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Lamp step-down transformer is not working. How to repair it?

Discussion in 'Repairing Electronics' started by J_Nichols, May 17, 2017.

  1. J_Nichols

    J_Nichols Member

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    I found a lamp at home which is not working.

    I have used the multimeter to detect where the problem was coming from and it seems that the problem is coming from the transformer. It's a 220 to 12 volts transformer and I can read 220 in the input, but nothing in the output. So, something is not working fine within the transformer.

    I have only a multimeter, a LC meter and an amp meter as measuring instruments. My experience is very little with electronics.

    I have removed the insulation (mainly tape) and I have found something like a transistor. In the input it seems that there are 3 wires.
    One wire connected to 220 input wire, the second wire connected to the other input wire and the transistor and the third wire only connected to the transistor.

    Maybe the transistor is broken?
     
  2. MikeMl

    MikeMl Well-Known Member Most Helpful Member

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    Likely an over-temperature fusible link embedded in the transformer winding. If blown, question is why?
     
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  3. Colin

    Colin Member

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    Short it out. It has just gone faulty.
     
  4. dave

    Dave New Member

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  5. ci139

    ci139 Active Member

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    you can always rewind secondary to your like -- "a bit" more difficult with primary that has to be done considering not over stressing the thin fragile wire while winding it , winding it so that it would not break from misc. thermal expansion , winding it so that it would have least parasitic losses
     
  6. J_Nichols

    J_Nichols Member

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    The lamp has like 2 antennas (like radio ones) that serves to set the height of the lamp. If touched together, they can be shorted. So I think a short caused the problem.

    I have took different measurements in the lamp and the problem is in the transformer. I can read 220Volts in the input, but nothing in the output. All the other contacts work good.

    I have opened the transformer and I have found a small electrical component that I have no idea about what it is:
    is it a fuse? is it a transistor?
    https://gyazo.com/066f852dd37a2112742c94217bceb7e8
     
  7. ci139

    ci139 Active Member

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