Philips LED light bulb is comically flattened

Lightbulbs do have all the air let out tho :slight_smile:

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Yeah - most LEDs are marketed as “Dimmable” but what they should say is “Dimmable under certain circumstances”.

We have Lutron dimmers but they’re definitely old. LED’s strobe and sometimes even flicker when dimmed. I have to replace them but I’ve also read that it’s possible that it might not even be just the dimmer but the wiring itself could be wrong for LEDs. My understanding of electrical systems is pretty poor though so I didn’t really fully get it. I have to crack the books.

Anyone else heard of home wiring that could be LED incompatible? Or is it really just replacing the dimmer?

The recommendation of the Cree bulb from Home Depot is a good one. When in doubt, refer to thesweethome. They do this work for you! Note their review specifically looks for bulbs that can handle the dimmer.

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You want the Cree bulbs sold at Home Depot

Just be sure to pay with cash.

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Heh, just saw this in the review too, regarding the Philips (which is the “runner-up” in their analysis): “The only flaw with the Philips SlimStyle is its comparably subpar dimming performance.”

I recently replaced the bulbs above my bathroom mirror with GE LED bulbs. This one specifically:

Not cheap, but I’m very pleased with the results.

I also put one into an Ikea tracklight hanging pendant lamp on a dimmer. It only strobes at the lowest settings. From about 30% on up it’s solid.

Do you know if this is what is currently being used in automotive taillights? If so it’s still entirely jarring to my neurons. Granted, it’s a heck of a lot better than frequencies cycling below 85 Hz or so.

Part of it is persistence as well, I’m sure. A CRT at 85 Hz with phosphorescence is going to be a lot mellower than an LED at a higher frequency.

LEDs plus ceramic heater bulb used in vivariums. More importantly, how the hell are you gonna smoke meth with one of those things?

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Modern CFL bulbs use newer technology and flicker at 10,000 hertz or more.

(Since the late '80s.)

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All old-school incandescent and halogen in my house. We use lower wattages and dimmers, and shut them off when we leave the room. Glowing analog filaments are warm visually and thermally; digital lights are cold and dead, and make me grumpy.

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I still shell out for GE reveal. I find the color to be more… something. I have these Philips bulbs in my garage and a few other places and the blinding white light is grating.

This. I replaced my bulbs with CFLs in the early 2000 (when I got my own place), and plan to replace them with LEDs when they burn out. Thus far I have not had any burn out yet so I’m still using CFLs everywhere. Probably the only time long life is an annoyance factor in light bulbs.

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I’ll second (third? fourth?) the recommendation for Cree.

They’ve always been very good, and now they are also quite affordable.

I don’t think that’s the case. I have a dimmable LED in my house with an LED compatible dimmer and it totally flickers. My understanding is that LEDs are either on or off and they are only “dimmable” by strobing them so that they are only on some percentage of the time, thus looking less bright.

I just bought one of these exact “flattened” bulbs last week for a ceiling fan – this was the cheapest bulb at the store – and the glass globe doesn’t fit over it. But then I saw on the packaging, it’s not supposed to ever be in a fully enclosed fixture. So now it lights the basement stairs (ridiculously bright) and the old CFL we had down there is in the computer room (yellow and dim). Gonna have to replace it.

So I appreciate all the recommendations for Cree bulbs.

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Try the Cree bulbs. The color will make you happy.

I just had my first CFL go out, now the problem has been choosing a new LED bulb, I expect them to be so long lasting that it feels like a major commitment and don’t want to get it wrong :blush:

Its been two months now and the dining room light is still out! (Its partially lit by the kitchen and living room lights so I’ve made due. Anyway, from the responses on this posts looks like I’m getting a CREE! :smile:

To everyone who keeps saying LEDs are only dimmable via PWM, no they can be dimmed via reduced current as well. Since everyone seems to like Cree here is the pdf of the XP-E white LED chip:

http://www.cree.com/~/media/Files/Cree/LED%20Components%20and%20Modules/XLamp/Data%20and%20Binning/XLampXPEHEW.pdf

In there is a set of graphs showing relative luminous flux vs. forward current. At 350ma it is making roughly 100 lumen. That doubles to 200 lumen at roughly 800ma or falls to 50 lumen at 165ma. The main reasons PWM is so wide spread is the fact it’s cheap. There are driver units that work via current control, but most pre-built ones start around $20. Obviously scales of economy and all that, but a PWM setup can be built into a single chip that can do everything from rectify the line AC to DC, step it down, and give you rough control over the brightness. In all honestly a $.10 capacitor would probably help smooth out the ripple enough to make it tolerable.

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They’re also the cheapest I’ve seen for their quality. I think the IKEA LEDs are cheaper, but they’re pretty lousy.

Most commonly sold LEDs and CFLs use a variable duty cycle (PWM) driver to produce different brightnesses, though specialized applications can use CCR (constant current reduction) if dimmer linearity and color consistency are not a priority. If you’re using a good quality LED/CFL compatible dimmer (Lutron C*L or Leviton Universal), and are using dimmer-compatible LED bulbs and are still getting noticeable flicker, check the following:

  • Improper circuit grounding.
  • Excessive circuit load. Most common in old houses where fuse panels have been converted to breakers and single circuits supply many outlets/lighting fixtures.
  • Noisy neighbors. Poorly isolated loads and/or severe RFI can generate noise on the line and disrupt PWM drivers. You might need to install dimmers that are rated for increased RFI filtering (Lutron Maestro, for instance)