I was at Best Buy tonight wandering aimlessly and noticed the refrigerator with the built in TV and other gimmicks, but I when opened one refrigerator (I think it was GE) and saw the array of LED's at the top I thought, "now that's a perfect application. never burn out and no heat."

Which reminds me, I have a bulb that has been burned out in my fridge for over a year. good thing there's two.

Especially since LED's do not like heat.

My company is doing a project for a major food producer where we are replacing 250 1000W MH fixtures with 300W LED fixtures in a 5 acre freezer at -30F. The reduction in heat from the MH's alone is calculated to pay for the changeover in about 3 years. The LED's in the 'fridge seem like a great idea along the same lines.

Good LED applications? Here's one we all see everyday:

Traffic lights.

Only disadvantages (and some cities won't use them because of this), is that they don't generate enough heat to melt the snow of the visors, and they don't last long in hotter climates.


Ian A.

For some jurisdictions these would be mission critical issues.

That can be easily fixed persay. a heating element. It does not to be hot, just warm. You may not get the energy savings but you would get the longivity which will reduce maintenance cycle which still saves money. I ought to copy write my post.

I don't know if this really qualifies as a good application or not, but it's something that I couldn't resist.

My wife and son came home one day last summer with slurpees and they bought these straws with clear plastic skulls, about the size of a walnut, near the tops. Inside the skulls were blue plastic brains. Pretty neat straws really. But I immediately thought about my son's broken fire truck sitting downstairs on my workbench...with two perfectly good LED emergency lights. So I remove the LED's, drill a hole through each eye in my straw-skull, insert LED's, and tape on two AA cells. I wired it all up and left a little piece of metal across the ends of the two cells...not quite touching so that if you push on it, it makes contact. When contact is made the LED's light up and my straw-skull has scary red demon eyes.

Maybe I'll grow up someday, but I doubt it.

When the final one goes, they carry appliance bulbs at Dollar Tree. You may have to replace them a little more frequently, but you can buy 4 for what the appliance shop/hardware store wants for them.

I like LED traffic lights, but they seem to fail quite often around here; patches of black or flickering. It's a moderate climate, so perhaps they are just being made poorly?

I can't wait for a practical solution for household LEDs; the household lamps you can buy with a hundred or so LEDs are way too expensive. The "real" white ones that have a combo of white and yellow LEDs to produce more "natural" light don't seem to blend together very well; some sort of fancy reflector/diffuser is in order. LEDs would solve the dimming problem that CFLs suffer from.

I am seeing more and more trucks on the road with LED tail and marker lights. A friend also has had them put on his enclosed trailer seem to work good for now.

There is a small section of Highway 403 between Hamilton and Brantford that has LEDs embedded in the ashphalt and used as lane markers! Believe me they work far better than those little reflective cat's eyes!
A.D

I have them on my bike, under the tour pack and saddle bags. Very eye catching at night and better than the factory tail lights.

we are in a Canada and go from -30ºC in the winter (with snow storms) to +30ºC in the summer and while driving I don't see any more problems with the LED bulbs than the Incandescent bulbs. I see more signals out of service longer as the city has cut back on the overtime to replace bulbs outside of normal working hours.

There is more of a problem with the old style of mechanical signal controllers freezing and locking out in the cold damp weather when the 60w bulb they use for an internal heater burns out.

gets to 45c here in summer, havent ever seen them changing out led traffic lights since they were installed! dont see any not working very often or at all anymore either! have a small light with 3 leds in it on my helmet at work, great for working in panels when lighting is bad, which is in lots of places at the power station around the boilers etc. Also was good when working in mining industry at night, trucks etc can see you easier once you are away from service vehicle.

How about the cordless tools that now have led lights in them? I work with an apprentice who has an 18V set and all the tools have led's. They're quite handy sometimes.

They are also great as pilot lights on control panels in substations and as indicator lights on overhead pole mounted contactors to show the on / off status.

Then of course as Christmas lights too. Hopefully no more faultfinding on awkward led strings.

Traffic lights ideal, the response time is a lot faster, also they are a lot brighter too.
Sometimes occasional led strings fail but the led cluster still works.
The problem with snow on lenses can be sorted with a heating element or small power resistor within the led housing.

That is the reason that most railway signals have the red lamp at the bottom. No snow build up in front of the lens.

LED's is going to be the next best thing since peanut butter and duct tape. I have used LED's for pilot light, I have a couple head lamps with LED's and Every project I am involve with that call for EXIT signs, they are LED's. They are everywhere up here. They are making leaps and bounds with LED's and some maufacuters are marketing task lighting that have LED bulbs. In a few years, we may be installing LED lights instead of fluoresent. Be careful though if you are thinking specing LED products. Know what you are buying and who you are getting it from. As the old sayig goes, if it is too good to be true, it is most likely is. Some of the LED products I have seen appear to be a little shady to me. Some of them seem to trying to make a quick buck.

A friend of mine used the LED christmas lights and made his local paper front page. The up front cost is high but they sure pay for themselves.

I have used LEDs for indicators in everything I have built since the Ford administration. That is about when IBM started replacing all the "360" lamps with LEDs.

I'm also doing a project for Vector. To upgrade OCB panel incandescent lamps with LED made assemblies.

These are 130 Volts filament lamps which are run at 120 Volts DC and give status indication of substation OCB's.
The lamps last normally about 2 months, and fail often earlier when a breaker trips a few times.
The lamps are B22 lamps.

I crush the lamp, clean out fitting and fit 2 series resistors and 3 or 5 LED's and a blocking diode.
A piece of 25 mm Ø conduit as outer housing.

The problem of lamps failing is now solved.
It takes me about 10 minutes per complete lamp assembly which will last now for a very long time.

