Lightbulb wattage

[noparlpf]

How do you tell what wattage bulbs a light fixture can handle if it's not actually printed anywhere on the fixture? The old bulbs are also the cheap kind where the print burns off after a while, so that's not helpful. I think one of them says 60 but it's not super legible so I'm not positive. I know you shouldn't put a bulb with a higher wattage in because it tries to draw more current than the fixture can handle, but I don't know what to do when the fixture doesn't tell you what it's designed for. It's your typical-looking kitchen fixture with three sockets and a fan. Should I just go out and buy some 40W bulbs in case this isn't supposed to take 60W or 70W bulbs?

[factotum]

Where on earth are you still buying bulbs that require 60W? Modern CFL and LED bulbs use way less than that, even if they're technically "60W equivalent".

[Gnoman]

Generally, the rating on light fixtures isn't about power draw, but waste heat - a 60 Watt bulb will get hot enough to melt hard plastic (such as that used to make LEGO bricks, as I discovered in a youthful indiscretion) and ignite easily flammable substances (as I discovered when I found smoking paper towels thrown into a light fixture at work). Both problems can be solved if you use LED bulbs instead. Even 100-watt equivalent LED bulbs don't draw enough power to be a problem, although there is a potential issue with the size of them.

[noparlpf]

Where on earth are you still buying bulbs that require 60W? Modern CFL and LED bulbs use way less than that, even if they're technically "60W equivalent".

Don't ask me, the previous tenant left a couple of old-school 60W incandescents and slightly-less-old-school 72W 100W-equivalent incandescents in the closet.

I took the covers off the other two sockets and one of the sockets says "Max 13W CFL T3." Do they actually make sockets designed to not take incandescents now? Is it bad that I (well, the previous tenant) had some old-school incandescents in there?

[Gnoman]

The amount of heat generated by the bulb can matter, but only really at higher wattages, and the physical size of the socket (or the bulb itself if you have a cover over it) obviously is important, but the type of bulb only matters in a few situations, generally those involving dimmers or three-way fixtures (the sort that you can set to low/medium/high brightness if you put the appropriate bulb in, not the sort of installation were you have multiple switches that can turn the light on or off). Most likely the manufacturer just replaced "Max 60 Watt type A bulb" with the CFL equivalent.

[veti]

I took the covers off the other two sockets and one of the sockets says "Max 13W CFL T3." Do they actually make sockets designed to not take incandescents now? Is it bad that I (well, the previous tenant) had some old-school incandescents in there?

I don't know, but that does sound bad.

If some cheapskate builder or half-assed DIYer has put in fittings that are only designed to handle the heat of a 13W CFL bulb, then a 60W incandescent will (at best, if you're lucky) melt the fixture. At worst, it could burn down your whole house.

That, to me, seems like a sufficiently severe downside to justify erring on the side of caution. Particularly as the added cost of doing so is only a few dollars.

[Peelee]

Can sockets take compact fluorescent and not incandescent? I thought the sockets and bases were pretty well standardized (well, apart from size differences, which are also standardized), and incandescent, CFL, and LED all use the same bases and fit in the same sockets. Is this changing?

[Gnoman]

No. The entire point of the CFL bulb was to create a drop-in replacement for incandescents. The CFL bulb itself is on the way out thanks to increasingly-cheap LED bulbs for the same sockets (which don't have any of CFL's downsides), so there's no reason to try creating a specialized socket for them. It is remotely possible that somebody decided to go ultra-cheap on a fixture and only spec it to handle the heat of a CFL, but this is very unlikely.

[factotum]

It is remotely possible that somebody decided to go ultra-cheap on a fixture and only spec it to handle the heat of a CFL, but this is very unlikely.

I'd disagree with that last part--the difference in heat generation between, say, a 60W incandescent and a 12W CFL is large enough that you could make some real savings in not having to handle that level of heat in your light fitting or, more particularly, your lamp shade.

