Shellab SVAC9-2 - Manual (Page 22)

22 | P a g e
OPERATION (CONTINUED)
The difference between the reference device and oven display is called an offset.
Examples of offsets:
Reference Sensor
Reading
Watlow Temp.
Display
Offset
Value
152°C 150°C 2
148°C 150°C -2
8. To enter the temperature offset into the Watlow Controller, press and hold both Up
and Down Arrow Button simultaneously for approximately three (3) seconds until “A1”
appears in the Upper Display and “Oper” appears in the Lower Display.
9. Push the green Advance Button repeatedly unit “i.CA” appears in the green middle
display and a number value in the red top display.
10. Adjust the number value in the top display using the Up or Down Arrow Buttons to
match the offset value.
11. Once the Offset Calibration Number is entered, push the Reset Button repeatedly to
exit the calibration, save the set point, and return to the Home Page. The current
temperature will show on the top display and the set point in the bottom.
12. Repeat steps four through seven (4 – 7).
13. If the temperature readings of the display and the reference device still do not match or fall
close within your lab or production protocol after three calibration attempts, contact
Sheldon Technical Support for assistance.
S ETTING THE O VER T EMPERATURE L IMIT C ONTROL
After calibrating the oven perform the following steps to set the Over Temperature Limit Control
system for use.
1. If you have not already done so, turn the Set Over Temperature Limit control dial clockwise
to the maximum position. This allows the oven to stabilize at its current set point without
interference.
2. Turn Over Temperature Limit dial counterclockwise slowly until the Watlow Controller turns
off.
3. Turn the Over Temperature Limit Control approximately 1/8 inch (3mm) clockwise and then
push the Reset Button. If the Watlow turns on and remains powered, the Over Temperature
Limit is set.
4. If the Watlow shuts off, turn the Over Temperature Limit control clockwise another 1/8 inch
(3mm) clockwise and push the Reset Button. Repeat this process until the Watlow remains
powered.
5. The OTL should now be set approximately 1
˚C above your temperature set point.