Frequently switching a lamp ON and OFF in short time reduced bulb life?

[kenny1999]

I had a lamp that was good for 10 years but two years ago it was burnt out, I replaced it and in this two years we have a naughty kid playing with it, it is burnt out recently again. Is it likely due to his behavior (switch it ON and OFF within short time) or quality of light bulb in recent years not as good as that of the past?

 

[Baluncore]

Is it a filament lamp or LED?

 

[anuttarasammyak]

You were so lucky to use one light bulb for ten years. Light bulb is less popular today than it used to be so the motivation in production to keep or improve quality might have gone down. Why do not you think of replacing it with LED ?

 

[sophiecentaur]

Is it likely due to his behavior (switch it ON and OFF within short time) or quality of light bulb

As a filament spends time at high temperature ('white hot') the surface slowly boils away and coats the inside of the glass envelope. Impurities and thermal cycling can affect the strength and cause local hotspots which will be where the filament finally starts to 'burn out'. Rapid heating due to the current surge can cause expansion and stress and that's when they tend to go. Your delightful young relative could be partly to blame but ten years is a good innings for a bulb. Don't write him out of your Will.

When I played with light switches as a kid I was told "You'll fuse the lights." It sometimes blew a fuse after a few rapid doses of surge current. Repairing a wired fuse was (rightly) beyond a lot of people in those days; life is much easier now, with a reset button.

Despite the claims of longevity for early LEDs, I used to find they just didn't last very long. They are a lot better these days but heat can still affect them (built with a lot of plastic).

Ordinary filament bulbs are not officially available in UK any more.

 

[kenny1999]

You were so lucky to use one light bulb for ten years. Light bulb is less popular today than it used to be so the motivation in production to keep or improve quality might have gone down. Why do not you think of replacing it with LED ?

I'd like to but our house is old, so using new kind of lamp wil

As a filament spends time at high temperature ('white hot') the surface slowly boils away and coats the inside of the glass envelope. Impurities and thermal cycling can affect the strength and cause local hotspots which will be where the filament finally starts to 'burn out'. Rapid heating due to the current surge can cause expansion and stress and that's when they tend to go. Your delightful young relative could be partly to blame but ten years is a good innings for a bulb. Don't write him out of your Will.

When I played with light switches as a kid I was told "You'll fuse the lights." It sometimes blew a fuse after a few rapid doses of surge current. Repairing a wired fuse was (rightly) beyond a lot of people in those days; life is much easier now, with a reset button.

Despite the claims of longevity for early LEDs, I used to find they just didn't last very long. They are a lot better these days but heat can still affect them (built with a lot of plastic).

Ordinary filament bulbs are not officially available in UK any more.

I'm not sure what kind of lamp it is not the old type egg-like bulb, I think it isn't LED either because on the box of the replacement bulb there isn't any terms "LED"

 

[anorlunda]

I'd like to but our house is old, so using new kind of lamp wil

A modern LED bulb looks like the one in this picture. It should be compatible with your old sockets in the house.

 

[tech99]

One reason for failure of filanament bulbs at switch-on is the magnetic forces caused by the initially large surge current.

 

[Keith_McClary]

Light bulb is less popular today than it used to be so the motivation in production to keep or improve quality might have gone down.

The Phoebus cartel was an oligopoly that controlled the manufacture and sale of incandescent light bulbs. They appropriated market territories and lowered the useful life of such bulbs.

 

[nsaspook]

Most of the ON/OFF cold/hot cycle breakage I see from thicker heating Tungsten filaments is from stress induced fractures (mechanical stress as well as thermal stress). Small stress cracks form at a grain boundary increasing the localized resistance at those cracks. As the cracks grow from continued stress events the increased resistance results in a increasing voltage across each non-uniformity, more localized power dissipated at that point creating a hot(er) spots on the filament. Eventually one of the crack/hot spots will fail causing an growing arc that melts the ends of the broken filament. The classic signature of this premature breaking is the ball on the end of a still 'thick' filament. A properly worn filament should have two evenly tapered ends

https://www.researchgate.net/figure/Different-damage-types-observed-after-the-exposure-of-tungsten-to-thermal-shock-events_fig2_261294267

 

[anorlunda]

The Centennial Light bulb has been lit since 1901. Here's today's screen capture from the live web cam.

https://en.wikipedia.org/wiki/Centennial_Light

 

[sophiecentaur]

The Centennial Light bulb has been lit since 1901.

The history of lightbulbs is full of interesting stories. I found this in the Wiki "Filament Lightbulb" article:
"Some old, high-powered lamps used in theater, projection, searchlight, and lighthouse service with heavy, sturdy filaments contained loose tungsten powder within the envelope. From time to time, the operator would remove the bulb and shake it, allowing the tungsten powder to scrub off most of the tungsten that had condensed on the interior of the envelope, removing the blackening and brightening the lamp again."
I thought that would be worth sharing. A sort of manual equivalent to the halogen lamp.

 

[artis]

The Centennial Light bulb has been lit since 1901. Here's today's screen capture from the live web cam.

This bulb is so old and notorious that I believe the Mayan calendar and the Bible's Book of Revelation have references to it.I do wonder whether the bulb's longevity has to do with the rather low temperature of it's filament compared to more modern bulbs.

 

[sophiecentaur]

This bulb is so old and notorious that I believe the Mayan calendar and the Bible's Book of Revelation have references to it.I do wonder whether the bulb's longevity has to do with the rather low temperature of it's filament compared to more modern bulbs.

AFAIK, a red hot lamp would last for ever!
Would my recollection be right that the life is inversely proportional to the fifth power of the filament temperature? I'm sure I heard / read that somewhere in the past.
Certainly, there is a limit of 3695K (the melting point of Tungsten).

 

[anorlunda]

I do wonder whether the bulb's longevity has to do with the rather low temperature of it's filament compared to more modern bulbs.

It is well known that running an incandescent bulb at a lower than rated voltage greatly extends the life (and dims the glow).

There was also a report of Edison made DC bulbs displayed at the Menlo Park Edison Museum running for a century. But I was unable to find a source about their status today.