LED corn lamps

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GoldDigger

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Not me. What's a corn lamp?
Individual LEDs on the outside of a cylinder, like kernels of corn on a cob. They tend to have a fairly narrow intensity pattern radiating out from the "cob", so the results will depend on the geometry of the luminaire and its reflector.
 

A/A Fuel GTX

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WI & AZ
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Electrician
I've got some 100W HPS street light type fixtures that I was thinking of converting to LED's. I figured I'd remove the ballast, put 120V to the lampholder and screw in an LED. The only thing is, I wish they made LED's in a softer color as neutral white is the softest I can find so far. Sounds like the OP is doing the same thing.........
 

TNBaer

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Location
Oregon

A/A Fuel GTX

Senior Member
Location
WI & AZ
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Electrician
Not a real great solution but to each his own, I s'pose.

Sensity probably makes the best one on the market: http://www.sensity.com/product-portfolio/led-post-top-retrofit-600-series

Vivid will do these in 27k: http://www.vividleds.us/pages/led-lamps.html

And Beacon makes a great Acorn retrofit as well: http://www.beaconproducts.com/products/lrk3d or: http://www.beaconproducts.com/products/lrk2v

This is hardly my favorite thing to do though. Too many what-ifs for my liking.

Just curious, would you just stay with the HPS until the LED retro's are perfected or do just not like LED's period?
 

TNBaer

Senior Member
Location
Oregon
Just curious, would you just stay with the HPS until the LED retro's are perfected or do just not like LED's period?

I don't dislike LEDs. Given, there's a lot of bad product out there. A LOT. Much of it isn't even better than IR Halogen and little of it is better than linear fluorescent. But in outdoor lighting it makes sense.

So I don't like these "corn lamps" because you don't really see anyone reputable making them. Take a company like "Light Efficient Design" which makes these "corn lamps." How do they determine whether or the luminaire can regulate the heat properly? They can't, so they stick a fan inside their lamp. What do fans do? Attract dust. What gets inside outdoor luminaires? Bug parts. The whole thing is asking for disaster. Here we are telling people their new leds will last 10 years by purchasing products from companies no one has heard of and likely won't be around for three years. Everyone in the industry knows this is asking for trouble. Maybe it comes by premature failure, or maybe a hefty lumen maintenance issue.

The other thing is outdoor luminaires have different distribution patterns, reflectors that may or may not work with different LED sources.

I design a lot of these projects. A LOT. And I usually get around these cheaper components by redesigning outdoor layouts with great product by companies that have been around the block a time or two. Make no mistake, I readily pursue these projects daily and specify LED regularly for outdoor but rarely do I use retrofits. Too many "what-ifs" and promises by people I don't know.
 

A/A Fuel GTX

Senior Member
Location
WI & AZ
Occupation
Electrician
I don't dislike LEDs. Given, there's a lot of bad product out there. A LOT. Much of it isn't even better than IR Halogen and little of it is better than linear fluorescent. But in outdoor lighting it makes sense.

So I don't like these "corn lamps" because you don't really see anyone reputable making them. Take a company like "Light Efficient Design" which makes these "corn lamps." How do they determine whether or the luminaire can regulate the heat properly? They can't, so they stick a fan inside their lamp. What do fans do? Attract dust. What gets inside outdoor luminaires? Bug parts. The whole thing is asking for disaster. Here we are telling people their new leds will last 10 years by purchasing products from companies no one has heard of and likely won't be around for three years. Everyone in the industry knows this is asking for trouble. Maybe it comes by premature failure, or maybe a hefty lumen maintenance issue.

The other thing is outdoor luminaires have different distribution patterns, reflectors that may or may not work with different LED sources.

I design a lot of these projects. A LOT. And I usually get around these cheaper components by redesigning outdoor layouts with great product by companies that have been around the block a time or two. Make no mistake, I readily pursue these projects daily and specify LED regularly for outdoor but rarely do I use retrofits. Too many "what-ifs" and promises by people I don't know.

What's your opinion on the LED's made by CREE?
 

TNBaer

Senior Member
Location
Oregon
What's your opinion on the LED's made by CREE?

I don't have any problem with their product. Their LEDs are far from the industry leader at this point in the game. I'm seeing a lot of the Philips Rebel and Nichia chips, the former being very versatile and the latter being high lumen and long life (over 1,000,000 hours TM21 test). Cree's business model is starting to catch up with them in the OEM market.
 
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