Panasonic NN-C781JF Service Manual ▷ View online
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3. Check component by circuit tester.
1. How to check power transistors (Q701, Q702). To measure, suck
a solder from its legs completely unless faulse reading may
observe and mislead a troubleshooting. Measure across pins
between E-C, E-G, C-G, E-black lead, C-red lead of tester should
be infinite and may have some reading in reverse, it is normal.
Refer to attached table for normal reading.
2. DB701 Diode Bridge.
3. C704, C705 High voltage Capacitors. D702 and C705, D701 and
C704 are parallel connected therefore, remove component to
measure when diode is shorted.
4. D701, D702 High voltage Diodes.
a solder from its legs completely unless faulse reading may
observe and mislead a troubleshooting. Measure across pins
between E-C, E-G, C-G, E-black lead, C-red lead of tester should
be infinite and may have some reading in reverse, it is normal.
Refer to attached table for normal reading.
2. DB701 Diode Bridge.
3. C704, C705 High voltage Capacitors. D702 and C705, D701 and
C704 are parallel connected therefore, remove component to
measure when diode is shorted.
4. D701, D702 High voltage Diodes.
4. How to replace power transistors Q701, Q702 and
Bridge Diode DB701.
1. To remove Q701, Q702 and DB701 unsolder their legs first, next
remove a screw that holding the heatsink onto the PCB then
dtach the heatsink as shown below.
Sevice Hints: For easy solder removal, use one soldering iron to
heat a solder and use solder sucker iron to suck solder.
2. Make sure to replace both Q701 and Q702 at a time with the
same maker.
3. Make sure to apply heat conduction grease between transistor
and heat sink.
4. NO DUST SHOULD CAUGHT between heat sink and power
transistor unless if causes looseness of heat conduction and
insufficient cooling to blow components.
remove a screw that holding the heatsink onto the PCB then
dtach the heatsink as shown below.
Sevice Hints: For easy solder removal, use one soldering iron to
heat a solder and use solder sucker iron to suck solder.
2. Make sure to replace both Q701 and Q702 at a time with the
same maker.
3. Make sure to apply heat conduction grease between transistor
and heat sink.
4. NO DUST SHOULD CAUGHT between heat sink and power
transistor unless if causes looseness of heat conduction and
insufficient cooling to blow components.
5. Screw must be tighten securely.
6. Install the heatsink onto the PCB by a screw and
make sure to apply extra solder between legs and
PCB pattern so that it’s able to flow 15A or more
main current.
PCB pattern so that it’s able to flow 15A or more
main current.
Apply silicone grease
Make sure remove inverter PCB when continuity check
Do not test component when inverter PCB is installed
Do not test component when inverter PCB is installed
FORWARD
Some
Ω
∞
∞
∞
E-C
E-G
E-G
C-G
REVERSE
∞
∞
∞
∞
∞
FORWARD
Some
Ω
Some
Ω
∞
Some
Ω
REVERSE
∞
∞
∞
∞
∞
∞
∞
~ - +
~ - -
~ - ~
+ - -
BETWEEN
TERMINALS
FORWARD
REVERSE
∞ infinite
Circuit tester employed
lower voltage battery
Circuit tester employed
lower voltage battery
Several k ohm to several
hundred k ohm will be
observed
Circuit tester should
employed more than 9V
battery
hundred k ohm will be
observed
Circuit tester should
employed more than 9V
battery
∞ infinite
it does not matter by
internal battery voltage
it does not matter by
internal battery voltage
A-K
HEAT SINK
Heat sink
Tighten screw securely
Clean Surface and
Apply silicone grease
Apply silicone grease
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7. Apply extra solder onto Q701 and Q702 legs and
printed foil pattern to be able to hold main large
current of more than 15A.
current of more than 15A.
For easy removal of solder, apply some solder first than suck it all.
8. How to test repaired Inverter PCB.
Warning:
Warning:
1. Do not test Inverter PCB with using any extention cable Open
gounding of inverter PCB is so DANGER.
