Thermo Scientific 3051 Series, Руководство по эксплуатации и список запасных частей

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1. Disconnect power cord from the electrical outlet.
2. Open the chamber door. Carefully remove and retain hardware from
door hinges (case side). Set door aside.
3. Slide the oven back until the front of the bezel (control panel) is at
least three inches from the edge of the bench top.
4. Prop up the oven front by placing a shim under each front foot. Use
shims between one and one-half and two inches in thickness.
5. Remove two screws securing bezel from bottom of oven.
6. Grasp bezel and pull bottom outward. Bezel will disengage from fascia.
Lay bezel on benchtop in front of oven.
7. Remove thermocouple wires from 2-terminal connector by loosening
two securing screws.
8. Loosen 2 screws at lower front of oven chamber that secure the safety
shield. Lift shield upward to free bottom shelf. Pull bottom shelf
outward to access the thermocouple.
9. On back wall of oven, locate the two clips, which hold thermocouple
in place. Remove thermocouple from clips.
Note Observe position in terminal for each lead. When re-connecting, be
certain to observe polarity. Compare with polarity indication on controller
housing. For thermocouples, the red wire is negative and yellow positive.
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10. Pull thermocouple forward and out through side hole in oven chamber.
11. Carefully feed leads of replacement thermocouple through side hole in
oven chamber and oven insulation.
12. Reaching into electronics compartment, pull thermocouple leads into
place.
13. Generally reverse Steps 1 through 8 to complete installation of new
thermocouple and reassemble oven.
14. Align thermocouple properly in clips near back wall of oven. The end
of the thermocouple should protrude only 1/4" over the left side of the
oblong hole in the heater cover. This will give the best control. If
during Calibration, more adjustment is needed on the on the HI range
potentiometer, set the sensor so only 1/8" is over the oblong hole.
15. Slide lower shelf back and reinstall the safety shield. Fasten shield
under screws that attach the heater cover.
6-6 Precision Standard Oven Thermo Scientific
Section 6
Service
Replacing the Control
Thermocouple