Every industry has it's own jargon—words and phrases that most people outside that world would have a hard time understanding. So when our apartment's maintenance crew sees us carrying a box of 100-watt incandescent light bulbs (we're hoarding for the phase-out) and tells us to "be careful about overlamping," we immediately turn to one place: Google.
What is "Overlamping"?
It's when a light fixture is fitted with a light bulb that has a too-high wattage. Every fixture has a wattage rating that is recommended by the manufacturer.
Is it Dangerous?
For sure. Putting a 100-watt bulb in a 60-watt fixture could cause intense heat, melting the light socket and the insulation on the fixture's wires.
Any time you have that kind of damage on wires, you're at a big risk for arc faults, where an electrical current falls off its intended path— a leading cause of home fires.
Even after you pull the offending bulb out, you could still have lasting damage to your fixture.
How Can I Avoid It?
More modern fixtures should disclose their wattage rating—just don't go above that with your bulbs and you'll be safe. If your fixture is older, and without a wattage recommendation, go the safe route and use 60-watt bulbs (or lower).
(Images: Flickr member Deiru licensed for use under Creative Commons, Flickr member ntr23 licensed for use under Creative Commons)
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Good Article. Any idea on why my chandelier always blow out one bulb when I fill them all up. When I leave a dead one in, no more bulbs die. But when I replace it, one will die out pretty quickly.
Yes, the same thing happened with my antique chandelier. This is a perfect example of "overlamping." The electrician came and took a look and told me to use 15w utility bulbs. The lamp can only handle 100w, and there are 5 prongs. So I had put in 25w chandelier bulbs, and one of them always blew out. The light would then work fine with the remaining four 25w bulbs (100w total), but 125w was too much for it. So funstraw I would suggest trying a lower total wattage. Mine works fine on 75w total.
PS you could also try mixing it up, and put in half 25w, half 15w (if you've got 5 prongs like me, that would get you to 95w). This site sells 15w chandelier bulbs if you don't like the industrial look of utility bulbs (I rather do, they're sort of edison-like). http://www.1000bulbs.com/category/frost-straight-tip-candelabra-base-decorative-chandelier-light-bulbs/
Why on earth are you hoarding incandescents? They burn more energy and CFL's last seven times longer. Also, since the wattage tehy use is so low compared to the light they emit, you never have to fret about "overlamping" in the first place.
I live in WV, where the rationale for blowing the tops off mountains, and filling in the streambeds with the rubble is that "we have to do that to meet the demand for electricity". Somehow, these complaints about CFLs just don't resonate with me.
* The light from CFLs can be dimmer than incandescents.
* Incandescent light is warmer.
* Some CFLs don't come on at full strength right away.
* CFLs don't work as efficiently with dimmer switches.
* CFLs are harder to properly dispose of, thanks to their tiny mercury content.
So many of us talk "green" until it involves some personal inconvenience, and then we rationalize our choice. So go ahead and hoard your incandescent lightbulbs and worry about "overlamping"--I'd rather have the mountaintops back, myself.
I try to use CFLs most of the times but their light is so cold. I use an incandescent bulb for reading, for example. I can't stand CFL's light for some things.
By LED bulbs. All problems are fixed. Great lamps, only a bit expensive. But I am sure people here are more concerned about the environment then the initial price of a lamp.
I have a few things that call for 60W bulbs. Is it okay to put "100W" CFD bulbs in because they run at less than 60W. Less heat generated but more light.
What are people's thoughts?
@Jwink, yes it's fine. The actually wattage is what's important, not the light output equivalency. I have a hanging fixture with a 250 watt equivalent cfl which runs on 42 watts.
Also, people, if you're unsatisfied with the color temperature of your cfl, buy a warmer one. You're probably looking for something in the range of 3,000K, but you can get even lower. The higher you go, the colder it gets.
Try different kinds of CFLs. I hate the ones that are everywhere, but we got some "soft white" ones from the hardware store, and the light seems a lot like incandescents. A very nice find.
For those who have this odd hatred for incandescent lighting - the new [oh so wonderful - so I'm told] cfls contain MERCURY!
So thank you ever so much for destroying the water supply of future generations.
A misconception: The minimal mercury in CFLs is less than the mercury spewed by the 4x power using incandescents. And you should recycle the CFL, so hopefully the mercury will be safely disposed of.
MJ, if your lamp is rated 100 and it blows bulbs at 125, you have a problem (the safety factor is usually way above 25% and bulbs do not burn out if it's exceeded); get a more knowledgeable electrician.
"spewed" by the power plant, that is