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smoke/pow/eek/always use a fuse!!--need help w/ switch!?

Discussion in 'DIY' started by rogerfederer, Mar 19, 2017.

  1. whoaru99

    whoaru99 Epic Member

    Messages:
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    Location:
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    The gauge of your wire needs to be, at a minimum, commensurate with the fuse protection in the circuit.

    I suggest a main fuse first thing right at the battery to protect the entire power circuit from meltdown if there is a downstream short. Just be sure the wire gauge is large enough so the fuse blows before the wires get hot.
     
  2. petehall347

    petehall347 the brandy coffee man Subscriber

    Messages:
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    uk.. the middle bit
    i will generally fit a reverse polarity diode and a fuse so damage can only be caused to the fuse and sometimes the diode if unlucky .. diode goes right across power supply fuse goes between battery and diode .
    another way if you can be bothered and have correct supply is use a bridge rectifier then it doesn't matter which way you connect the battery . i learnt that from a Philips radio back in the the late 1970.s . it was fitted as standard .
     
  3. whoaru99

    whoaru99 Epic Member

    Messages:
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    The bridge rectifier works pretty foolproof if the circuit will tolerate the added voltage drop across the diodes.

    That said, a little color coding and a fuse goes a long way.
     
  4. petehall347

    petehall347 the brandy coffee man Subscriber

    Messages:
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    Location:
    uk.. the middle bit
    reverse polarity diode is a must have in combination with a fuse .. otherwise fuse will blow after damage is done ...
    just for example ...[​IMG] [​IMG]
    [​IMG]
     
  5. whoaru99

    whoaru99 Epic Member

    Messages:
    37,376
    Location:
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    That's fine, if the consideration is connecting the battery backward at the left side of the illustration. It doesn't help if you connect backward to the amplifier at the right side, which is what I understand was the problem in this csse.
     
  6. rogerfederer

    rogerfederer AK Subscriber Subscriber

    Messages:
    3,649
    Location:
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    OK, good news: the new board and switch arrived. wired it up with a 10amp/250volt fuse. works! sounds great too:beerchug:

    update: didn't see last 2 posts before my report (above); will look into diode
     

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