Thermo Scientific 3051 Series, Operating Manual And Parts List

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The 3051 Series controllers are factory calibrated near the center of the
oven's operating range and will usually remain reasonably accurate over a
long period of usage. However, should the accuracy diminish with time, or
should the user require greater accuracy at a particular temperature setting,
the controller may be recalibrated.
The temperature controller has high and low temperature range
adjustments located under the skirt of the set temperature dial.
To recalibrate the controller, perform the following procedures:
1. Place a calibrated thermometer (preferably traceable to NIST
standards) in oven chamber.
2. Rotate temperature dial full counterclockwise (CCW).
3. The dial line should point to 20°C. If not, loosen the setscrew holding
the dial on its shaft. Rotate shaft until dial line points to 20°C, then
re-tighten set screws.
4. Press oven Power switch to ON (1) position.
5. Rotate temperature dial to 40°C. Heat indicator will come on full,
then begin to cycle on/off as the oven approaches final temperature.
6. After the heat indicator begins cycling, allow an additional 30 minutes
for the oven to achieve a final, stable temperature.
7. Carefully remove the temperature dial knob without rotating it.
(continued)
Precision Standard Oven 5-3 Thermo Scientific
Section 5
Operation
Calibration
Low Adjust
High Adjust
Figure 5-1. High and Low Temperature Range Adjustments