I think it'll be a little while yet before LEDs supplant CFLs, personally. They may be better for the environment thanks to not containing toxic mercury, but they're still a lot more expensive than CFLs for a similar brightness of bulb, and I don't think it's even possible to get LED equivalents for the brightest CFLs.

[Gnoman]

For lamp shades, I can see putting such a low limit, but for the fixture itself going that low would make for a rather flimsy assembly.

As for LED vs CFL, right now a 100 watt equivalent (the brightest anyone's likely to need) runs about 2.5 Times as much for LED, with the benefits of having even lower power consumption, near invulnerabilty, little health hazard if you do management to break it, the ability to work in any orientation (CFL bulbs are notorious for acting up if you run them sideways or upside down), and being completely silent. The only real disadvantage is that the higher powered ones tend to be a little too large.

[Lord Torath]

I think it'll be a little while yet before LEDs supplant CFLs, personally. They may be better for the environment thanks to not containing toxic mercury, but they're still a lot more expensive than CFLs for a similar brightness of bulb, and I don't think it's even possible to get LED equivalents for the brightest CFLs.G.E. has already announced (http://www.nytimes.com/2016/02/02/business/energy-environment/ge-to-phase-out-cfl-light-bulbs.html?_r=0) that they are phasing out CFL production. They might be gone sooner than you think.

[AMX]

As for LED vs CFL, right now a 100 watt equivalent (the brightest anyone's likely to need) runs about 2.5 Times as much for LED, with the benefits of having even lower power consumption, near invulnerabilty, little health hazard if you do management to break it, the ability to work in any orientation (CFL bulbs are notorious for acting up if you run them sideways or upside down), and being completely silent. The only real disadvantage is that the higher powered ones tend to be a little too large.

FWIW, I've had bad experiences with cheap LED bulbs - IIUC the fixture I have doesn't offer enough ventilation, causing the bulb's PSU to overheat and die. They actually failed faster than the incandescent bulbs I had before.

I have not encountered that problem with higher-quality LED bulbs, but it's something to keep in mind if you have to decide between CFLs and discount-brand LEDs.

[Dodom]

When I moved, the last tenant had left a lamp with three bulbs. One had the original 40W, and the other two had been replaced by 60W bulbs, and had a large hole melted into the plastic above the bulb. Not even in contact with it, it melted from the convection heat alone.

[Alent]

G.E. has already announced (http://www.nytimes.com/2016/02/02/business/energy-environment/ge-to-phase-out-cfl-light-bulbs.html?_r=0) that they are phasing out CFL production. They might be gone sooner than you think.

Good riddance to those headache causing abominations. :smallbiggrin:


FWIW, I've had bad experiences with cheap LED bulbs - IIUC the fixture I have doesn't offer enough ventilation, causing the bulb's PSU to overheat and die. They actually failed faster than the incandescent bulbs I had before.

I have not encountered that problem with higher-quality LED bulbs, but it's something to keep in mind if you have to decide between CFLs and discount-brand LEDs.

They really need to make a new light socket for LED Bulbs and remove the LED Drivers from the bulbs themselves so they aren't exposed to as much heat. It would increase the cost of sockets, but considerably reduce the cost of LED bulbs, and we'd actually get the lifespan we're supposed to get from them instead of paying 2x our energy savings in new LED Bulbs because the cheap chinese LED Drivers release their green smoke too easily.

Pity that none of them are as easy on the eyes as straight incandescent bulbs. :smallfrown: The most incandescent like LED bulb I've found for that is probably the most easily green smoked set of electronics I've ever seen. :smallfurious:

[Peelee]

Pity that none of them are as easy on the eyes as straight incandescent bulbs.

Speak for yourself. Daylight CFL/LED bulbs look so much better than anything else, and it's not even close. I am aware I am in the minority on this opinion.

[noparlpf]

I generally don't like CFLs as much as incandescents, but I feel like the soft white LEDs are pretty good. They have a broader light spectrum than CFLs and pretty close to an incandescent, so it feels a little more "natural."


I don't know, but that does sound bad.

