On 1/2/2015 6:56 AM, Arfa Daily wrote:
EE Times article that came to me by email today
http://www.electronics-eetimes.com/e...s_id=222923405
Arfa
I've never had a CFL failure that I could trace to the CFL.
It's always the electronics driving it. A power glitch can take
out a LED just as easily as a CFL.
Lifetime guarantee. If you can find where to send it and pay
more in shipping it back than the cost of replacement.
And it's not the lifetime of the light. It's the lifetime
of the supplier.
Home lamps are designed for cheap,cheap,cheap,
not for reliability. But it will get better over time.
I always giggle at flashlights that say you never replace the LED,
over 20,000 hour life, etc.
The elephant in the room is that in most cheap designs, they
put the LED directly across three batteries and hope the battery
resistance increases faster than the time it takes to melt the light.
And the better designs have a dozen high-stress parts in
some regulator.
I sawed a free harbor freight flashlight in half and soldered it
back together to make an extension. Put an 18650 in an extended light.
Really bright. Replacing three 1.5V with one 4.2V oughta work, right?
Not for long...but far longer than I expected. Put one ohm in series
and it looks like life might be ok. ;-) Still pretty bright.
There's a reason they ship with heavy duty batteries.
Home Depot has some really great deals if you watch closely.
I bought 44 40W LED's when they were 4 for $5.05 and replaced
most of my CFL. Turns out that two 40's in a Y-adapter was
way cheaper than a 60W and had better light dispersion.
Then they had 60W at 3 for $6.97 to replace 12 of the 40's.
Then they had 75W at ONE CENT. I bought all 8 of them to replace
some of the 60's.
There's no possible financial reason for doing that.
I tell myself that the LED's should last longer in applications
where you switch them on and off a lot. But I put LED's in fixtures
I haven't turned on in years. Don't judge me...I'm saving the planet...
In the attic, I have about a hundred used incandescents, right
next to the hundred CFL's, right next to all the spare LED's
I bought but never used.
Right next to the box of flashlights I couldn't help buying.
And I still mine Home Depot for LED deals. I need to go
to rehab for LED abuse.
Often we do stuff because we can, not because we should.
If I remember correctly, if you combine the MTBF of all the components,
the probability of system failure within the system MTBF is 37%.
Are we having fun yet?