Thermo 3920, Руководство по эксплуатации и техническому обслуживанию

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5.3 Replacing the Temperature Sensor
1. Locate the probe mounting plate in the center of the
right side of the incubator interior.
2. Open the mounting plate by removing the screws that
hold it in place.
3. Locate the sensor mounted on the inside of the panel in
a black housing. Note the angle of the probe.
4. Grasp and unplug the probe from the probe cable.
5. When replacing the sensor, be sure to mount the probe at
the same angle as it was originally mounted.
5.4 Removing the Top Section
If it becomes necessary to remove the top of the incubator
for moving it through low doorways, refer to the points follow-
ing, then use the indicated procedure:
• Read the instructions completely before starting the
removal process.
• Provide adequate space and sufficient lighting to perform
the work.
• Disconnect the inlet water supply and the drain.
• Before lifting the top section from the incubator, provide
carpenter’s horses or another suitable support arrangement
so that the underside of the top is suspended.
Procedure:
1. Remove all test material from the incubator chamber.
2. All temperature-sensing probes are mounted on a probe-
mounting bracket on the right side of the incubator
chamber. Remove the nuts securing the bracket and
then remove the probes from the bracket. Note the loca-
tion and configuration of the probes.
3. The sensing bulb capillaries are routed behind the duct
sheet, up to the access port at the top of the unit and
behind the control panel.
Note: Route all the probes between the duct sheet and the out-
side wall of the chamber so that when the top is raised, all
probes will move freely up and out. Do not kink or bend the
capillaries.
4. Open the control panel by removing the two screws
located on the left side of the control panel.
5. Loosen the top gasket around each of the air exhaust
vents by turning the screw.
6. Remove the eight screws from the top cover of the incu-
bator.
7. Remove the four screws from each of the vent caps on
the top cover of the incubator. The top cover can now be
removed.
Section 5 - Service
Servicing must be performed by qualified service
personnel only!
De-energize all potential sources of energy to this
unit and lockout/tagout their controls. (O.S.H.A.
Regulation, Section 1910-147.)
5.1 Access to the Electrical Components
To gain access to the electrical components, remove the
two screws located on the left side of the control panel with a
phillips screwdriver. The control panel is hinged and will swing
open.
5.2 Replacing the Overtemp/Undertemp Probe and
Thermostat
1. Remove the incubator ceiling by remove the screws
holding it in place.
2. Remove the top three screws from the top of the right
duct cover.
3. Lean the duct sheet out, and remove the Permagum seal
from around the probe access hole.
4. Remove the 15” copper capillary overtemp probe by
extracting the two plastic clips that hold the probe in
place.
5. Open the control panel by removing the two screws
located on the left side of the control panel.
6. Pull the overtemp probe up through the access hole and
into the control panel.
7. Follow the wires from the probe to the thermostat
mounted on the control panel. Clip the plastic ties hold-
ing the overtemp cable to the existing wiring.
8. Pull the overtemp knob on the control panel off.
9. Remove the two screws that hold the overtemp assembly
to the control panel.
10. Disconnect the two wires from the back of the thermo-
stat assembly.
11. Pull the entire assembly out of the panel, and remove the
unit.
12. Replace the thermostat and probe.
Note: Reseal the probe access hole with Permagum, and retie
the overtemp cable to the existing wires after replacing the
probe.
Model 3920 _______________________________________________________________________________Service
5 - 1