I went to the hardware store pulled a bunch of LED bulbs off the shelf. One of the bulbs found its way into the wrong box and had a significantly smaller screw base than your typical light bulb base. Because I wasn't paying attention to this as I was putting in all the bulbs, I inadvertently attempted to put in the bulb with the smaller base which tripped a breaker, causing all my power to go out. I switched all the breakers back on and my power came back, but now my light won't work. Did I destroy the fixture forever or is there something that I am missing here? It's wired up to a dimmer control if that is of any use here.

  • Yes, the short circuit probably ruined the dimmer control.
    – Dave Tweed
    Apr 19, 2015 at 0:16

1 Answer 1


TL;DR: The dimmer's toast. Replace it.

The short circuit or overload condition indeed likely smoked the switching element in the dimmer; modern dimmers use a special type of transistor-like switching element known as a triac to cut part of each half-cycle of the AC wave out in order to reduce the power being applied to the lamp. Unfortunately, triacs are very intolerant of short-circuits, and to make a short-circuit resistant dimmer would drive the dimmer makers out of business, so dimmers just let out the magic smoke whenever shorted (such as when a portable lamp is on a dimmer, and the bulb is broken).

  • You could add that the triac switching circuits used also do not like short circuits at all. Manufacturers could design dimmers with added short circuit protection but that adds to the cost of the dimmer and thus makes their product not able to compete with other cheaper products. Note that it is also common that dimmer equipped portable light fixtures will experience triac failure when an active ON light is knocked over and the mechanical shock breaks the filament. The hot filament ends fly around and can create shorts if they contact the opposite (continued)
    – Michael Karas
    Apr 19, 2015 at 17:28
  • (continued from above) support electrode in the bulb and thus take out the triac.
    – Michael Karas
    Apr 19, 2015 at 17:28
  • Indeed it was toasted. I replaced it and the new one works. Good call May 7, 2015 at 20:36

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