Ovention MiSA-a12, Инструкция по установке, эксплуатации и обслуживанию

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Form No. OVMISAM-0321
30
To avoid serious injury or death, read all
IMPORTANT SAFETY INFORMATION
at the front of this manual.
IMPORTANT NOTE
Many of the service procedures in this section require removal
of insulation to access the parts. All illustrations are shown with
insulation removed for clarity.
Capacitor
There are two capacitors in the unit. Perform the “Testing/
Troubleshooting” on both, and replace as necessary.
Testing/Troubleshooting
DANGER! Completely shut down and unplug oven
before proceeding. Refer to “Shutdown” procedure.
DANGER! Capacitors must be discharged before
proceeding.
• Disconnect all wires from the capacitor, and measure the
capacitance with DMM (0.97uF ±3%). If the measurement
is not within tolerance, replace the capacitor.
Replacement Procedure
1. Completely shut down and unplug the oven. Refer to the
“Shutdown” procedure in the OPERATION section.
2. Remove the top panel. Refer to the “Removing the Top
Panel” procedure in this section.
3. Discharge both capacitors. DANGER! Capacitors must
be discharged before proceeding.
4. Disconnect all lead wires from the capacitor.
5. Remove the two (2) hex nuts that secure the capacitor
mounting bracket and the capacitor to the transformer
support brace. Remove the mounting bracket and capacitor.
6. Install the new capacitor by reversing the steps above.
Hex
Nut
Capacitor Mounting
Bracket
Capacitor
Capacitor
Transformer
Support
Brace
Transformer
There are two transformers in the unit. Perform the “Testing/
Troubleshooting” on both, and replace as necessary.
Testing/Troubleshooting
DANGER! Completely shut down and unplug oven
before proceeding. Refer to “Shutdown” procedure.
• Measure the resistance of the transformer using an
ohmmeter. If the resistance measurements are not within
range, replace the transformer.
a. Disconnect all lead wires from the transformer.
b. Discharge both capacitors. DANGER! Capacitors must
be discharged before proceeding.
c. Measure the resistance using an ohmmeter:
0 to 208 = 0.55 ohms ±20%
0 to 230 = 0.65 ohms ±20%
High voltage = 57.5 ohms ±20%
0 to ground = open
208 to ground = open
230 to ground = open
Filaments to ground = open
Replacement Procedure
1. Completely shut down and unplug the oven. Refer to the
“Shutdown” procedure in the OPERATION section.
2. Remove the top panel and left side panel. Refer to the
appropriate procedures in this section.
3. Discharge both capacitors. DANGER! Capacitors must
be discharged before proceeding
4. Disconnect all lead wires from the transformer.
5. Remove the four (4) hex nuts that secure the transformer
to the transformer support brace.
NOTE: When replacing the front transformer, the rear
transformer will need to be removed to provide
clearance.
6. Install the new transformer by reversing the steps above.
Transformer Support Brace
Rear
Transformer
Thermocouple Front Transformer
Hex
Nut
SERVICE PROCEDURES