 6 – Program Edit Mode , provides step by step instructions for setting the
control temperature and/or vacuum pump operation at any given time of day or day of the week. Use Table 7 in
conjunction with the following description when programming the oven controller
To enter the
Program Edit Mode press the MENU key until the upper display shows PSET. The upper display will
then show MON1, indicating the first step in Monday. Use the UP/DOWN arrow keys to step through to the
current day of the week. When the desired step is reached press SET. Use the UP/DOWN arrow keys to adjust
the starting hour of the current step, press SET to select the desired hour. Repeat for minutes, temperature and
vacuum pump operation. The next prompt (N ?) asks the user to copy the current step to the remaining steps in
the day. Use the UP arrow key to select Y (yes), or leave as is and select no by pressing the SET key. The upper
display will then shift to the next step, MON2 (if MON1 was the previous step). Repeat this procedure for entering
new steps.
If a step was copied to the end of the day, that same day can also be copied to the end of the week. To do this,
press the MENU key when the next step appears in the upper display window. At that point, press the MENU key.
The upper display will show COPY, while the lower display shows NO. Use the UP arrow key to change the NO to
YES. Press the SET key and the previous day’s program is copied to the end of the week.
NOTE: The program week begins on Monday and ends on Sunday.
Sample Program:
Monday:
1.
Evacuate chamber and operate at 100°C for 5 hours starting at 8AM. Maintain less than 5 in Hg during the 5
hours.
2. Increase temperature to 150°C and operate for 2 hours. Maintain same chamber pressure.
3. Shut down oven for remainder of day.
Tuesday:
Repeat steps from Monday except step 2. Have oven shut down after 100°C operation.
Wednesday: