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Anyone tried these

dean

dean

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6 Apr 2012
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Location
Warrington, Cheshire
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Anyone tried these type of lights ?

What would I need to buy to be able to use them

Could they be dimmed ?


Regards
Dean
 
Well would be a laugh if it does a good job, isn't it.. :) I have no idea, but COB LED is getting more common as said also in AC 220 spots. The contstrution/placement of the chips makes it ideal for bundeling the light.. Haven't tried them yet, but was looking and wondering also, the specs they give seems promesing..
 
Looks to be interesting indeed. I am imagining a Flex mini DIY version. :)

zozo.... balls in your court.
 
What i find rather questionable is point 6. 3500 high luminance which says nothing to me and bellow it says luminious flux 480 lm which is rather low again.
But for a slow burner they might do... I red old article where poeple grew aquatic plants under those CCFL bars which are used for PC and Car cosmetics. :)
 
Hi all,
zozo said:
I have no idea, but COB LED is getting more common as said also in AC 220 spots
Click to expand...
I bought some 12V DC (transformed from 240V AC) 3W G4 COB LEDs as a possible replacement for the 20W halogen light sources in our compound microscopes.

I needed a physically small lamp that was dimmable (it had to be a G4 fitting, and there is very little clearance for fitting the bulb). They dimmed without changing colour (halogen lamps become a lower colour temperature as they dim), and they looked really bright as a point light source, but they weren't quite bright enough to replace a 20W halogen G4 lamp.

cheers Darrel
 
dw1305 said:
Hi all, I bought some 12V DC (transformed from 240V AC) 3W G4 COB LEDs as a possible replacement for the 20W halogen light sources in our compound microscopes.

I needed a physically small lamp that was dimmable (it had to be a G4 fitting, and there is very little clearance for fitting the bulb). They dimmed without changing colour (halogen lamps become a lower colour temperature as they dim), and they looked really bright as a point light source, but they weren't quite bright enough to replace a 20W halogen G4 lamp.

cheers Darrel
Click to expand...

Yes indeed those comparisons they make whit leds replacing other common lightsources are is rather questionable. The whole industry is still in it's infancy.. And i also have rather serious doubts about the given specs and how they compare.. As with the smd leds i use it should be compared to others be 9360 lm i have above my high tech tank now, but i doubt this sincerely not to be true. Above my slow burner i use 5 high power 15 watt ledspots runing on AC 220.. wich should be compared 5 x 780 lumens and i also doubt this. but in the end what i'm using it for it's more than enough as far as i can see and have to dim both setups to prevent algae growth.

Because i kinda doubted the given specs to begin with i went for the highest output i could find, to much is always dimmable, not enough is always a mis.

So rather always go for the highest if you have a dimmer and forget about the comparing specs. :)
http://www.ebay.com/itm/Mini-G4-G9-...Crystal-SMD-COB-Lamp-Light/111930389685?rt=nc
 
Once again it shows the words quality, LED, China and Ebay cannot be used in the same sentence.
 
Seller says that they can't be dimmed
But video clearly shows they can

I may try some just for the fun
I use metal racking that has all metal shelves so just stick them to underside and job should be a good one

Any suggestions for cheap but not explosive power supply


Regards
Dean
 
dean said:
Seller says that they can't be dimmed
But video clearly shows they can

I may try some just for the fun
I use metal racking that has all metal shelves so just stick them to underside and job should be a good one

Any suggestions for cheap but not explosive power supply


Regards
Dean
Click to expand...

Well as what the video shows he is obviously dimming them, car battery power also is not a very constant and fluctuates between 12 and 16 volts.. And as he demonstrates they run on different voltages and probably for the long term best on a constant current 12 volt power supply. A PWM dimming device doesn't change the current, it dimmes by pulsating the power on and off in a adjustable very high freqeuncy.

Any 12 volt power supply with the adequate output will do, they are 6 watt per piece, so you should add up all you want to connect and use a 12 volt power supply equal to this or higher. Most regular small power supplies give Amps as specification instead of Watts.. Watt = Amp x Volt, so if the power supply states 1 Amp then 1 Amp x 12 Volts = 12 Watt can be run on that supply.. In your case that would be 2 strips max.

For cheap and fun experiments like this i'm a regular customer of Banggood.com, they are kinda the DIY heaven to go to if you're looking for cheap materials and tools to play with. :)
 
dean said:
So this is not going to work as a dimmer ?


Regards
Dean
Click to expand...
Yes they do work as a dimmer/controler they are actualy the only way for SMD led dimming without issues. For examplle the known TC420, 5 channel programmable LED controler. Actualy is a programmable 5 channel PWM device you can not only control SMD leds with it it also could control motors and fans running on DC voltage.. :)

In the link it says PWM Motor Controler, in an other link it could be called PWM LED controler.. But it doesn't make a differnce PWM is PWM, if it is for LED or Motor doesn't make a difference. It probably is put that way for the buyers convinience to give it the name they are looking for.. But it also confuses, they still both do the same thing.
https://en.wikipedia.org/wiki/Pulse-width_modulation

But at first glance i wasn't 100% sure if it would dim COB leds, because i do not know how they pull current.. But since it's running simply and direct from 12 volt car battery my best guess was it should work. :)
 
zozo said:
Yes they do work as a dimmer/controler they are actualy the only way for SMD led dimming without issues. For examplle the known TC420, 5 channel programmable LED controler. Actualy is a programmable 5 channel PWM device you can not only control SMD leds with it it also could control motors and fans running on DC voltage.. :)
https://en.wikipedia.org/wiki/Pulse-width_modulation

In the link it says PWM Motor Controler, in an other link it could be called PWM LED controler.. But it doesn't make a differnce PWM is PWM, if it is for LED or Motor doesn't make a difference. It probably is put that way for the buyers convinience to give it the name they are looking for.. But it also confuses, they still both do the same thing.

But at first glance i wasn't 100% sure if it would dim COB leds, because i do not know how they pull current.. But since it's running simply and direct from 12 volt car battery my best guess was it should work. :)
Click to expand...


I've just ordered two from you link

Just downloading the banggood app then I'll search for power supply

Thank you very much for the help and info

Is there a diy section to add builds and experiments



Regards
Dean
 
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