Question about Panasonic NN-C994S Convection/Microwave Oven

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I replaced low voltage transformer on PCB of display board , and when i started for a while all was ok but next day when i started microven once again this transformer got opened and my oven stopped working, on transformer there are 2 terminal marked P1 and P2, can some one explain why this is happening , is it correct to loop P1 AND P2 externally(as i believe this are looped inside transfomer,and due to some reason gets opened) Please guide on possible cause and rectification

Posted by rajendra panchal on


2 Answers


I had looped externally P1 and P2 and now it is working , to assure myself I also checked current in primary of transformer it was measured to be from 300 mA to 600 mA when I started to use microoven. For safety I had now fixed 2 Amp fuse between P1 and P2. Is that all ok. To add I checked all voltages mentioned on PCB viz. 30volt, 5 volt etc which on measuring were found almost ok. Any comments please

Posted on Mar 29, 2007


William Miller

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There is something on the secondary side which is drawing too much current. I would check all electrolytic capacitors, zener diodes, transistors, and voltage regulators.

Posted on Mar 29, 2007


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