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Visit the Bulb

This is probably the only Bulb with it's own website. We talked about this awhile back and I check back on it periodically. This is the 'Famous Livermore Centennial Bulb' it has been burning more or less continuously in Livermore, Ca. for the last 100+ years! (since 1901) - Talk about Long-Lasting!

This is a frame from their Bulb-cam which is updated every 30 seconds. (Refresh browser) Any time of day if you want to check on it you can come look at it. (Or some may want to watch it continuously? ) Use it as a nitelight?..

You can visit 'its' website for more info at: http://www.centennialbulb.org/

Sign the guestbook, 'it' likes when you do that.


Bill

During the daytime you can see the filament itself.

This reminds me of a situation I had recently where Outside Lighting was installed around a circular driveway. There was 12 fixtures (rated 60W or 100W) that were lamped with 40W Bug-Lites and the bulbs kept burning out - like some would be lost every day or every other day. The line was a dedicated 15A circuit, GFCI protected, UF cable down 12"+ and voltage was within normal levels. After several bulb replacements We finally tried 40W 130v 'Rough Service' Bulbs and the problem went away. Any Ideas?

BTW, the owner wanted these yellow Bug-Lite Bulbs in the worst way, so that was the only type that was tried prior to the 130v ones.

Bill

Bill
My guess is that the operating voltage is lower than the normal voltage of the 130v rough service lamp. Back when I got into design, there were a few places where the old RLM incandescent fixtures were specified, and all with 130 volt filaments. I was told they would last longer. Since I am not into maintenence, I don't know if they did or not.
Just a thought.

Warren,

Yes, I think they are more 'sturdy' too, probably due to a slightly thicker filament.
I was wondering if anyone had any thoughts about the premature burnout of the standard bulbs. It was highly unusual. One thought I had was that their street was off a main drag and probably got some truck traffic. Some of the fixtures were 100' away from the road though, but that's my best guess on that one.

BTW,

I was told that ABC has been doing a lot of filming out there and 'The Bulb' will be on Peter Jennings, abc news, 5:30 (their time) this evening (Thurs). If anyone gets a chance they should tune in!


Bill

filament and 0 vaccum...is key to long lasting bulb

I think this Bulb just had another Birthday.
(101 !!) I check on it once in awhile.

OK, it's my nitelight (kidding)
If you go to the site there is more info on the history here and they have a guestbook for comments.
http://www.centennialbulb.org/

Bill

I think you could make any standard lamp last 100 years if you were to lower the voltage considerably and prevent vibration.

Ed

Ed,

I was told by them that it is standard voltage and it did not even have any surge protection on it until recent years.

Bill

Please correct me if I'm wrong, but I though light bulbs had an inert gas inside of them, not a vacuum. A true vacuum would be about 15 lbs per square inch of pressure on the outside of the bulb and would crush it, would it not?

I thought they had nitrogen in them or something...

I've written to Kilokat7 ( www.BulbCollector.com ) to see if He will join us again to tell us what he knows about these old Bulbs. If you have some time you should take a look around his site. There are some interesting pictures of old-time things like this Bulb:



and Alarm Clock:



(There's some British stuff there too Paul)

Bill


[This message has been edited by Bill Addiss (edited 07-13-2002).]

Fascinating -- I can spend hours trawling through this sort of stuff!

These bayonet-cap lampholders look like the fitting which is still standard for most of our smaller bulbs in England:



For those of us who are radio enthusiasts, Tim's site also has a good assortment of early vacuum tubes ("valves" in British terminology).

electrical nostalgia...interesting stuff.

but will they last in a crawl space...

I have a cheap ceiling fixture that burns out bulbs very quickly too. In my case the problem seems to be heat - the fixture has zero ventilation. When using two 60 watt bulbs (within it's specs) they burn out in a few days or weeks. Since switching to 40 watt bulbs the bulb life seems about normal, and I worry less about burning the house down.

.... still running ....


Bill

Just for grins...
I'd like to learn how this bulb compares to modern bulbs in terms of lumens, efficiency, color temp., etc. Anyone know?

John,
It is only 4 watts ! That pretty much explains the longevity.

At the turn of the century (not this) there was extensive research into light bulbs, just like there is today in computers. A range of materials were used and there was competition to offer the longest bulb life. This meant that bulbs with 10,000 hour life were sold.

There are 8760 hours in a year, which means that this bulb has been on for more than 876,000 hours. That is close to a million hours!!!

Small aside — At one time, the corrugated sleeves for GE extended-service incandescent lamps advised against their use unless the cost of replacement was very high {1300-foot broadcast tower} or the cost of energy was very low {restroom in a 60-year-old hydro generating plant.}

.... still running ....

Bill

That must be a perennial bulb.

