questions on lifespans...

[orionlion82]

we have LED stoplights and LED brakelights and LED turn signals.
they are even thinking of putting them on the new boeing jet.

LED's dim alot over time.
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who is to say they do not dim below the required brightness as laid out in state and federal law?

the NEW led stoplights are BLINDING.
the older ones are less bright than the halogens that are left.

do they test this stuff for brightness or has anyone figured out the problem yet?

what happens when the stoplights get so dim you cant see them?

 

[R33E8]

Then you replace them.. They probably still cost less in energy and replacement cost..

The lifetime could be helped if they manufacturers spent more time with cooling and design...

 

[orionlion82]

Then you replace them.. They probably still cost less in energy and replacement cost..

The lifetime could be helped if they manufacturers spent more time with cooling and design...

HANG ON now...

theres a falshood in the assumption that most people understand how LED's degrade over time.

how often do you see your street/public utility department out measuring the lights and comparing the results to charts?

granted they COULD have a "best guess" lifespan and just replace them on a schedule to remain withing the legal standards...

but this is government we are talking about.

agian with the LED taillights.
sure they are blinding now -
but in 2 years - 3 years will they still meet standards?

(FMVSS108)

 

[Oznog]

What? Lightbulbs stop working suddenly in thousands of hours.

LEDs, with proper conservative thermal design, 100k hrs for the dimming to become significant, or 11 years. If you want them to last even longer put in more and run them at slightly lower power.

 

[TigerhawkT3]

HANG ON now...

theres a falshood in the assumption that most people understand how LED's degrade over time.

how often do you see your street/public utility department out measuring the lights and comparing the results to charts?

granted they COULD have a "best guess" lifespan and just replace them on a schedule to remain withing the legal standards...

but this is government we are talking about.

agian with the LED taillights.
sure they are blinding now -
but in 2 years - 3 years will they still meet standards?

(FMVSS108)

There's a falsehood in the assumption that a semiconductor device is responsible for making "most people" or "the street/public utility department" or lighting manufacturers lazy and/or ignorant. Improper design or maintenance is in no way the LEDs' fault.

 

[orionlion82]

What? Lightbulbs stop working suddenly in thousands of hours.

LEDs, with proper conservative thermal design, 100k hrs for the dimming to become significant, or 11 years. If you want them to last even longer put in more and run them at slightly lower power.

another false premise.

fmvss 108 lists the minimum candlepower of nearly every light you have on a car.

LED's behave differently.
who checks it?
the state inspection guy that only cares if they light up and your tires are inflated and the horn works for a charge of $65...

same for stoplights.
im sure there are brightness standards on those things too.


YES i would assume they all have some built in tolerance - but
in the real world how do you recon if any of those lights are at the minimum or not?

 

[StarHalo]

Find a dead LED in your house.

 

[TigerhawkT3]

another false premise.

fmvss 108 lists the minimum candlepower of nearly every light you have on a car.

LED's behave differently.
who checks it?
the state inspection guy that only cares if they light up and your tires are inflated and the horn works for a charge of $65...

same for stoplights.
im sure there are brightness standards on those things too.


YES i would assume they all have some built in tolerance - but
in the real world how do you recon if any of those lights are at the minimum or not?

Um, what's false about what Oznog posted? Incan bulbs do indeed suddenly stop working after a few thousand hours. LEDs can indeed last ridiculously long with proper fixture design. Running them at lower power can indeed increase their lifespan.

 

[rushnrockt]

I am a bit confused what the issue is here. My car's headlights have deteriorated over time to the point of being useless even at high beam. So if we are to follow the logic, who checks that?

Is regular maintenance and checking the condition of important parts no longer a part of proper upkeep?

 

[orionlion82]

I am a bit confused what the issue is here. My car's headlights have deteriorated over time to the point of being useless even at high beam. So if we are to follow the logic, who checks that?

Is regular maintenance and checking the condition of important parts no longer a part of proper upkeep?

as to stoplights - i wonder.

as for cars, - my buddy works in a haundai place.
not a mechanic, but in keeps an ear out.

unless the cars stop dead on the road people only change the oil.

even better there was an engineer who tracked and recorded his tire pressures.

the thing came in with 8 pounds in the tires and a neatly written logbook tracking the declines in pressure over 6 months. the engineer "oiled" his valvestems to keep the brass fittings shiny.

the oil ate up the rubber valvestems they sell him new ones every 6 months.

all he ever asks is "whats haundias problem with the valvestems" :thinking: