Lighting issue: Premature light bulb failure

[dan]

I posted a message earlier about light bulbs in my kitchen failing prematurely (lasting roughly 1 month). I received some good suggestions but did not find anything. Since then, I have paid particular attention to the lights (there are two on the same switch). When I turn them on, I have noticed a slight delay for the second bulb to light up. Could this be the issue? I would think both would instantaneously light up at the same time. I have not checked the connections, but will do so this weekend.

[RickH]

I assume you switched bulb brands a few times to determine it's not just a batch of bad bulbs. If you switch the two bulbs, does the delay problem follow the same bulb? Are they ceiling cans? If so, the thermal switch might be causing a delay due to carboned contacts. Need more info. Temperature change is the hardist thing on a bulb, thats why bulbs dont last long outdoors, especially in winter. Slow start dimmers can extend bulb life a little.

[Tony Hwang]

Hi, Make sure all connections are tight in the fixtures. Ever checked voltages? Also you can get so called long life bulbs(commercial grade) at the lighting store which usually has a bit higher voltage rating. My house came with these bulbs when built in '94. More than 90% of this bulbs are still working. Another thing is heat. Excess heat will shorten bulb life.

[Jeff Wisnia]

Rick, can you offer a cite confirming that temperature change is the hardest thing on a bulb.

I'd think that given the huge difference between ambient temperatures and the bulb filament's white hot operating temperature less than a hundred degree swing in its starting temperature wouldn't mean diddly.

Do automobile light bulbs fail more frequently in Minnesota than in California? I think not.

Did you maybe mean to say that it's the outside weather conditions which cause bulb failures, stemming from moisture induced corrosion of sockets and bulb bases, which can cause all sorts of bulb failures?

Jeff

[borne]

I thought "commerical grade" was cheap junk that contractors put it when building a house?

[Tony Hwang]

Hmm, Temperature is critical on some situations. Some bulbs work with cooling fan. Fire hazard and keeping the bulb under normal working condtion.(temp) Try an experiment, One bulb running hotter than it should and one under normal running temp. Hotter one will get dark sooner and it'll burn out quicker. Anything exposed to harsh environment won't last long. That's why there is such thing as mil-spec., commercial grade, consumer grade, etc,, etc. Do you think car headlamps are built with same spec. as a bulb in the kitchen? I won't install a bulb from HD on a space shuttle, LOL!

[Tony Hwang]

Hi, What kinda contractor? Fly by night scammers or professionals who know what they are doing? Tony EE(ret), class of '60

[RickH]

By temperature change I mean sudden temp change, the sudden in rush current to a cold filament going hot causes it to flex and eventually break. Slow start dimmers bring the filament to temperature slowly and avoid some of the sudden flex and resulting metal fatigue. For a cite I would have to google around, but google for how slow start dimmers help bulb life and that will probably explain more, I read it myself years ago. My outdoor bulbs never lasted long, so I started using CFL's outdoors in the carriage lights.

[Jeff Wisnia]

Thanks, the inrush current part I agree with. I mistakenly thought you were referring to outdoor ambient temperature changes as contrasted with the generally smaller range of indoor temperature changes.

Ans did I. The lights on either side of our front door had three candelabra based flame shaped bulbs in each of them when we bought the place. I don't think we could go for more than a month without one of those six bulbs burning out, and it required a stepladder and some serious arm twisting to replace a bulb, usually accompanied by my cussing when I dropped one of the little decorative nuts which held the tops on those fixtures.

Shortly after CFs became available I replaced the three sockets in each of those fixtures with a single edison base one and stuck in CFs. That was probably close to ten years ago now ant the original CFs are still going strone here in Red Sox Nation.

***********

I've seen "bulb life extenders" for incandescents which were just NTC (negative temperature coefficient) thermistors housed in a housing you could stick into a socket before screwing the bulb in.

Don Klipstein's work describes that application thusly:

Jeff

[Clark]

Dan, I don't know if this helps you but, I had a fixture that was going through bulbs like yours is, my tenant was putting 75 watt and 100 watt bulbs in a 60 watt fixture (it was pretty burnt up) I replaced the fixture and put in the right watted bulb and my problem went away, go figure..

Clark

[Joseph Meehan]

First, let's get some information. What kind of lamps are these? Standard tungsten, reflectors, florescent??? It makes a difference.

Generally high voltage, poor air circulation, poor connections over wattage lamps for the fixtures and vibration are big causes of short life.

[Telstra]

Power saver bulbs not only use 80% less power for the same light output but last for up to eight years

[RickH]

You could replay that same parch scenario here. I'm in White Sox nation, BTW thank you for Carlton Fisk, he gave us many great years here.

[willshak]

One of the complaints against using CFLs is that they are slow to start. The extender would cause the same complaints for an incandescent as a CFL, but using more energy than a CFL.

[Clark]

But also contain mercury that should not go into landfills.

Clark

[terry]

Yup: And repeating myself for the umpteenth time;

A check with our local municipality advised that CFLs are (like the longer fluorescent tubes etc.) "Hazardous Waste" and trash collectors can refuse to take them! Although most people will probably just chuck the occasional one in with the regular waste and they will go unnoticed!

I guess that's a few more poisoned fish in our lakes and oceans? The drainage from our biggest dump in this part of North America, often a horrible orange stream, drains right into the Atlantic Ocean!

But hey; it's along with all those human discarded part used DDT, 24D (Agent Orange) and anti-dandelion and other herbicide/insecticide chemicals.

[terry]

One brand package here says that an equivalent to 65 watt CFL bulb uses 15 watts.

15/65 = 0.23 or 23% so the 'saving' is 100 - 23 = 77%, pretty close to 80% as stated.

But, in this moderate climate, that 'wasted' heat would contribute to heating the house, in place of the electric heat cutting in! Lighting is mainly used in the evenings and at night, especially as the cooler evenings 'draw in' (shorten). Which is when it is cooler and heating is required.

So still haven't convinced our selves there is any savings yet. from using a $2 to $3 CFL in place of a 25 cent incandescent that uses four times the amount of electricity when it is on. Our one experiment with a 'cheapy' CFL outside, which tends to be on all night, over the front door, during the winter was not a success! It looks like a more expensive CFL is required for temps. below freezing? May try one when the existing 5000 hour long life bulb which has been there for the last five years or so burns out.

[RickH]

I dont see any hazardous material warnings at the Home Depot lighting aisle, nor prominant on the packaging that I can remember. Maybe the package tells you it's hazardous if it pops, but that is in the "small print".

[Jeff Wisnia]

The "extenders" I've see just slow the start by a second or two, no where near as long as the CFLs in my outside front door lights take to come up when it's cold outside.

But you are correct on the energy usage.

I can't wait for LED bulbs to get down to a reasonable price. From what I've read they'll last nearly forever and won't be a serious hazardous waste. LEDs seem to have already "taken over" in many of of the traffic signals around here.

Jeff

[willshak]

If it pops, and all that mercury flows out, just think of the horror! All those moths crashing to the ground.