I was comparing lumen output to a similar wattage quantum board 11,000 lumen maybe im wrong there. I dont know enough about led efficiency to make a comparison nor would i. @dbrn32
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I would have to recommend against doing anything with leds like that. It seems cheaper, but most people aren’t happy with the performance out of them.
Depending on what you’re looking for, there are some very good inexpensive leds that run pretty good in the 30-40 watt range. Citi 1212’s and vero 18’s can both be purchased for under $10. At that power level I’m sure you can find some reasonably priced radial heatsinks as well under $10. An hlg-185 will run you about $50. If you can round up the rest of equipment cheaply, I wouldn’t be surprised if you could build that out for around $200. That’s 5 cobs, so around $40 per cob.
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No worries. Figure a 145 watt quantum board would have total flux of about 23,000 lumens.
That’s version 1, I think about 6% more for version 2 288
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@dbrn32 thank you for the info. And you are right. I must of been looking at specs for a smaller qb. I will not be wasting my time. On another note. What would be a good qb fit for a 3’x6’ area. Do qb’s have good canopy penetration? Im looking to spend some loot end of year and i havent done alot of research on qb’s and was set on a big vero 29 cob build but after reading some of your stuff on qb im maybe changing my mind
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Nothing wrong with the vero 29 in my opinion. I think you’d be happy going either direction. I think in that size room you may be at slight advantage going with cobs, or using something like the qb 120 or 132.
It would be a little light, but I’d probably try running with two bars of 4 lights either way. 4 cob bars of 70-75 watt vero 29 or even citi 1818. Or 4 qb 120’s on each.
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I was just looking…4 -qb 120 for about 160.00 i would get 8 total plus drivers. I can get all the aluminum angle i need for free. Do the qb’s require a heat sink or do they run cool enough? Sorry, i normally do more research before hand but i knew about qb’s but never really considered them.
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Where you located? Last I seen the 120’s were available in 4 pack on amazon for $130. Hlg rates them as not needing heatsink at 2100ma or less I’m pretty sure. Hlg-240h-c2100 does 4.
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It must of pulled up a higher priced seller. Lol 124.50 for 4 qb 120 and 133.00 for 4 qb 132.
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The light will run on 110v AC. No power supply needed. These driverless Cobs like the one you’re looking at don’t put out much light compared to the amount of heat they give off which means they need a big heatsink. I experimented with them for a few months recently and scrapped the project because they just don’t cut it. I see from the description on Amazon, they won’t give many details. I’ve seen them on Alibaba and they do actually draw 70 Watts. I’m just not sure you’re getting 70 Watts of light. I would mail you all 10 of my unused 50 watt driverless Cobs if we could share contact info. Which we can’t. If you’re going to try them, I would suggest buying just one and a big pin type heatsink for it.
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Honestly, I wouldn’t trust driverless cobs with yours.
There’s too much heat to lose as you first take mains to DC, then rectify it, then run the cob.
That heat is inefficiency, and a lot of it as so much electrical energy is turned into heat at the expense of light. Colling then becomes more important which means more costs in heatsinks and/or fans, life of the cob will be lower, they are a false economy and, well, you would be better with my sub-$40 cheap led setup in my opinion.
I don’t trust these things, mainly because the extreme heat from driving and then the cob is going ti be an issue.
Like with these cheap “grow lights”, you can do better for either the same money or, literally, slightly more.
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@dbrn32 mate it’s completely off topic, but would you be keen to help me with a kitchen light project. My wife wants a hanging LED light bar above the new kitchen island, bought it’s a 700 dollar light. I think we could do something with a couple of strips and some nice powder coated aluminium for a fraction of the cost.
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Practicality! I love it!
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Got a picture of what she wants?
I used to make these things, SMD5050 strip, ideally 24v, works perfectly with a meanwell CV driver.
All depends on what you want, whether you need it dimmable, the need for a diffuser, etc.
That’s basically what’s she’s after. I was hoping I could hide the driver in a small ceiling space I have abouve the walk in pantry and possibly run a dimmable driver to a dimming light switch
you can see up top where the original 3 pendants were going to come out. That’s where the light bar will be centered. The ceiling height at that point is about 3.3 meters but I’d say the bar will be hanging at least 1.8m from the floor
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Lemme do some digging around. If I can find an aluminum profile that fits with lens shouldn’t be too big of a problem.
Does it have to be 1.8 meters long? Not really worried about the leds, but finding the profile longer than 4’ may be an issue.
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I took this screenshot, check this place out.
I’ve never used them for anything, but they have some very neat stuff. It looks like they have everything setup to go together nice and cleanly. And for $25 they have those controllers that look to be operated from remote. If you want dimming, that would definitely be the way I would go. Dimming with standard wall dimmers can be very tricky.
Anyway take a look and let me know what you think. If you’re interested, drop them an email or something. I’ll look around for some other options too.
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I could point you to a pre-made fitting, with dimmer built in if you wish, made from solid brass in a choice of colours from dark aged brass to nickel coated to chromed to painted but I know you wouldn’t like the price.
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