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LED external lighting

LED external lighting

LED external lighting

(OP)
A question for the North American guys who do lighting design -

We're using LED luminaires to replace our external lighting across a large industrial complex as the aging HPS fittings reach the end of their useful life. I've received a quotation from one of our suppliers offering a near-equivalent alternative luminaire from Cree as well as the type we are currently using. I know Cree have a good reputation as a semiconductor manufacturer, but I don't know them as an end product manufacturer and have no experience of their luminaires.

I'm interested because we have a good luminaire from a well-known British manufacturer which we are adopting as a site standard, but the Cree offering has come in significantly lower in cost. Optically the Cree alternative isn't quite as good as the British design - slightly lower output, and poorer light distribution - but given the cost differential it is good enough for our application. I generally believe that you get what you pay for, but in the LED lighting market that rule doesn't hold true: there's a lot of expensive crap out there and also some well-priced quality products if you can find them. I'm just not sure where Cree are on that cost / performance / reliability range because they're almost unheard of in the UK lighting market.

Any experiences or comments would be welcome.

RE: LED external lighting

I have an ongoing discussion with LightLab (Warning - do not believe a word of what they are telling you) and Cree is the "as it should be" reference in almost all respects. I cannot say in what respect it is'nt. But there must be one or two.

I haven't used their stuff. So I can't say that I have any practical experience. But they don't seem to have disappointed anyone, so far.

Gunnar Englund
www.gke.org
--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.

RE: LED external lighting

I can't speak as to their luminaire-level packaging (i.e., COTS), having never seens it in any detail, but their reference designs for luminaire engineering in general are pretty top notch. They understand the heat dissipation side of things and provide appropriate heatsink designs, and the electronic drivers are also top notch. With all of that said, I would trust what they create without much worry.

Dan - Owner
http://www.Hi-TecDesigns.com

RE: LED external lighting

My kitchen used to be illuminated by 7 x dual 40 watt bare fixtures above translucent panels in a suspended ceiling.
The panels got nasty looking over the decades as cockroaches died on the top surface and left stains behind, and eventually all of the ballasts died.

We replaced them with four LED 2'x 2' drop-in troffers, each of which has two Cree linear LED arrays above a removable lenticular panel.

We probably could have used just two troffers to light the whole room. Flick on the switch, and SHAZAM! WHERE ARE MY SUNGLASSES!? Honest, you could do surgery in there, it's so bright, and there are no 'not bright' spots anywhere.

The attached photo doesn't do them justice.



Mike Halloran
Pembroke Pines, FL, USA

RE: LED external lighting

I was involved on a job late last year that used a large number of Cree 304 outdoor flood lites, they preformed well, virtually no installation problems that I knew of and their performance, based on light output versus energy consumption, was better than promised. One of the engineers commented that if he'd known of their capabilities he would have used fewer fixtures.

I was at the site recently and according to the site electricians, still no issues with them. There were some other LED fixtures installed at the same time by another contractor, these were smaller surface fixtures at each doorway, that had poor uneven lite and nearly a 100% failure rate since install.

I was on site to do a power survey, as the supplier of the "cheap" lites (I don't know whose brand) insisted the problems were due to "power problems". The power was fine, and there did not appear to be any issues with other electrical equipment installed at the same time as the LED lighting retrofit was done.

Hope that helps, MikeL

RE: LED external lighting

Hmmm... might want to check this out.

http://www.cpsc.gov/en/Recalls/2015/Cree-Recalls-L...

Cree LED recall...


"You measure the size of the accomplishment by the obstacles you had to overcome to reach your goals" -- Booker T. Washington

RE: LED external lighting

(OP)
Thanks all for your thoughts.


jraef,

Link is down but will have a look.

I wonder - was it a voluntary recall? Oh, the suspense!

RE: LED external lighting

(OP)
OK, the link is back up - it's a fluorescent tube retrofit / replacement rather than an integrated luminaire. 'Made in China'.

Curious - how tough are the US authorities on forcing companies to announce recalls? This one sounds like it was voluntary.

RE: LED external lighting


MikeHalloran:

How much was the cost of the 4x individual replacements?

RE: LED external lighting

The 2x2 dropin troffers were about $100 each, from Home Depot, which doesn't carry them anymore.

I suspect HD dropped them because there was some confusion and disappointment. While they are nominally dimmable, a regular dimmer in the AC feed won't work; it just makes them flash. No, make that FLASH!.

Each troffer has a separate termination where you supply a variable 0..10 VDC brightness signal. The required DC supply, extra DC cabling, and dimming controls (including wireless remotes) are listed at unattractive prices in various manufacturers' catalogs, but do not seem to be available from retailers, or even distributors, unless you are putting in a control system for a large building.

I sort of gave up on dimming, which was SWMBO's first request, because the switchbox is literally cast in concrete and there's no room for extra stuff. So she will live with manual ON/off, and wear her sunglasses in the kitchen.

Mike Halloran
Pembroke Pines, FL, USA

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