The factory made LED lamps don't meet our requirements or are simply not available yet.

Dropping 120 volts or so through a resistor is pretty inefficient (half a watt or more). If you do it with a capacitor the LED will still light but it won't get hot.
You still need the diode or a R/G LED that glows yellow on AC

Most of the level (railroad) crossings on the Tarcoola-Darwin railway line have 12" LED lamps fitted. They are manufactured by Westinghouse.

gfretwell

These lamps run on 120 Volts DC so the Capacitor wouldn't work. hence the resistor option. ( loss in R's is about 1.2 Watts at 8 mA's)

I did trials with LED lamps on 230 Volts AC with a capacitor which had premature faillures of the LEDS.
Possible spikes on the mains had a different timeconstant and went straight through the Capacitor.
These were used as potential indicators on CT meters.
Also for this option a resistor was chosen. To dissipated one or two Watts in a resistor is better than having a 15 watt filament bulb lasting about 2 months.

Here is a site that has alot of LED lamps.
http://superbrightleds.com/
Rod

Dashboard lighting.

LEDs have been introduced on traffic lights here over the last couple of years ("here" for me meaning the city about 20 miles away -- I'm too far out in the sticks to have traffic lights nearby!). They really get your attention because of the quick "snap" from one light to another. As yet I haven't noticed any suffering from problems, although the climate here is much milder for both extremes of temperature than most parts of the U.S.

Some late-model cars here are using LED lights as well. The center-mount high-level brake light is the most common candidate for them, but I've seen a few using them for other lights as well. They seem to be hybrid arrangements though; I've followed at least a couple of vehicles with amber LED turn signals on the rear but still with conventional filament lamps for tail/brake lights.

Pauluk: Have you seen the new Range Rover out that uses the same set of "transparent" LED's for your normal red stop and tail lights but change to amber when the turn signal is activated? Looks really sharp IMHO !

A.D

No, I haven't seen that one, but if I'm interpreting your description correctly I don't think it would be allowable here under the British vehicle lighting regulations.

All vehicles manufactured for the U.K. since the mid 1960s have been required to have amber turn signals which are completely separate from the red brake lights. This is a problem that those of us with North American vehicles with combination red brake/turn signals often face come inspection time. It's a matter of finding a good inspector who will "bend" the rules a little for an import! (Some British 1950s/early 1960s cars also used combined red brake/turn lights on the rear.)

I thought the amber turn signal lights came from Japan and I assumed it was just because they didn't figure out how US manufacturers did the combo thing. It sure made wiring trailer lights harder.

Off topic, but it is too bad people dont know how to use turn signals.

Hmm Maybe these were some aftermarket thing that I saw but I am sure I have seen them more than once on a couple newer Range Rovers I have seen over here. That or its a North American thing for the 'Rover
Off topic a bit. Most North American vehicles I see now are going to separate lamps for turn signals and brake lights. Weather they are " red and red" or "amber and red" they are separate lamps.

Norcal: Turn signals must be the same as the posted speed limit is around here " JUST A SUGGESTION" LOL

A.D

Dashboard lighting. - Yes they are great from the anticipated reliabilty point of view, but don't make the mistake I did.
I bought a Blue led conversion kit for my old Volvo, because dismantling the panel is a *** job. Thought they should last for ever; very fashionable, blue, too.
No-one mentioned that you can't see a red pointer in a blue light when the background is black!
At least I'm getting quicker at dismantling it.

Hey if you use your turn signal they will know what you are going to do and cut you off.

BTW worse are the people who always have a turn signal on

The only Australian made car that had red stop/turn/tail lights was for memory the 1956 FE Holden, the light lenses were red and clear in the tail light assembly. When it became mandatory for the turn signals to be amber in colour, people either found the next models indicator lens (the FC model-produced in 1958) would fit where the reversing (clear) lens was in the lamp assembly or aftermarket indicator lights (usually round) were fitted under the original light so the vehicle still had reversing lights with clear lenses.

The same problem existed with Ford F series tail lights also (on the 1973-1977 models) where the lenses were red & clear on the US models with red & amber on the Australian trucks.

The lenses were the same size so swapping them over was a five minute, two screw job.

I think you'll find that most parts of the world outside the Americas now require separate amber turn signals front and rear. They're the norm right across Europe as well as the U.K. now.



It could be, although the aftermarket thing sounds a distinct possibility. Manufacturers often have to adjust external lighting to suit local laws. All new cars here from 1980 onward were required to have a rear fog light, for example.



Are you saying that Australian law required all existing signals to be changed to amber, as well as requiring them on new cars?

We had a mixture of arrangements when turn signals started to become standard equipment on British cars in the 1950s. Some models went straight for separate amber signals, while others adopted the approach which was standard in the U.S. of using the existing brake lights as rear signals and putting a twin-filament bulb on the front to serve as a combination white parking/turn light.

Some models used a combination of the two methods. A lot of the Hillmans from the early 1960s had separate amber signals on the rear but combination white signals on the front. When the regulations demanded amber all round from 1965 they could no longer use combined lights on the front, because the rules still required front parking lights to be white (they became amber in the U.S. of course).

Going even further off topic, but the other signals which were employed here on some cars in the 1950s were little semaphore arms, pivoted and recessed into the B-pillars. Switching on the signal caused a solenoid to extend the arm on the appropriate side and light a small amber lamp on the end of it which could be seen both forward and rearward.

Back to LEDs though, and one other application which I don't think has been mentioned yet is modeling. There's the obvious application of red/amber/green LEDs for model railroad signals, but the yellow types and some of the new white types are also quite useful for things like interior car and building illumination.