Does It Hurt LED Bulbs To Turn Them On & Off ?

billt460

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I know fluorescents should not be turned on and off constantly. It's better to leave them on. But what about LED's? Is it better to turn them on and off as you leave the room... Or just leave them on throughout the course of the day?
 
The most likely failure point would be the LED driver circuit as opposed to the LED itself but that varies *wildly* between manufacturers. On average you should be good to flip them on and off as much as you want unless you have a lowest bidder brand/make.
 
I turn mine off if I'm leaving the room for more than 30-45 minutes. I'm more concerned with heat buildup than pulsing the power on and off. I'm using bulbs from reputable brands though. I suspect that some of the bottom-of-the-barrel brands wouldn't tolerate the on/off cycling as well though.
 
What is considered a "good" brand? And what is considered, "bottom of the barrel"? Are these things rated by Consumer Reports, or something like that?
 
I've had only good experiences with General Electric so far (specifically the "Bright Stik" LED9LS series). In six years or so I haven't had a single one fail even though I adhere nearly pathologically to the ethos of always switching off lights when I leave the vicinity.

There's also a great deal of praise for Philips and Feit Electric, but I don't have any personal experience with them and durability necessarily varies from model to model. "Bottom of the barrel" is usually what you'd see showing up unopened in pallet-quantities at thrift stores (NewLeaf and MaxLite come to mind).

I'm 95% sure CR has articles on this but I don't have a current subscription with them. This guy's youtube channel covers consumer LED bulbs in quite good detail (CRI, flicker, etc..): https://www.youtube.com/@TheHookUp Ultimately he recommends Philips Ultra Definition, but YMMV, of course.
 
Another vote for GE.
This is a company that really seems to know what they are doing.
 
As others have mentioned, heat is the enemy of LEDs more than anything else.

I've had bad luck with these GE Bright Stick lights... granted, all of mine are older, but even in hotels I've stayed in which use them, they have the tendency to dim dramatically over time. They haven't shifted color temperature noticeably, so I'm guessing it's a driver issue rather than LEDs themselves burning out in them. I did have issues with some of the original Cree bulbs having sections of LEDs burn out, but now they're stable.

I also saw TheHookUp's LED bulb review and bought some of the Philips bulbs he recommended. No qualms about them so far, but I've only had them for a year or so. We'll see how they perform over time. From the guy's tests, they seemed to have good thermal management/dissipation, so they should last a long time.

At one of my places I have a pile of Philips Hue bulbs I picked up on clearance and so far they've held up well with frequent use. Then again, for what Philips charges for these, they better!
 
I think it's generally better to switch the light off when not being used, especially if it runs hot (for any reason), but avoid too much on/off cycling. Ikea rates some bulbs by the number of on/off cycles (typically 25k) but not necessarily operating hours. Failure modes for incan. and fluorescent under similar conditions don't relate.

Many (most?) cheap recent A19 bulbs use linear regulation with LEDs in low-current high-voltage series configuration. Notable exception is Ikea's lowest cost bulb (under $1 each) 40W eq SOLHETTA which has a switching regulator based on 4-pin PT4558EN IC.

I do not know the dominant failure mode for specific components for on/off cycling versus continuous operation, would be interesting if someone has knowledge of this.

Dave
 
Properly designed led fixture should be able to run for years non stop with no heat issues, or be switched on and off hundreds of times a day, but of course with improperly designed, poorly constructed ones problem may be present anywhere, leds may overheat, driver circuit may overheat, spikes caused by on-off may case the light to fail. so the answer is, It depends,
 
If the Ikea bulb rated 25k cycles is cycled on/off every 1/2 hour for 3 hours per day, it should last 11.4 years. If turned on/off once, run also 3 hours per day, 11.4 years is about 12.5k hour run life; a bit low but seems reasonable for a bulb like this. Based on low power (3.3W) and efficacy of bulb (136 lumens/W), thermal cycling is probably not a big factor. It might be so for higher power bulbs which run hotter.

