On Jan 2, 6:46*pm, Red Green wrote:
JIMMIE wrote in news:2e634943-f451-4731-b06f-
:

I just took apart a failed LED bulb replacement. The circuitry appears
fairly complex using caps diodes and active components Complex
relative to a circuit that is just a rectifier and current limiting
resistor. While the LEDs themselves may have high reliability I think
the failing point is going to be the power supply and I am not
expecting them to have much better reliability *than CFLs. I do think
there is a future for home LED lighting that will come when buildings
are wired for low voltage lighting that removes the 120 VAC to low
voltage DC power supplies from the bulbs.

Jimmie

Why did you take it apart? They are pricey and have lives rated at 10k-30k
hrs. All bulbs at this point should be under warranty. I could see the
curiousity angle if they were a couple of bucks.

The bulb was from work and they were nt going for the refund so it
just became curiosity to me. Processing the refund becomes more
expensive than the bulb. Not the first LED lights we had with this
problem. First we tried were for stairwell lighting. Two of the 3
failed within about 6 months. Failure analysis showed it was the power
supply. Since the stairwell was on its on breaker we opted to build a
LVDC power supply for the lights and bypass the existing power supply.
That was 3 years ago and there have been no more failures. I think LED
lighting as a direct replacement for existing lights is a big mistake
as the built in power supplies will always s be the weak link.


Jimmie