Part Replacement Procedure - Panasonic NN-A574SBBPQ Service Manual

9 Part Replacement Procedure

9.1 Magnetron
1. Discharge the high voltage capacitors on the
inverter circuit.
2. Remove the 1 screw holding air guide A.
3. Remove the 2 screws holding the tie bar.
4. Remove the oven lamp and lead wire harness from
air guide A.
5. Remove the air guide A.
6. Disconnect the 2 high voltage leads from the magn-
etron.
7. Remove the 4 screws holding the magnetron.
NOTE: After replacing the magnetron, tighten the
mounting screws so there is no gap between the
waveguide and the magnetron, this prevents
microwave leakage.
Caution
When replacing the magnetron, ensure that the
antenna gasket is in place.
The magnetron used for this model is unique for the
inverter power supply system. Only fit the magnetron
listed in the service manual parts list.
AIR GUIDE A
figure 6 Removal of the magnetron
9.2 Inverter circuit
1. Discharge the high voltage capacitors.
2. Remove 2 screws holding the tie bar.
3. Unplug the H.V. Lead wires from the magnetron.
Note
4. Remove the 1 screw holding the earth wire to the
magnetron.
5. Remove the connector CN701 and CN702 from the
inverter PCB.figure 8
6. Remove the 2 screws holding the inverter support-
base to the oven chassis.
7. Carefully remove the inverter circuit board and sup-
port base from the oven.
8. Remove the air guide E.
9. Remove the 4 screws holding the inverter circuit
board to the inverter support base. Figure 7
When replacing the inverter circuit
1. Check the grounding plate is in place.
2. Securely tighten the grounding plate screw through
the side of the oven chassis.
3. Connect the 3 lead wire plugs into the correct sock-
ets.
4. Ensure there is enough space between the heat sink
and other components. Check that no lead wires are
touching the aluminium heat sink.
figure 7 Removal of the inverter PCB.
figure 8 Disconnecting the PCB locking plug.
12
Caution
H.V.INVERTER(U)
GROUNDING BRACKET
INVERTER SUPPORT BRACKET