Resettable Fuse

Discussion in 'General Electronics Chat' started by RodneyB, Oct 26, 2014.

  1. RodneyB

    Thread Starter Active Member

    Apr 28, 2012
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    I have been testing a 1 Amp resettable fuse on a 12 Volt supply. The supply cuts off instantly when I put a dead short on the output. However I am worried that the resettable fuse gets VERY hot. How long will it last with a dead short?
     
  2. bertus

    Administrator

    Apr 5, 2008
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    Hello,

    What kind of resetable fuse are you using ?
    The polyfuse are working on heating by overcurrent .
    The heating will raise the resistance of the polyfuse .
    There are also mechanical resetable fuses .

    Bertus
     
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  3. #12

    Expert

    Nov 30, 2010
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    I found a shorted car door lock switch that had been under safety lock out with a polyfuse for months, and it was still working when I found the fault. So, there you are. These things can safely hold in overload condition for months.
     
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  4. RodneyB

    Thread Starter Active Member

    Apr 28, 2012
    633
    13
    Its a poly fuse

    I have attached the datasheet from the supplier
     
  5. bertus

    Administrator

    Apr 5, 2008
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  6. MrChips

    Moderator

    Oct 2, 2009
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    The polyfuse will reach an equilibrium temperature and resistance where just the right amount of current conducts in order to maintain a given temperature.
     
    Last edited: Oct 26, 2014
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