You might think the driver is most likely to fail, possibly, but LEDs are generating most of the heat, and thermal cycling could cause breaking bond wires, solder joints etc.

If "failure" is defined as L70 (reducing output by 30%), turning bulb off when not in use will be better.

Dave
 
As others have mentioned, heat is the enemy of LEDs more than anything else.


I've had bad luck with these GE Bright Stick lights... granted, all of mine are older, but even in hotels I've stayed in which use them, they have the tendency to dim dramatically over time. They haven't shifted color temperature noticeably, so I'm guessing it's a driver issue rather than LEDs themselves burning out in them. I did have issues with some of the original Cree bulbs having sections of LEDs burn out, but now they're stable.
Huh, I wonder if some of the difference is that hospitality establishments are more likely to run them closer to 24/7 and cook them in their own waste heat? It could be that my habits just mean that I keep them on a pretty gentle duty cycle. Lol, maybe I'll go Philips Ultra Definition after they finally bite it.
 
Huh, I wonder if some of the difference is that hospitality establishments are more likely to run them closer to 24/7 and cook them in their own waste heat? It could be that my habits just mean that I keep them on a pretty gentle duty cycle. Lol, maybe I'll go Philips Ultra Definition after they finally bite it.
I'm sure people leave the lights on continuously in a hotel than they would in their own home. My most recent encounter with a hotel using these had the GE bulbs in a desk lamp. It was a suite, so the desk and office area were completely separate from the sleeping and living quarters. I could see this lamp being left on all the time. By the time we got there it was down to about half brightness.

Something to remember is that inrush current on incandescent bulbs is a real bear. Until the tungsten filament heats up, it's darn near a dead short for a few milliseconds. You're also heating that metal up by some 2700 degrees in a matter of a second. It's rare for an incandescent bulb to blow after it's been on for awhile compared to when you first turn them on.

LEDs don't have the inrush current nor rapid heating issues that tungsten does.

Cheap drivers and poor thermal management are what kill most LED bulbs. Usually the driver circuits go long before the physical LEDs do.
 
I am sure "inrush" in LED bulbs is a much smaller issue in LED bulbs, if any. Many low-cost bulbs using linear regulator have a small electrolytic capacitor in the dc supply (4.7uF to 15uF typically) but also a series fusible resistor typically 5-22 ohms depending on the bulb.

Ironically most bulbs I've opened have been working. Two which had failed (including Philips) had one visibly scorched LED, unknown if the driver caused this or the LED itself.

Why Ikea rates some of their bulbs by on/off cycles is probably that number looks better than the hour runtime, for that bulb.

Dave
 
Does It Hurt LED Bulbs To Turn Them On & Off ?
Mostly no.

The simple answer is "not at all".

It hurts LED bulbs far less than it hurts incandescent or CFL (twisty) bulbs.

The longer more complicated answer is that it is possible it could hurt some designs of LED bulbs just a little bit, but probably not anywhere near the level that you would have to worry about it. When I say "hurt", I mean maybe they will not last their entire expected lifespans. Which probably will not be an issue anyway since most cheap LED bulbs don't seem to last their entire expected lifespans anyway. (They'll fail for some other reason first)

There are only two possible situations I'd possibly worry about this. One is if there's a small child who is constantly flicking on and off the light playing with it every day. (Even then, should still last longer than a year, and if it's a cheap bulb, you could easily just replace it) And the other is if it's somehow an extremely special irreplaceable, or extremely expensive rare LED bulb you do not want to take any risks with and you really want it to last for a decade or longer. (Like for example if we were talking about an L-Prize bulb or a Cree LED bulb, which are irreplaceable and hold a lot of collector value)

In any case, in general, an LED bulb is going to last longer if you turn it off when you are not using it, than if you just left it on all the time because you were afraid of turning it on and off.

Mostly this is probably not something you have to worry about. And I don't think any of the experts on this forum are even sure that constantly turning on and off an LED bulb does hurt it.
 
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