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 How to use the relatively new 12 volt MR16 LED lights -------Update -another conversion!
EXPY37  [Team Member]
1/8/2012 3:32:19 AM
How to use the relatively new 12 volt MR16 LED lights in various applications for expedient light.

Picked up a nice LED version of the old halogen MR16 lamps that are used in track lighting and elsewhere. You all know how hot the MR16 style lamps get and they draw about 40 watts +/- depending on the lamp and application.

Here's a pix of the halogen lamp.



Now here's a pix of a typical new LED lamp. This one is a Samsung 35 watt equivalent and uses 6 watts at 12 volts dc or AC [!] and outputs 370 lumens.



Years ago when I worked for a computer co I carried with me a compact work light that had a wall wart 12 volt transformer and a light asm with a magnetic base and switch, a gooseneck and an small lamp housing with a no 93 bulb inside. A more sophisticated version of the small table lamps with a transformer base using the no 93 bulb that I thought were so neat way back then.

So for nostaliga I thought about buying an LED flashlight and putting the LED in the reflector, cutting off the transformer and running the wire to the flashlight housing. So I went and bought a flashlight ––-but also bought an MR16 LED lamp.

The flashlight mod will have to wait for another story because I modded the light to use the MR16. I've picked up a few of these lights at Dayton and other hamfests over the years so I'll prolly do the flashlight mod too if these's any interest.

Here's the trouble light disassembled... The no 93 bulb and the highly modern LED MR16 that's going to replace it. The old incandesent was OK but the LED will blow it away.






Now I'm testing it to see how much current it draws and that's a surprising low .45 amps at abt 13 volts dc. I simply soldered wires to the lamp pins. Easy.






Here's the lamp wired and put back together. I used new wire through the gooseneck.

I also reused the wire nuts, I guess I'm an envirowacko conservative...






The modernized trouble lamp on top of a remote IP power switch. I can sit here at the computer miles away and watch it turn on and off via an IP cam and that switch.







The lamp is very bright, the transformer doesn't seem to even get warm, compared to the old #93 bulb that drew over an amp and I often got burned by it when the magnet came unstuck and it would fall over on me. But I was damn glad to have it back then.

This is just one mod for these great new LED lamps and the uses for survival are limited only by your imagination!!!



If you have one of the transformer base lights [zillions were made] you can mod it just like this and you could put a cigarette lighter plug on the cord and bypass the transformer.

Always fuse the 12 vdc ckt...




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FordGuy  [Team Member]
1/8/2012 6:31:46 AM
if it is 12 v ac or dc, could you run them to every room of your house and light your home on 12 v in an emergency?
Surf  [Team Member]
1/8/2012 6:31:55 AM
tag
Duggan  [Team Member]
1/8/2012 7:10:56 AM
hmmm
piciphant  [Member]
1/8/2012 9:38:50 AM
does the lamp have a built in driver and what is the min-max voltage?
I got some led spot lights but they are dim at 12v so unsuitable for battery power, but work fine on ac xformer power.
mylt1  [Member]
1/8/2012 12:56:29 PM
1/2 an amp for those bulbs. hummmmm, this could be interesting. now that i am on 24's i will have a lot of extra time. i may try and use one of these as emergency lighting using either a battery pack using AA's or even some of the 18650s i have. might even build a "light box" using a larger 12v backup battery.
EXPY37  [Team Member]
1/8/2012 5:04:58 PM
Originally Posted By FordGuy:
if it is 12 v ac or dc, could you run them to every room of your house and light your home on 12 v in an emergency?


F-G, the light I used above runs on 12 volts AC or DC.

They're used typically in track lighting and those use a transformer from 110 ac to 12 vac to drive the formally halogen slidable/movable lights.

You could light a bunch of rooms on 12 vac or dc but it would likely require new wires run, etc. Running lower voltage isn't very eficient too.

I think the 110 vac operated LED lights are more efficient because the ones I've looked at recently have a bunch of LED 'wafers' in series so that no swiching converter/rectifier is needed to be built into the lamps as is the case with the 12 volt ones.

The strip undercounter lights that use 6 or more discrete LED's that Lowes and H-D sell do have a switching power supply built into them that has losses. They work well though and we use them in the container.

Now there are LED track lights that use 110 vAC directly, to make things more complicated, and we use 3 of them over the small kitchen counter and they have worked well.

I can see I'm getting off track...

So, I don't think it's a good idea in most cases to run the 12 volt lights around a house even if you pre-wired it for 12 volts. Too much loss vs other options.






EXPY37  [Team Member]
1/8/2012 5:12:18 PM
Originally Posted By piciphant:
does the lamp have a built in driver and what is the min-max voltage?
I got some led spot lights but they are dim at 12v so unsuitable for battery power, but work fine on ac xformer power.



I believe they do have a built in driver and I may take one apart and post pix.

The transformer with that old timey work light above measured about 15 volts.

These lamps were designed to work with normal track lighting power supplies/transformers and since residential power can vary from 105 to 130 volts -about, I think they can put out good light over a wide range. They may be internally regulated as well since that would be easy to impliment in their driver and wouldn't make much of an efficiency difference.