2. Make sure to check no Bridge solder nor cold solder joint.
gounding of inverter PCB is so DANGER.
2. Make sure to check no Bridge solder nor cold solder joint.
1. Install Inverter PCB into oven with screws securely, plug in
CN701, CN702 and CN703.
2. Insert AC plug through the Amper meter with specified voltage.
NOTE: Current will be changed by the input AC voltage.
3. Operate the oven at High power setting for 1 minutes.
4. Read input current which should be within oven specification.
NOTE: Input current will be decreased after a certain cooking
period.
5. Adjustment is not necessary when replacing transistors, You may
adjust the preset volume control VR701 to meet the specified
input current when Transformer is replaced.
CN701, CN702 and CN703.
2. Insert AC plug through the Amper meter with specified voltage.
NOTE: Current will be changed by the input AC voltage.
3. Operate the oven at High power setting for 1 minutes.
4. Read input current which should be within oven specification.
NOTE: Input current will be decreased after a certain cooking
period.
5. Adjustment is not necessary when replacing transistors, You may
adjust the preset volume control VR701 to meet the specified
input current when Transformer is replaced.
How to test oven
Use
“Power check”
“Power check”
Check input current
Apply extra solder
Apply extra solder for large current flow
Base
or
Use
Ampare meter
Ampare meter
7.1 ~ 8.7A
4.4 ~ 5.8A
MAX AMPS AT BEGINNING
AFTER 10 MINUTES
AFTER 10 MINUTES
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HOW TO CHECK THE SEMICONDUCTORS USING AN OHM METER
INVERTER BOARD PARTS LIST (A606Y4V00GP)
C701
C702
C703
C704,C705
CN701
CT701
D701,D702
D703
D704,D705
D706
DB701
H.S.
IC702,IC703
IC801
L701
Q701
Q702
C806
Q703,Q704
Q705
R715
VR701
ZD701,ZD703,ZD704,ZD705
ZD702
T701
ECWF5104N300
ECQE2405T847
ECWF5454N300
ECWH30822JUA
AEEMXH00703WG
A66904T00AP
A6202-4N10T
AEDNERA3806
AEDNERA1506
MA196-(TA5)
AESTRBV6206
XTW3+12B
A66914T00AP
AEICP25011HL
AN9DB07SB
A50204T00AP
A691E4V10GP
A691E4V10GP
A691E4V10GP
XTN3+12B
2SC3311AQSTA
2SA1309AQSTA
AERGS215J452
AEVTZ6TLT102
AEDZ10ES2T1
AESZ12JS2T1
A609A4V00GP
1
1
1
2
1
1
2
1
2
1
1
2
1
2
1
1
1
1
1
1
2
1
1
1
4
1
1
CAPACITOR
POLYESTER CAPACITOR
FILM CAPACITOR
FILM CAPACITOR
CONNECTOR
TRANSFORMER
DIODE SI
DIODE SI
DIODE SI
DIODE SI
DIODE SI
SCREW
HEAT SINK
IC
IC
COIL
TRANSISTOR SI
TRANSISTOR SI
CAPACITOR
SCREW
TRANSISTOR SI
TRANSISTOR SI
RESISTOR
VARIABLE RESISTOR
ZENNER DIODE SI
ZENNER DIODE SI
TRANSFORMER
Ref.No.
Part No.
Part name & Description
Pcs/
Set
Remarks
0.1
µF, 500VDC
4
µF, 250VDC
0.45
µF, 500VDC
8200PF, 3KVDC
0.3A
0.5A
1A
MA196, 0.1A
15A, 600V
3*12 (FOR Q701)
PS2501-1, HL 4P
AESCGT60M303
AESPGT30J322
56PF TRANSISTOR (Q701,Q702) KIT
3*12 (FOR Q702)
2SC3311AQRS
2SA1309AQRS
4.5K
Ω, 15W
1K
Ω, 308
RD10ES2T1
RD12JS2
!
EXPLODED VIEW AND PARTS LIST
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EXPLODED VIEW
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