(TROUBLE 3) No microwave oscillation even though fan motor rotates.
CONDITION |
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| CAUSE |
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REMEDY
No
microwave oscillation
Continuity |
Check continuity of high |
voltage fuse |
Replace high voltage fuse |
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| Continuity |
Check continuity of high |
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voltage capacitor terminals |
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with wires removed |
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Check continuity of high voltage |
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| Continuity in |
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rectifier in forward and backward |
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direction with DC megger |
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| Continuity |
Connect megger leads to mag- |
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netron terminal and magnetron |
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body |
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| 0 Ω or ∞ |
Check resistance of primary and |
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secondary coil of high voltage |
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transformer |
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| No |
Check continuity of magnetron |
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| Continuity | ||
with wires removed |
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| No |
Check continuity of filament termi- |
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| Continuity | ||
nal of high voltage transformer |
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| 0 V |
Check D.C. voltage being sup- |
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plied to RELAY (RY1) coil |
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| Approx |
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| 15 VDC |
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Defective high voltage trans- former
Defective high voltage rectifier
Defective mag-
netron
Defective high voltage trans- former
Defective mag-
netron
Defective high voltage trans- former
Defective touch
control circuit
Faulty
contacts or
RELAY (RY1)
or open
relay coil
Replace
Replace
Replace
Replace
Replace
Replace
Replace
Replace
19