I can't offer an explaination why your LED doesn't work well on DC except it may have something to do with the way power is rectified on the front end of the ckt.

How old are they?


echomancer  [Team Member]
1/8/2012 8:38:45 PM
Any idea of how RF quiet these bulbs are? I bought some commercial 12v LED lanterns from GoalZero, but when I turn them on, they completely hash out anything from 110-150mhz within 20 feet of them, and that kills the all important 2m ham band!

Good write up!

EXPY37  [Team Member]
1/8/2012 11:25:16 PM
Thanks.

I just looked at the lamp in the original post w/ a spectrum analyzer w/ a 20" whip antenna on the input, 0 atten, at 150 mhz at -100 dbm in a narrow bandwidth, and saw nothing. Same in a 2 mhz BW at abt -90 dbm or so.

Took pix.

When I turn the room flourescent lights on and off, the noise level comes up abt 10 db and you can clearly see the 60 hz ripple in the sweep.

Then I took an AM radio tuned to lower and higher parts of the AM band, turned the O-H lights off and put the radio next to the lamps unshielded cord and could not tell any difference with the lamp on or off. Broadcast bands were coming in strong so I think it was a good test when I tuned away from a station.

So I'd say the lamp is very quiet.

EXPY37  [Team Member]
1/9/2012 12:06:27 AM
Ran a test to answer the min-max voltage question and the results are interesting and encouraging.

Ran the lamp from 8 to 16 volts and the current decreases as the voltage increases as would be expected for a regulated driver. No change in brightness.

Below 7 volts the lamp just starts getting dimmer but usable. No noticable flickering.

I took a lamp apart by popping off the lens in the front, removing the 2 screws holding the LED ckt bd and lifted the board.

There's a connector that makes this easy.

Under the LED board is a board that goes down to the pins and an inductor, an electrolytic cap and some other parts are visible sticking out of the potting compound.

These lamps are made by Samsung BTW.

piciphant  [Member]
1/10/2012 5:22:41 PM
that answers it, my lamps are just leds in series for xformer use.
EXPY37  [Team Member]
2/2/2012 3:58:48 AM
Here's another conversion. I didn't do it yet but this conversion can easily be adapted to run on any power tool 12 vdc battery, as these LED lamps only draw about 500 ma at 12 vdc, by adding another connector in the base.

My SO had one of these old timey desk lights that were popular before many here were born. They use the same 12 volt auto tail lamp and base transformer as the first project light above.

So tonight I took a few minutes to take it apart, check it over and install another LED lamp like the one above.

Note, if you are using any kind of LED lamp, explore removing the various lenses, milky diffusers, etc, because those marketing dodads can cost 1/3 of the light output to be lost and never get out of the lamp bulb assembly.

Here's a photo of the desk light apart, you can see the old bulb, the new LED one some of the parts of the old socket from inside the lamp head, and misc parts and pieces.

Oh, I remember what these were often called, "Tensor" desk lights...

You can see the new wire I ran through the flex arm, I got a nice roll of this wire at a flea mkt way back. Only one wire is req'd because the frame is the return. Of course there is a 12 vac transformer in the base of these lights so they won't create interference in a radio, etc.





Note the small rectangular LED lamp assembly next to the round one below, they run on 12 vdc and draw only about 130 ma and are available at Lowes for abt $8. They vary in brightness with voltage since they don't have an internal regulator circuit. Very bright and a great deal for $8!

I've removed the lens disk in this pix of the round LED.

Back to the conv...





After the wires were soldered to the pins on the LED lamp, I stuffed it back in and it was amazing how the dimensions were such that everything fit perfectly.

Of course, I planned it that way...



Wal Mart [used] to have some aquarium sealer that is like ordinary silicone based adhesive but this tube must be 8 yrs old and has never hardened and is always great to use. I saw some on ebay too for $5 a tube. Great stuff and it will hold the LED in the shade. Called Aqua-Tech Aquarium Sealer, good for the SHTF kit. Ebay.





Here's the finished product. The light has a dimming switch that is about a 9vac tap in the base transformer and since the LED has a switching boost/buck reg in the base it doesn't care if it sees from 8 volts to 16, it stays the same brightness and when you hook the lamp to a power supply, you can see the current drop as you turn up the voltage.

In other words, no matter within the op range of the lamp, it always draws the same POWER [watts] it justs drops the current as voltage increases.





EXPY37  [Team Member]
2/2/2012 4:20:26 AM
Another tip.

See the Dewalt mini lithium impact driver in the photo above?

It has a Harbor Fright step drill in it. That is the BEST way to ENLARGE holes vs drilling them. Less likely to rip your hand and need Crazy Glue to fix and doesn't bend sheet metal all to hell.

We use them to build with 14 ga steel with the larger Dewalt 1/4 drive impact and they will enlarge holes in even multiple thicknesses fast. The trick is to keep the RPM's low, predrill a small hole, enlarge with the step drill, and not use them fast in a drill, etc, so as not to burn the edge. The regular [bigger] 1/4 impacts are great, especially if you have 1000's of screws to drive or tighten, like in a standard or Quonset bldg.

