Completed 12V LED bulb, and some fun

[Rover]

Welcome to round 2 of my trials of building a 12 volt LED bulb with comparable brightness to a 120 V CFL. The first round was a 56 LED (SMD 5050s) . This time it is a 96 LED , dual wattage version.

Materials:
96 5050 SMD LED's cut into 8 strips with 12 LEDs from  a 300 LED 5M strip. Each SMD has it own 151 ohm resistor in series with the 3 LEDs on the SMD (the LEDs are also in series on the SMD)

Misc. PVC in this case 2 couplers for 2" pipe joined together with an internal piece of 2" , and some reducers for cap and base attachment
Used base from a CFL, only the metal part, built my own stage on top of the metal base.

Pic 1. Roll of LEDs purchased, built base, and the light tower (PVC couples drilled to reduce the insulation effects of the PVC, each LED will sit above a hole)

Pic 2. LEDs mounted and wired, top cap built with an integral SPST switch (will be used to switch from 48 to 96 active LEDs . for dual wattage)

Pic 3. The completed bulb

Stats:
wattage ~ 22W/11W @ 12V

To come... comparison of this one, against previous and a bunch of other bulbs

[Rover]

... And now for the comparisons, the fun

Here are  the bulbs , from left to right
1. 15W 12DC commercial incandescent bulb (yes they do make them, used on older boats, bought at West Marine for my boat)
2. The famous 5W 12V Harbor Freight CFL (cover removed)
3. A commercial 5W 12V 36 SMD LED bulb , purchased off of EBAY (I kinda liked these until I started building my own)
4. My original 56 5050 SMD LED bulb, ~ 13-14W @ 12V
5. My new dual wattage 48/96  5050 SMD LED bulb 11/22W @ 12V
6. Typical 14W (60W EQ. ) 120V CFL
7. Typical 23W (100W EQ. ) 120V CFL

Disclaimer: All of this is subjective, there are no numbers, I'm not going to mention lumens, etc, because I can't measure them

Comparison technique: Static exposure photography using my Nikon DSLR D90 (f4.8, 1/60th sec , ISO 400 EQ. ) .

Note, because I stopped down exposure to get the best comparison differential, images do not reflect actual brightness as when in use, however they do show a distinct visual difference in what I'm going to call "Subjective Brightness" ... kinda fun.

 15W 12V incandescent
 
 Harbor Freight CFL
 
 Commercial 5W 12V 36 LED
 
 My 56 SMD LED bulb
 
 My New 96 SMD LED bulb , 1/2 power , 48 active
 
 My New 96 SMD LED bulb , full power , 96 active
 
 14W 120V CFL
 
 23W 120V CFL
 
 
 

[Rover]

Nuts, I didn't include the bulb pictures

Here are  the bulbs , from left to right
1. 15W 12DC commercial incandescent bulb (yes they do make them, used on older boats, bought at West Marine for my boat)
2. The famous 5W 12V Harbor Freight CFL (cover removed)
3. A commercial 5W 12V 36 SMD LED bulb , purchased off of EBAY (I kinda liked these until I started building my own)
4. My original 56 5050 SMD LED bulb, ~ 13-14W @ 12V
5. My new dual wattage 48/96  5050 SMD LED bulb 11/22W @ 12V
6. Typical 14W (60W EQ. ) 120V CFL
7. Typical 23W (100W EQ. ) 120V CFL

[zap]

Excellent... EXCELLENT... EXCELLENT post Rover.

Fantastic comparison pictures!

[DamonHD]

I think it may be even better if you could have at least two at a time of the bulbs lit in the same pic so that autoexposure and colour-balancing stuff anywhere in the processing pipeline doesn't hide the differences.  But it's pretty clear even as you've done it, I think.

I'm still just amazed that a few well-placed mW does for our landing nightlight...

Rgds

Damon

[Rover]

Yep, I thought about putting 2 or more side, but I also thought that doing so may muddy the ability to show an individual bulbs subjective brightness as light output from the adjacent bulbs would interfere with each other. It would show relative point brightness thoug.

I've been doing this for fun, and I like the LEDs, when comparing the 23W 120V CFL to my latest one runnning at ~21 to 22W @12V , they appear to be close in brightness. For practicality and expense though the CFL wins hands down.

If I wasn't running my outdoor light ridge @ 12V , I'd stick with the CFLs, but since I couldn't find any high intensity 12V lights I buit these. Using the prebuilt LEDs strips with the included resistors, does make assembly much easier, but out of the 22W taken by my bulb, a 1/4 of that is dissipated by the resistors.

Still. I'm going to buid some more but probably smaller ones, I still have ~ 200 left to play with

 

[zap]

... but out of the 22W taken by my bulb, a 1/4 of that is dissipated by the resistors.
 

Any plans to use/try a driver?

[Rover]

Yep, I've contemplated it. Would mean I would either have to change the type of LED, or solder 100+ SMDs (not a fan of that option).
Or I could desolder the resistors and jump across and try to work something out that way with a driver.

Any case, a ton of work

[zap]

It's hard to see in your photos of the strips but if you went with a driver... could you just draw a new trace around the resistors with a Circuitwriter pen?  It would negate any desoldering although you might be able to just knock them off without any heat.
I've had one of those pens for a few years now and that stuff goes a long way.

[Rover]

The strips are painted, still too much work . I'm looking at different approaches

[ghurd]

I had a look at an item using (what I think were) 5050 LEDs a couple days ago.  Pretty nice.  I was impressed with the Kelvin and angle.

The new bulb looks Great!
G-

[Rover]

Thanks G,

The 120 degree beam angle, helps qute a bit with the luminosity. What I would like to find (and won't) are  industrial fab strips that have a certain number of SMD without the resistors.

I'm also thinking Cree, but high intensity LED's  such as those would still show as distinct points of light. I llike the fact that at about 15 ft, my bulbs look like a unified source as opposed to a number of distinct points.

Thanks on the advice previously about adding a high wattage resistor, I've decided , for now, not to go that route. I will control the voltage going into the bulb.



 

[wooferhound]

Hey Rover
You have a great project here, I added it to the FAQ under the heading of Making LED Lights

[Madscientist267]

Something I've found that works as an excellent hi-power LED driver is the small buck converters commonly used as USB chargers for use in a car.

They might not be able to directly put out quite the power you're talking here, but a little bit of modification and you'd have yourself a nice driver for cheap.

I'm using one to drive a 5W LED, and it's amazing how efficient that thing is. Wide input voltage range too!

Steve

[Rover]

Yep, I use 150W buck/boost  to steady the voltage to the lighting (LEDs)

[Rover]

Hey Rover
You have a great project here, I added it to the FAQ under the heading of Making LED Lights

Coo,l thanks Woof