I seen some technical information from G E that showed live verses output of incadesent bulbs for various percentages of voltage above and below design voltages. It is amazing how much the life changes. I attended a church where a weekly job for the pastor was replacing burned out exit light bulbs. Several a week. I replaced all the 7 watt 120 volt ones with 11 watt 130 volt bulbs and the failure rate went down to a couple a year.

Still running.

Hope you don't mind Bill.

Roger

Thanks Roger!

We've been 'watching' this Bulb for almost 5 years ourselves now!

Time flies, doesn't it?


Bill

The carbon filaments for bulbs were made from strips of carbonised bamboo.

Ah so, grasshopper, many Hans make light work!

Bill,
It certainly does.

Roger

Great thread Bill.

Good it got bumped up.

Never read this one yet at ECN.

I'm aware of the fireststion lamp, amazing 100 years of service.

I'm into meters a lot and about 15 of my in house lamps have hour meters on them.

Most lamps last around 800 hours out of the claimed 1000 hrs.
Some so called long life lamps are actually rated for 250 Volts! while our nominal voltage is 230 - 235 V.
These appear to go for around 2300 hrs.
Certainly the voltage is critical for the life of the lamp, overvoltage is fatal undervoltage even 10 or 15 volts makes the bulbs last a lot longer although with less light output.


My outside lights which are on all night via a timeclock last around 8000 hrs with standard lightbulbs. These have a 1 N 5408 diode in series in the fitting to halfwave the voltage. and from the control point a 200 watt lamp in series to smooth in inrush peak. replacement around every 2 years, sometimes longer. the 3 bulbs used are 40 watts each.
Vibration is not good for filament lamps as are enclosed fittings where excess heat will cause early faillure.

Then the inrush current at switch on is hard on the filament too. most lamps tend to fail at switch on with the usual "ping"

I guess the US 110 or 130 Volt lamps last a lot longer due to the thicker filaments ?
or they are claimed to last 1000 hrs too ??

I got some of the CFL's too which have done 12349 hrs out of the claimed 15000 hrs. These are still going strong.

'Inrush current' isn't be a serious problem for filaments until they get degraded with use. All lamp filaments lose material at the high temperatures of service- it migrates off the filament as metal or carbon vapor and can often be seen on an old bulb near the base, where the glass is coolest. Inert Gas filling reduces the migration of material, [as does use of a thicker wire of course]. 'Vacuum' bulbs are obsolete simply because gas filled ones last longer.

The 'inrush' "problem" is supposed to be worse with metal filaments, as resistance increases with temperature = high amps at start. The speed of the temperature rise in a modern bulb is such that this resistive effect is of little consequence, and there is negligable temperature overshoot. Failure may also be due to minute dislocations or faults growing in the filament material with each cycle of on/off, a function of material quality,
[ie 'They last longer if you leave them on'].
Tungstan wire is drawn from powder-metallurgy formed slugs- the material is never melted, so the wire is a 'welded' material. Carbon filaments were grown by a plant and so suffer from biological variability. Interestingly, carbon filaments had a negative resistance curve, the resistance falling with temperature rise. They still failed eventually - often by blacking out the glass surface with so much soot that the light couldn't get out!
The '100 year' carbon bulb is running at a very low filament temperature. This has slowed migration to a negligable level, but eventually.....

Alan

side note, sorry for straying, I think this is really cool. Personally, I like that old fashoned orange glow. I have tons of little 11 watt exit sign bulbs in lamps all throughout my house. I was at a furniture store once that had these neat bulbs in all of their lamps for sale. They are kinda hard to describe, but, it almost looked like they had 2 filaments. They intersected in an almost heart shaped pattern, and glowed that orange like color. The woman running the store didn't know where they had gotten them, and I didn't feel like buying a $200.00 lamp just to get a bulb. Am I crazy or has anyone else ever seen anything like this? An "Edison" bulb of sorts. Any info appreciated.


They had a party for the bulb when it had a milestone birthday. I bet 1,000,000 hours (roughly) would be a neat excuse to have a big town party. I know that I am definately going to be sad when/if this ever burns out. It's a neat landmark to have. The worlds oldest lightbulb. kinda cool

>>Am I crazy or has anyone else ever seen anything like this? An "Edison" bulb of sorts. Any info appreciated.

Soundtech, these are available as Carbon Filament bulbs, check out: http://www.rejuvenation.com/fixshowMRB2/templates/selection.phtml

and
http://www.rejuvenation.com/typepageLight%20Bulbs/templates/houseparts_group.html
(Scroll mid page down)

Only $14/bulb!, and they use 40W to give off 10W of light. Probably not the best for housewide lighting, unless you have cheap power!
mike

Hey those are cool, neat find.

Thanks for the bulb web site. that is great.

Thanks!

The fact that incandescent bulbs last longer at lower voltages is why I turn down the dashboard illumination on my cars.

Those bulbs are somewhat of a pain to replace if they blow

Newer cars use LEDs so I suppose it doesn't matter as much anymore.