The step drills are often on sale for a kit of 3 sizes for $9. I stock them deep.

Wouldn't be w/out them.

TaylorWSO  [Life Member]
2/2/2012 8:48:41 AM
I will say it again, I love your post. They are "geeky" to me as I'm a caveman but they are very easy to understand and the projects are outstanding. Keep it up.
EXPY37  [Team Member]
2/2/2012 10:26:31 AM
Appreciate your comment Taylor, I enjoy sharing these little 'adventures'.

Lifesaver  [Team Member]
2/2/2012 11:11:19 AM
I see a(nother) trip to Harbor Freight in my future. Thanks for the tip about the step drill. As a HAM, I'm always fabbing up something. The light is great work. I may make one of these for mibile ops. It oculd run off the same power supply (12 v) as my radio.
FlatlinesUp  [Member]
2/2/2012 12:58:18 PM
+1 on the HF step drills. GREAT tool for the $.


You sir, are a geek. And are welcome in my AO anytime. :D
SandHillsHillbilly  [Team Member]
2/3/2012 5:21:21 AM
Those little board mounted LED assemblies I found them in different configurations and color at the local AutoZone store. They are in the ricer dress up isle with all the gear shift knobs.
SFC_77  [Member]
2/3/2012 11:41:50 AM
EXPY37 that was a great post.. Informative and documented well.

Thanks again. As a fellow geek, it's like porn......
mcnielsen  [Team Member]
2/3/2012 12:26:15 PM
Where did you get th mr16 LEDs. Do you have a good, inexpensive source for them? Looking to swap out all my halogen bulbs and save a mint on electicity costs
EXPY37  [Team Member]
2/3/2012 6:24:45 PM
Originally Posted By mcnielsen:
Where did you get th mr16 LEDs. Do you have a good, inexpensive source for them? Looking to swap out all my halogen bulbs and save a mint on electicity costs


The best place I've found for innovative LEDs at usual places is at Lowes. I forget how much the MR16's cost but it was around $18+ maybe. We hope to go to one next week and I can check. Home Depot doesn't have much that's good.

LEDs aren't inexpensive right now but watching their capability vs price for a long time, things are getting much brighter for us who want to start applying them.

Re the small flat one, I agree that's the one like the ones I've seen for the ricers on ebay. I bouught a couple on ebay abt 2 yrs ago but they weren't as good as these by a long shot. I'm going to the car parts place and see what they have.


Thanks again for the kind comments, I enjoy doing this kind of post -vs the doomer ones...



EXPY37  [Team Member]
4/2/2012 11:59:17 PM
Wanted to update this post to say that Lowes has apparently pulled all the LED lights like the one in the first post for "investigation".

SandHillsHillbilly  [Team Member]
4/3/2012 12:51:06 AM
Originally Posted By EXPY37:
Wanted to update this post to say that Lowes has apparently pulled all the LED lights like the one in the first post for "investigation".



Investigation for what?
EXPY37  [Team Member]
4/3/2012 12:53:53 AM
Originally Posted By SandHillsHillbilly:
Originally Posted By EXPY37:
Wanted to update this post to say that Lowes has apparently pulled all the LED lights like the one in the first post for "investigation".



Investigation for what?


Don't know. I called stores a couple parts of the country hunting more and to see what's going on. One lady I talked with in the east used the word 'investigation' and was rather frank abt it vs stores in the west who were cagey and just said they were all pulled off the shelves.

So IDK.

Mine is fine and I wish I'd bought more.

SandHillsHillbilly  [Team Member]
4/3/2012 12:55:39 AM
I did find this interesting maybe this is why.
http://www.stolpje.nl/~cees/led/led-investigation.pdf

ETA: Lowes online shows a "STOP ALERT" on the page for that lamp. I have no idea what that means.

Also Samsung is not showing in their product line up either. They show a 120 volt version.
http://www.samsung.com/us/appliances/led-lighting/all-products
EXPY37  [Team Member]
4/3/2012 12:57:57 AM
IIRC, I looked roughly at RFI from that lamp and found it benign.

The electronic ballists in the 48" troffers in my lab are another horrible story...

EXPY37  [Team Member]
5/30/2012 12:27:36 PM
Still working great!

mcnielsen  [Team Member]
5/30/2012 1:45:54 PM
Originally Posted By SandHillsHillbilly:
I did find this interesting maybe this is why.
http://www.stolpje.nl/~cees/led/led-investigation.pdf

ETA: Lowes online shows a "STOP ALERT" on the page for that lamp. I have no idea what that means.

Also Samsung is not showing in their product line up either. They show a 120 volt version.
http://www.samsung.com/us/appliances/led-lighting/all-products


You pretty much need an electrical engineering degree to understand this but the way I read it is: The LEDs will mess with your electrical system if you have too many of them in one system... Amiright?
SandHillsHillbilly  [Team Member]
5/30/2012 5:19:08 PM
All electronic devices have to meet a specific limit of spurious emissions. If it exceeds those limits it can interfere with other electronic devices. If a device exceeds those limits then the FCC can remove the product from market.
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