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 Post subject: LEDs still not mature?
PostPosted: Wed Nov 25, 2009 8:25 am 
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It may not be street lighting, but it is very relevant. Over the past few months Tesco in Havant near Portsmouth has been completely rebuilt, and on Monday next week it reopens. The keys were handed over to Tesco a few days ago so that they could start kitting it out with shelves and stock. The store is said to be relatively eco friendly and make use of environmentally friendly technologies. One of those technologies is LEDs backlighting the external "Tesco Extra" signs, rather than fluorescent tubes.

Bear in mind that Tesco was only given the keys to the store a few days ago. Last night I drove past the new store, and they were busy fitting it out. The "Tesco Extra" sign out the front was lit up, but already, after just a few days operation at most, the LED illumination was failing. The "E" in Tesco was not lit up at all. Meanwhile, the dashes that underlined "Tesco" were pulsating. Reminds me of my neighbour's LED floodlights. In one of those units half of the LEDs failed within two weeks of installation, and on another unit the LEDs developed a pulsating fault.

It goes to show that even in late 2009 LED technology is still failing.


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PostPosted: Wed Nov 25, 2009 5:56 pm 
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I bet Tesco bought the "value" version of the sign... ;)


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PostPosted: Wed Nov 25, 2009 9:30 pm 
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I wouldn't be suprised if they did, i have about 4 headlamps which contain 12 LED's about 4 in two of them are failing due to a poor power connection but on the brighter side i have two 3 LEDs per unit (3 LEDPU) cycle lights which are bright and these are hell of a lot better than the £3.99 each headlamps that i got.

I think it to do with the manufacturer of the LED's as you could have a decent factory producing 50 LED's out of the 50 maybe 20 might fail within 6 months of its useage so its a bit of a gamble really if it works or not.

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PostPosted: Thu Nov 26, 2009 1:12 am 
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I had 2 LED GU10 lamps burn out last year. These were the white ones from B&Q and not the coloured ones.


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PostPosted: Thu Nov 26, 2009 1:37 am 
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A recruitment agency in york city centre (opposite the goods entrance of M&S) called Manpower has LED stips on wallmount swan-necks illuminating the sign - one of the two strips has developed a fault whereby it blinks on and off at a similar frequency of a bus indicator.

Stelmer wrote:
I had 2 LED GU10 lamps burn out last year. These were the white ones from B&Q and not the coloured ones.

Hmmm, the LED lights I use to light up the pond area are all B&Q ones! :?
Well, I may not be using them for as long each day now, as I've been given an ultimatum to either take them down or fit a timer to them, otherwise the lights will be on the receiving end of a hammer...

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PostPosted: Thu Nov 26, 2009 10:32 pm 
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I think you should put them colour changing bulbs in them. They'd look miles better.


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PostPosted: Fri Nov 27, 2009 12:38 am 
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The colour changing LEDs look brilliant when next to water, they have something similar in Holmfirth which changes colour.

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PostPosted: Fri Nov 27, 2009 4:08 am 
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I was thinking of doing something with colour changing LED's, but more on the thought of a low level directional spot shining on the pond from the other side so that reflected wave lines shimmer on the wall of the cabin.

The thing is that single colour LED's are brighter than colour changing ones... a single colour one can be a 21 LED package (the ones I use in my bedroom), now the colour changers can also be 21 LED, but that's split between Red, Blue and Green - and whilst Red, Blue and Green are quite bright, when the lamps try to make other colours like White, purple, Orange etc they are dimmer.

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PostPosted: Wed Dec 23, 2009 8:54 am 
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I noticed a new LED installation last night when refuelling at Shell. Not only has the canopy signage had its fluorescent tubes replaced with strings of yellow and red LEDs, but the main under canopy metal halide lighting has been replaced with LED fittings. Previously, each canopy support pillar was surrounded by four lighting units, one on each of the four sides to each pillar, with the metal halide lamps either 150w or 250w. The new lighting only uses two lighting units surrounding the pillars, with the others blanked out, and the new lighting uses LEDs. I must say, the lighting is very bright, and I didn't notice the LED lighting at first. It was whilst I was looking up at the LED signage lighting that I noticed the main under canopy lighting was formed of lots of pin-points of light.

Certainly, down my way Shell is rolling out LED lighting, so keep an eye out.


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PostPosted: Wed Dec 23, 2009 5:10 pm 
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They weren't by any chance like these?  ;)

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If so, they are not just in Hampshire. I wonder what the round thing is on the fitting? 100 LEDS and as you say very bright. The Hi-bay fitting is sort of ideal for LEDS as you can get a large heatsink in the volume of the enclosure. The rest of the enclosure will be in in free air in the canopy roof void so can dissipate the heat.

Is this the beginning of the end for the "traditional" Lo/Hi-bay fitting? Come to think of it, the fitting is the same sort of size as a ZX3 or large Iridium/Sapphire. Petrol station forecourts are around 5m tall, could a modified fitting suffice at 8m?

I wonder how much power they consume? 100 LEDS say even if 1w each (and I suspect they are more than that) and say 50% efficient (which is not unreasonable for a LED)  would imply 200w so where is the power saving per fitting? There is only a saving if less luminaries are used, which wasn't the case for the ones I pictured.


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