bulbs burning out prematurely

[apjames]

i do alot of lighting maintenance for retail stores, and ive come across a couple places where they say this. never ballasted bulbs, always 120v par38s or par30s etc. in track heads or recessed fixtures. its always throughout the entire store, multiple circuits, different kinds of fixtures. store im at now has about 90 bulbs out, they said store was near fully lit couple of months ago. i always verify good voltage randomly throughout, check panel for loose connections (mainly nuetrals), verify proper bulbs/wattage is being used and i never find anything. anybody have any idea what else might cause this?

 

[Dennis Alwon]

Change to 130v bulbs. It will make a world of a difference. Voltages are usually over 120V thru the poco so that higher voltages puts a strain on the 120v bulbs.

 

[GerryB]

130 volt bulbs are a great idea. Could there be any unusual vibration from anywhere? I had a HO whose kids jumped around a lot on the second floor and the BR30's went out quick.

 

[jeremysterling]

Yesterday, I was at a retail store where the managers told me the exact same thing. She said when she relamped a PAR30 75W track head, the other three heads on the track all burned out simultaneously. She had around thirty burned out storewide.

I'm skeptical of the claim that these lamps last only a few months. I think the managers let time slip them by and the T8's from the last maintenance call from two years ago are all mostly burning, but most of the incandescent has burned out.

 

[cadpoint]

There is lamp life to consider here. Par 30 is only floating around 2500 hours. So at say 16 hours for 156 days, almost seems about average; minus the bad connects and self heat...

 

[jim dungar]

I'm skeptical of the claim that these lamps last only a few months. I think the managers let time slip them by ....

Once, I told a retail shop to to use a 'Sharpie" to write down the date of the lamp relamping, on the back of the bulb. they never complained about 'early' failure again. Of course being on for 16 hours a day, can reach the normal life expectancy relatively fast.

 

[Electric-Light]

For a range of voltage near the rated voltage, each 5% increase in voltage halves the life of incandescent life.
Other compounding factors include vibration from doors slamming and floor vibration from people walking above it.

A dimmer set on maximum setting will increase the lamp life as even at full setting, its not quite 100% the line voltage. If the voltage is substantially higher, preset type dimmer set to a notch below maximum setting will be a better setting.

 

[PetrosA]

I'd definitely agree with the 130V recommendation. If that's not an option or too expensive (local suppliers around here are between $12-$18 per compliant PAR 30 lamp), upsell them to LEDs. With the cost of compliant halogen PAR lamps nowadays, upgrading to LEDs just for the energy savings can be a pretty easy sell for stores.

 

[Electric-Light]

I'd definitely agree with the 130V recommendation. If that's not an option or too expensive (local suppliers around here are between $12-$18 per compliant PAR 30 lamp), upsell them to LEDs. With the cost of compliant halogen PAR lamps nowadays, upgrading to LEDs just for the energy savings can be a pretty easy sell for stores.

So, that they walk the talk.. or you can have fun providing free labor on warranty replacements.
Sold to them installed and give 'em a tale of almost forever life, it better come with parts & labor for many many years.

 

[PetrosA]

So, that they walk the talk.. or you can have fun providing free labor on warranty replacements.
Sold to them installed and give 'em a tale of almost forever life, it better come with parts & labor for many many years.

I'm not sure I follow you completely, but I wouldn't sell the long life bit myself. Electronics aren't all that

 

[G._S._Ohm]

Rough service bulbs have additional filament support as an anti-vibration measure.

Q: Given that you have 'a vibration environment', do rough service last longer than 130V, in hrs/$?

There are formulas for incand. lamp life vs. voltage but I've never seen any for shock/vibration magnitude/freqs/duration vs. lamp life.

And are there rough service 130v bulbs?

With the labor cost of relamping, the bulb cost may relatively small.

 

[dhalleron]

I just looked at a house for this reason. The tenant claimed bulbs burned out fast and she lost a couple coffee pots and a microwave oven over the past 3 years.

I found nothing loose in the outlets or panel. Voltages were good. Even had the power company come out to take a look. They changed the connectors on the service entrance but didn't find anything.

