In LED Lighting, Retro Isn't Cool
Solid State Lighting Design LED Lighting News - Editorials/Commentaries
Author: Tom Griffiths - Publisher
March 20, 2008... The fun part of the job is cheerleading for the solid state lighting and LED
industries. The hard part is when we need to shine a spotlight on a current
industry shortcoming that isn't simply fixed by the next step in efficiency,
or the next improvement in costs. Even harder is when a player that knows better
lets a poorly conceived, engineered or manufactured product get onto the consumer
shelves. The Christmas lights we raved about in December have failed to live
up to their promise. Hey heroes... leaders... suck it up and do the whole job
right before we repeat the mistakes that the CFL industry has already made.
So here's the set up. Two 60-light blue strings were procured in mid-December
and tacked over part of the front of our single-story ranch-style house to see
how they would do. About 80 days later, half of one of the strings is dead.
Ever the LED champion, I assigned likely blame to a local squirrel's teeth,
but reserved the possibility that one of the drivers tanked up. I know LEDs
themselves shouldn't simply fail, and if they do, it is extremely rare, especially
when you're talking about a running time of less than 2000 hours, and a duty
cycle of less than 50% (as suggested by the cool strobe effect when the light
string is shaken). Yesterday, a quick visual ruled out the squirrel, so recognizing
the opportunity for an investigation into the weak link in the design chain,
I grabbed an empty kitty litter container to stand on, and dragged the faulty
light set down to see what we could learn.
That's when things went retro on me. Generally, I like "retro" stuff.
1970s American muscle cars reborn in the 2000s with familiar style, more power,
a real suspension and better fuel economy. 1960s toasters (the real thing, or
modern replicas) that work quickly and announce their task complete by gracefully
tossing browned bread into the air. In the instance where the toast gets jammed,
the exposed heating wires inside threaten certain death as a reward for misplacing
the knife you're sticking in there to free your breakfast. CD burners that look
like vintage tube radios are on that list too (for the cool part, not the certain
death part). The kind of retro none of us likes is the kind that rolls back
progress, and that's exactly what I found as I popped out each of the 30 LED
"bulbs" on the dead part of the string and plugged them into the working
part to figure out what had fried.
That's when it got really interesting, as I discovered several of the LEDs
to be mounted in their plastic retainer at angles that were other than straight.
"It adds some of the old hand-assembled character," I thought, as
waves of nostalgia swept over me, remembering a time when the annual tree trimming
tradition consisted of methodically plugging in last year's light string, then
wiggling each bulb to see if we were lucky enough just to have a loose bulb
to explain why something that went into the storage box working came out of
it 11 months later not working. Nostalgia turned to mild annoyance as I discovered
that the LEDs at each end of the section were in a differently sized holder
than the 28 in the middle. The annoyance elevated another notch when it turned
out that they weren't just differently sized, but also keyed in different orientations
depending upon which end of which segment you're on. The next surprise came
as I found that some of the connecting wires inside the holder were corroded
(good old brown rust, to be specific). Horrors... I dared left the light string
mounted along the roof edge get exposed to liquid precipitation? Lucky I hadn't
strayed past the product warning tag limit that classes them as "temporary
decorative use only" for a maximum of 90 days. Explosion and death may
have been imminent.
As the testing proceeded, we came to the real shocker; not one, but two of
the LED bulbs were dead. They did not have corroded connectors and were seemingly
randomly dispersed in the string, with one near the middle of the section, and
one towards an end, although not at the end. I suspect someone reading this
from a "big, brand name" supplier is chuckling thinking that this
will have taught me a lesson about buying cheap, non-branded light strings.
I thought of that, actually. In fact, I thought of it in December when I recognized
the opportunity that presented itself in a long term test, and decided we needed
to return the non-brand name versions and instead pay a little more for the
ones from two of the biggest names in lighting. We tried them both, and settled
on the ones with a sleeker design (I won't be more specific than that, or those
in the know will probably be able to discern the exact brand). Just to make
sure the dead-LED blame was placed correctly, I then transplanted all the working
LEDs back into the dead section of the string to verify it was working and that
just the LEDs had died. The section was fine. It was now mostly my unwavering
faith that had died (or at least taken a hit).
So there I sat, staring at inconsistently-sized holders, corroded connectors
and two dead LEDs, realizing that even one was sufficient to knock out half
the string. At least 20 years ago, about any string that could be found had
"stay lit" technology that allowed a dead filament or broken bulb
without shutting down the string. It also became apparent that while the connector
was keyed, there wasn't anything to prevent the consumer from removing an LED
from the holder, and swapping it into another (something that would seem to
come in handy if you discovered on of the odd sized section end holders had
a dead LED). I reversed one in the middle of the string, and much to my surprise,
the string lit, although that LED didn't. Nor, apparently, will it ever light
again. In the interest of science, I treated its neighbor to a similar experience.
Once restored to the correct orientation, it still lights, but only dimly. I
can't honestly say that I'm not expecting a fire... At least we only paid a
noticeable premium for the LED string, not an outrageous one. Understand as
well that the LED's death may not have been the LED's fault, it is a system
issue, but there is no excusing the manufacturer when it comes to a product
that can be rightly expected to be leading the way as far as consumer impression
regarding the use of LEDs in all types of lighting applications.
The guy who was so confident that Christmas lights had hit their niche that
he had even tossed out the boxes and warranties wasn't so confident any more.
To add to the concerns, as I mentioned this upcoming commentary to someone in
the lighting service industry yesterday, they laughed and said, "Which
color box was it? I recommended LED Christmas lights to a lot of friends and
then found myself acting as the customer service department as I kept getting
call after call about how the things were dying on them. There were even cities
that made a big deal about going all 'green' with their LED Christmas lights
and then got to watch the strings them tank up left and right." Another
friend commented that they'd purchased a string of white lights, and the color
was simply wrong.
Two major name brands, one was unattractively constructed, the other one bit
the dust in less time than any of our "left them installed and running
for awhile" incandescent strings ever have. Speaking to those brands as
a consumer, I have to ask, "What were you possibly thinking? Do you take
us for freakin' idiots?" To make the message to all of us in the SSL and
LED industries as clear as possible: The leaders better get it right now
or this effort will be set back for years. Specifiers, designers and consumers
will look towards the leading brands as their benchmark that the technology
can be trusted. If your company is an up-and-comer, you'll be best served
by cheering the leaders on towards setting an uncompromising standard of quality
and functionality, or your up-and-coming will likely take longer than your cash
reserves will let you wait. We already have plenty of choice when it comes to
short-lived, poorly thought-out lighting options. Let's not go retro on this.