10.4. Trouble related to Digital Programmer Circuit
SYMPTOM
STEP
CHECK
RESULT
CAUSE/CORRECTIONS
No display when oven is first plugged
in
1
Fuse pattern of D.P.C.
Normal
→
Step2
Open
Replace D.P.C. or Fuse Pattern
2
Low voltage transforment (L.V.T.)
secondary voltage
Abnormal 0V
L.V.T.
Normal
→
Step3
3
IC1 pin 13 voltage
Abnormal
IC10
Normal=5V
IC1, Display
No key input
1
Touch switch continuity
Abnormal
Touch switch
Normal
IC1
No beep sound
1
IC1 pin 62 voltage
Abnormal
IC1
Normal=5V
BZ210, Q210
No microwave oscillation at any
power
1
IC1 pin 27 voltages while operation at high
power
Abnormal
IC1
Normal=5V
→
Step2
2
Collector of Q220 voltage
Abnormal
Q220 and/or Q221, Q225, Q227
Normal 0.7V
→
Step3
3
Short circuit between collector of Q220
and emitter of Q225
Still not turn on
RY1
RY1 turns on
Q220 and/or Q221, Q225, Q227
Dark or unclear display
1
Replace display and check operation
Normal
Display
Abnormal
IC1
Missing or lighting of unnecessary
segment
1
Replace IC1 and check operation
Normal
IC1
Abnormal
Display
H95/H97/H98 appears in window and
oven stops operation.Program High
power for 1 minute and conduct
following test quickly, unless
H95/H97/H98 appears and oven
stops
1
Unplug CN702 (2 pin) connector and
measure voltage between terminals
Abnormal=0V
1. Latch Switch
2. D.P.C. /Power Relay
Normal=120V
→
Step2
2
Unplug CN701 (3 pin) connector and
measure pin1 voltage of D. P. C. CN3
Abnormal=0V
D.P.C.
Approx. AC 3V
Magnetron
24
NN-SD372S
Содержание NN-SD372
Страница 2: ...2 NN SD372S ...
Страница 3: ...3 NN SD372S ...
Страница 5: ...1 FEATURE CHART 2 CONTROL PANEL 5 NN SD372S ...
Страница 6: ...3 SCHEMATIC DIAGRAM 6 NN SD372S ...
Страница 19: ...9 4 At least once a year have the radiation monitor checked for calibration by its manufacturer 19 NN SD372S ...
Страница 26: ...10 7 How to check the semiconductors using an OHM meter 26 NN SD372S ...
Страница 27: ...11 EXPLODED VIEW AND PARTS LIST 11 1 EXPLODED VIEW 27 NN SD372S ...
Страница 33: ...12 DIGITAL PROGRAMMER CIRCUIT 12 1 SCHEMATIC DIAGRAM 33 NN SD372S ...
Страница 34: ...34 NN SD372S ...