The incandescent bulbs this lady was using were 120 volt. Her branch circuits were running right at 126 volts. I told her to try 130 volt bulbs.

Not sure about the coffee pots or microwave. Maybe they were due to die anyway. Or maybe the power company did have a loose neutral or something.

 

[G._S._Ohm]

I just looked at a house for this reason. The tenant claimed bulbs burned out fast and she lost a couple coffee pots and a microwave oven over the past 3 years.

The incandescent bulbs this lady was using were 120 volt. Her branch circuits were running right at 126 volts.

That's a pretty short MTBF.

(120/126)^15 = 48% of rated life.
(130/126)^15 = 1.6x the rated life.

If some lamp manufacturer posts the standard deviation of lamp life then informed HOs with several of these bulbs could actually tell if they're getting screwed.

And 'typical' lamp life is not the mathematically rigorous 'mean' or 'average.' Not using weasel words is bad for business.

 

[PetrosA]

With 126V you definitely want 130V lamps. Back in the 80s we had that issue in the town where I worked and the supply house "normally" sold 130V lamps. You could get 120V, but you had to ask for it - the problem was that bad.

I don't think they make a rough service PAR lamp but you can certainly get 130V PAR lamps, at least from Philips. They cost a few dollars more per lamp than 120V though. I get 130V rough service A lamps for everyday use. Again, they cost more, but they're still available and they last a looooong time with most voltages - they're just not as bright.

 

[Electric-Light]

I'm not sure I follow you completely, but I wouldn't sell the long life bit myself. Electronics aren't all that

I'm saying that if you're going to pull the "super long life, 50,000 hour" to talk customers into chalk up absurd amounts of $$$$ for "LED technology" you haven't done your walk without offering super long parts & labor warranty to go with it.

 

[Speshulk]

One day some kid is gonna stumble across this thread and laugh about the "old timers" talking about those old school incandescent bulbs.

 

[PetrosA]

I'm saying that if you're going to pull the "super long life, 50,000 hour" to talk customers into chalk up absurd amounts of $$$$ for "LED technology" you haven't done your walk without offering super long parts & labor warranty to go with it.

I wasn't going to pull that talk with them. My point was that now that traditional halogen PAR lamps are out, and the new IR or whatever flavor is almost (and even more absurdly) double in price, selling a customer a reasonably priced LED equivalent which happens to offer huge savings in operating costs is becoming an easy sell. Even in residential I'm seeing a shift based on pricing - a year ago I would have recommended 5" cans and 50PAR30 lamps. Now that they are nearly $20 per lamp, I have started selling 4" recessed and 7W PAR20 LEDs. At 15% of the electricity used, payback is fast, the customer feels good and green and it becomes a no-brainer.

 

[kwired]

As others have mentioned a lamp rated for only 2000-5000 hours is going to reach that many hours rather quickly if it runs all day every day.

Aside from that something I have run into a lot over the years is lampholders that have had the lamps overtightened when installed. This is especially true with sockets with an aluminum screw shell. Overtightening stretches the shell and pulls it loose from the (usually a rivet) connection to the supply conductor. This becomes a hot spot in the socket and shortens lamp life.

 

[Electric-Light]

As others have mentioned a lamp rated for only 2000-5000 hours is going to reach that many hours rather quickly if it runs all day every day.

Not they won't

Time adds up the same way. No quicker/less quicker

 

[jmellc]

I have occasionally had issues & found bad splices in can lights or loose fitting sockets, where the center pin would not make good contact. I gently bend the pin back up with a pen or small screwdriver. Of course, that only lasts so long. An extra quarter on higher quality sockets would eliminate some of that. Even expensive lights often have very cheap sockets, with brittle plastic shells & cheap metal threads.

I haven't noticed but are 130V bulbs available in all varieties? That is a good thought. I see voltages pretty regularly up to 124, 125 & 127. As low as 112 sometimes, but more over than under.

I also see a fair number of bulbs with cheap metal bases that are rough finish, making them harder to screw in & out. I try to keep some "bulb grease" that I get in foil packs from Auto Zone. Especially on candelabra bulbs, it helps keep them from breaking off in the sockets.