Will switching a light bulb on and off blow it?

Question

Hello All,

My parents used to say that if you switched a light on and off really fast - or any electronic appliance for that matter - that you would blow it. Can anyone tell me if that really is the case and why?

R

Answer 1

Incandescent bulbs often blow when they are first turned on due to the rapid heating from the cold state. Once on, flashing is relatively benign as the filament hasn't really cooled down yet. Consider most cars (except very new ones with LED signals) use incandescent bulbs and flash them repeatedly for our turn signals. My personal experience is that these don't blow any more often that my headlights which don't flash.

Other lighting types I probably wouldn't recommend doing it.

Most appliances won't hold up well. (Won't bother a blender, some have pulse modes as desgined.) If the have motors or compressors there's inertial loads compression cycles and a host of other detrimental things that can happen with rapid cycling. An oil burner cycled rapidly might build up a volume of unburnt atomized fuel and have an explosive effect if toggled in this manner. Electronic devices won't be able to complete their startup self-tests. The possibilities are many.

Answer 2

A bulb will usually blow when it is turned on not during the period the light is on. The reason for this is that there is a surge of electricity through the filament when it is turned on which is enough to cause it to break if it is weak.

Answer 3

You can sometimes blow the fuse or trip the breaker. I did it once with an air conditioner in a hotel.

Answer 4

Yes its possible because its a heat thin and over time the quick changes in temp could bloww it.

Answer 5

can't tell you why but yes it does happen... i've done it(not on purpose)