Panasonic Nn St452w User Manual

4.3. Low voltage transformer
and/or power relays (RY1,
RY2)
CAUTION:
Be sure to ground any static electric charge built up in
your body before handling the DPC.
 1. Replace D.P.C. board.
(A) Using solder wick or a desoldering tool and 30W
soldering iron carefully remove all solder from the terminal
pins of the low voltage transformer and/or power relays.
CAUTION:
Do not use a soldering iron or desoldering tool of
more than 30 watts on D.P.C. contacts.
(B) With all the terminal pins cleaned and separated...

 6. Replace other components.
To re-install components:
NOTE:
After replacement of the defective component parts
of the door, reassemble it properly and adjustment
so as to prevent an excessive microwave leakage.
Adjustment of the door assembly (Refer page 17).
 7. Place the hole of hinge A into the door’s upper hinge pin.
 8. Use your left index finger to support the door’s lower hinge
pin while guiding the door’s hinge A into the cavity slot.
Then lower your finger to seat the door onto the hinge....

4.6. Turntable motor
 1. Remove the motor cover by breaking off at the 8 spots
indicated by arrows with a cutter or the like.
NOTE:
After removing the motor cover, be sure that cut
portions are properly trimmed or bent to the inside
so that no sharp edges will be exposed to outside.
 2. Disconnect 2 lead wires connected to the turntable motor.
 3. Remove the turntable motor by removing screw.
NOTE:
After reinstalling the new turntable motor and
reconnecting the 2 lead wires, reinstall the motor
cover by...

4.8. Inverter power supply
CAUTIONS
1. Always leave the grounding plate in place.
2. Always securely tighten the ground screw through the bottom of the
chassis (base).
3. Securely connect 3 lead wire connectors.
4. Make sure the heat sink has enough space (gap) from the oven.
Take special care not to dress any lead wire over the aluminum heat
sink because it is hot.
 1. Discharge high voltage charge.
 2. Remove the H.V.lead wire from magnetron terminals.
 3. Disconnect 2 connectors from CN701 & CN702 on...

WARNING
1. High voltage is present at the output terminals of the High Voltage
Inverter (U) including aluminum heat sink during any cook cycle.
2. It is neither necessary nor advisable to attempt measurement of the
high voltage.
3. Before touching any oven components, or wiring, always unplug
the power cord and discharge the high voltage capacitors (see page
8).
5.1. Primary, Secondary Latch
Switch interlocks & Power
Relay RY1
 1. Unplug lead connectors to Power Relay RY1 and verify
open circuit of the...

5.5. Inverter power supply (U)
DO NOT try to REPAIR H.V. Inverter power supply
(U).Replace complete H.V. Inverter(U) Unit.
WARNING: HIGH VOLTAGE
Test if failure codes H95, H97 or H98 appear when performing
the following procedure. It is recommended to use an AC line
input current ammeter for testing.
Test 1
 1. With the oven unit’s AC power supply cord is unplugged
from the wall outlet, unplug the 2 pin H.V. connector CN703
from the magnetron tube.
 2. Place 1 liter of water load into oven cavity.
 3....

6.1. Adjustment of primary latch
switch, secondary latch switch
and short switch.
 1. Mount the Primary latch switch, the Secondary latch switch
and the Short switch to the door hook assembly as shown
in illustration.
NOTE:
No specific individual adjustments during
installation of the Primary latch switch, Secondary
latch switch or Short switch to the door hook are
required.
 2. When mounting the door hook assembly to the oven
assembly, adjust the door hook assembly by moving it in
the direction of the...

7 TROUBLESHOOTING GUIDE
DANGER: HIGH VOLTAGES
1.DO NOT RE-ADJUST PRESET CONTROL on the H.V.Inverter (U).It is very dangerous to repair or adjust without proper test equipment
because this circuit generates very large current and high voltage. Operating a misaligned inverter circuit is dangerous.
2.Ensure proper grounding before troubleshooting.
3.Be careful of the high voltage circuitry, taking necessary precautions when troubleshooting.
4.Discharge high voltage remaining in the H.V.Inverter (U).
5.When...

7.2. (Troubleshooting) Other problems
SYMPTOMCAUSECORRECTIONS
1.Oven is dead.1.Open or loose lead wire harness
Fuse is OK.2.Open thermal cutout / thermistorCheck thermal cutout is defective.
No display and no operation at all.3.Open low voltage transformer
4.Defective DPC
2.No display and no operation at all.
Fuse is blown.1.Shorted lead wire harnessCheck adjustment of primary, secondary latch
switch and short switch including door.
2.Defective primary latch switch (NOTE 1)
3.Defective short switch (NOTE...

7.3. Troubleshooting of inverter circuit (U) and magnetron
This oven is programmed with a self diagnostics failure code system which will help for troubleshooting. H95, H97, H98 and H99
are the provided failure codes to indicate magnetron and inverter circuit problem areas. This section explains failure codes of H95,
H97, H98 and H99. First, you must program the DPC into TEST MODE,For SD452W model:press Clock
button once→press
Timer
button once→press Startbutton once→press 1000W/600Wbutton once,For...