If some cheapskate builder or half-assed DIYer has put in fittings that are only designed to handle the heat of a 13W CFL bulb, then a 60W incandescent will (at best, if you're lucky) melt the fixture. At worst, it could burn down your whole house.

That, to me, seems like a sufficiently severe downside to justify erring on the side of caution. Particularly as the added cost of doing so is only a few dollars.

I mean, I've been here over two months and nothing burned down so I'm guessing it's an actual 60W socket and they just have the equivalent CFL rating on it instead for some weird reason.

When an LED bulb is rated as "100W equivalent" does that mean it's in terms of lumen output or heat output, then? If it's just light output, then since LEDs produce so much less heat for the same light output, is it safe to use a higher-watt-equivalent LED? Or is it a bad idea anyway because the bulb's controller circuitry is more sensitive?

[factotum]

Any bulb listed as "XXX watt equivalent" means the bulb is as bright as a regular incandescent of the specified wattage, whether the bulb is halogen, CFL or LED. An LED would need to be about 15W to produce that much light, which would require a big bulb with large heat sinks in it, I would think--probably much larger than the incandescent one would be, so it might not physically fit in the space available.

[Gnoman]

When an LED bulb is rated as "100W equivalent" does that mean it's in terms of lumen output or heat output, then? If it's just light output, then since LEDs produce so much less heat for the same light output, is it safe to use a higher-watt-equivalent LED? Or is it a bad idea anyway because the bulb's controller circuitry is more sensitive?

Light output. Most people aren't accustomed to thinking in lumens and benchmark a light source based on the wattage of an incandescent, because that is what we are used to. A 100 Watt-equivalent LED is identical to a 100 Watt incandescent except for physical size and power draw. Because the power draw is so dramatically reduced, you can indeed use an LED bulb in a fixture designed for a much dimmer incandescent, provided that it fits. A 100 watt-equivalent draws as much power as an 11 watt incandescent, so you can use just about any LED bulb that physically fits.

[keybounce]

I generally don't like CFLs as much as incandescents, but I feel like the soft white LEDs are pretty good. They have a broader light spectrum than CFLs and pretty close to an incandescent, so it feels a little more "natural."

I'm sorry, but "soft white" should never have been allowed to call itself "white". It is yellow.

Optical types can argue about the specific a* and b* numbers, but the bottom line: daylight bubs are "white", and yes I know that means greenish-yellow white, and those other bulbs are sunrise/sunset color, just to different amounts.

-- Someone with SADS who actually needs real artificial daylight

... did I just say "real artificial"? Where's my Ovalquick?

[Peelee]

I'm sorry, but "soft white" should never have been allowed to call itself "white". It is yellow.

https://media.giphy.com/media/1Z02vuppxP1Pa/200w.gif

[factotum]

Odd, I've just put a "soft white" LED in my upstairs room and the light appears to me to be whiter and brighter than the CFL that was in there before.

[Alent]

Odd, I've just put a "soft white" LED in my upstairs room and the light appears to me to be whiter and brighter than the CFL that was in there before.

The brain has an amazing ability to do its own white balancing. For some people it does a better job than others. Brighter light also does a good job of faking the brain out, too.

The real test is to take a digital camera outside, white balance against daylight on a white sheet of paper, then come in after the sun goes down and photograph that same piece of paper and compare. "soft white" almost always changes the color in some way.

[noparlpf]

A better test is to use an actual spectrometer. Soft white LEDs are mostly white, apparently. The blue LED covers that end pretty well, and the yellow phosphor covers green, yellow, and red pretty well. There's a bit of a dip in the blues between blue and green, a bit of a dip in the higher wavelength reds, and not much violet, but it's a pretty good spectrum of wavelengths. I feel like it's closer to daylight than white incandescents or CFLs. But yeah, the majority of the light from the phosphor is yellow-orange.

Incandescents are arguably less "white" though because the light they emit is mostly red-orange with very little blue or violet. But I guess we like warmer color temperatures, which is why a lot of people prefer that. CFLs have discontinuous spikes of different wavelengths, which is probably why they usually look bad.