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FieldWorker

Driverless (not really) Smart IC COB LEDs for AC mains.

Hey there, I have not found much discussion on this board regarding these "new" COB LEDs which come with a built-in driver. (Also called DOB, driver on board)

 

It's easy to work with these lights; just put AC power on them and they'll work. They are available in different wattages and colors, from "blurple" to red, and 3k, 3.5k etc. A downside for humans is that they flicker. It's not visible to the eye, but in your peripheral vision you may notice it. It also may become apparent with faster moving objects.  The cost of one unit is about €1-€2.50 so they are indeed very cheap.

 

They get hot as hell, and do some kind of self-regulating when they do. Using a CPU cooler is very effective and cools them right down. 

 

Here are some pictures of my test build. 50W 3k COB unit. 

 

large.IMG_20181022_003922.jpglarge.IMG_20181022_003507.jpg

 

 

Here is a comparison picture from my webcam. The first picture is CMH 315w only, the second picture is just the LED. It puts off quite some light as you can see. Unfortunately the manufacturers don't provide PAR measurements but according to some things I've seen they should be pretty efficient when cooled.

 

large.00958.jpg

(Edit: The holes in my netting are about 8.2 cm :) )

 

I've read reports of some blowing early, but also of people who have been using them for a long time. 

 

Has anybody here used these lights for a full grow/veg/whatever? Maybe we can start some discussion here. I browse a few forums but this is the most intelligent place and I've not found any threads about these here. 

I might be interested in building a veg light, and since you see the brightness and price point, you might also be interested in messing around with it for fun!

I am waiting for some "3rd generation" COBs which have solder-free connections (halleluja)  and are supposed to function even better. Once these things get rid of the flicker (and there is no reason that they can't, it might cost a bit more) they might become a force to reckon with at these prices.

 

Cheers

Edited by FieldWorker
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@FieldWorker  Do my anxiety a favour and find a way of clamping that cable down and even better if you can get the terminal block enclosed. :)

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Just now, monkeypig said:

@FieldWorker  Do my anxiety a favour and find a way of clamping that cable down and even better if you can get the terminal block enclosed. :)

Haha :) Yes, the final builds will definitely have to be a lot less "ghetto". Impatience got a hold of me. (In the end I did put some hot glue on the solder joints)

You might also notice the lack of screws, I just used Heatsink plaster.  I found a cheap product called "Stars 922" which was supposed to bond really well, and it does. Drill & tap is certainly recommended.

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Always thought these are very interesting.. like a bit of ghetto myself. 

 

I'm sure I heard that an earthing circuit to the heat sink was a good idea because of the flimsyness of the rear of the cobs coating. Or something to that effect. Mains voltages are VERY close by! (Probably the wise words of bigclivedotcom).

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Doesn't look appealing, the wiring that is...

 

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Right, the wiring is retarded (exposed mains on these) and these lights are absolute junk. Anyone wondering if they should get them, just don't do it. You're better off with even blurples. If I could edit or remove this thread, I would. They are  not "pretty efficient" when cooled properly. In fact they are a straight up hazard.

I've since graduated to building proper high efficiency strip leds with proper parts. 

:)

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On 26/11/2019 at 9:54 PM, FieldWorker said:

Right, the wiring is retarded (exposed mains on these) and these lights are absolute junk. Anyone wondering if they should get them, just don't do it. You're better off with even blurples. If I could edit or remove this thread, I would. They are  not "pretty efficient" when cooled properly. In fact they are a straight up hazard.

I've since graduated to building proper high efficiency strip leds with proper parts. 

:)

Hi mate, you got me interested in the last part of your post.

Have you got a thread showing how and what you used for your strip LED's?

if not, would you mind making a thread?

I think it would be quite informative

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On 1/24/2020 at 9:43 AM, Subutai said:

Hi mate, you got me interested in the last part of your post.

Have you got a thread showing how and what you used for your strip LED's?

if not, would you mind making a thread?

I think it would be quite informative

 

I have to say, I'm not really one for making threads but maybe I can point you and those who are interested to the right direction. I would be reinventing the wheel by writing it all again and it is quite a lot of information. To be able to build LED you need to learn a bit about light, electricity, thermals (heatsink/cooling) and whatever else you don't know that is involved in the process. 

 

GrowMau5 and LEDGardener's video series on youtube are very informative and will basically teach you everything you need to know. 

I watched that stuff out of interest once and was turned off by the (apparent) complexity. Took me a few times watching it to understand.

 

Basic high efficacy strips can be bought by consumers on websites like Digikey, Mouser.  Popular strips for DIY are Samsung strips with LM301B diodes or Bridgelux EB Gen 2/Gen 3 strips, for example.  The drivers used by most people are MeanWell HLG series.

If you google those terms + "build" + "forum", you will also find a lot of information. 

 

Personally I use the Bridgelux EB Gen 2 strips, attached onto aluminium U-channels with thermal adhesive tape. All my LED drivers are MeanWell. I also have COBs but strips are better.

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thx mate

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