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My PCB transformer primary is always blowing off what could be problem

I tried to replace PCB transformer the one which is behind display board. but always primary blows off. I suspect some sensor to be faulty viz. humidity/temp sensors. Can someone help to locate it and anyone has link to service layoout drawing please

Posted by rajendra panchal on

  • rajendra panchal Apr 10, 2007

    Primary voltage is correct and even rating of transformer is correct.
    When i replace this transformer with new one , it worked for few days and I even measured all voltages at each point in secondry side , rely out any components failure.
    Now, only suspection remains is any component connected before primary side. Hence i need to know how this temp. sensor is connected , can u provide me general wiring diagram on microver close to model NNN -C 2000P panasonic



1 Answer

William Miller

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Is your line voltage correct? That needs to be measured, perhaps even monitored. Is it possible you have installed 120 volt replacements into a 220 volt model? Otherwise, there is a component shorted on the control board, such as a rectifier diode, zener diode, filter capacitor, or transistor. This would call for old-style troublehsooting. It's possible you have a bad sensor, but I doubt it. They could be disconnected or bypassed for test purposes.

Posted on Apr 10, 2007


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I recommend that you bookmark that link to your favorites.

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