How I Do my LED Spots
DISCLAIMER: Do this at your own risk. I do not recommend
advise that you use this procedure. I only admit that I do. Electricity
can bite so you need to be careful.
I got this idea from the Crazy Light Lady. Check out her site for more LED stuff!
My MR-16 LEDs are first hot glued into half of a 80mm fillable ornament ball.
Then I melted two holes in the other
half for the wires using a soldering iron.
By using a soldering iron and not a drill you don't crack the plastic.
Then I pushed the socket onto the pins (Some
folks just solder wires directly to the MR16)
I got the sockets off Ebay but you can also get them from Best Hong Kong (shipping is large).
Next I hot glued the half together. You
should be a little quick on this as
the hot glue can cool and before the halves are together.
I then took my hot glue gun and ran around the edge to seal the globe and
sealed the wires.
I used a 3" PVC 45 degree elbow as a holder.
The PVC elbow is the thinner drain type.
I will paint the PVC elbow with black plastic paint.
I can aim the spot up or down and the glue around the edge holds it in place.
The parts to the prototypes are:
1 1-1/2” PVC Cleanout (Plumbing) .55
1 1-1/2” PVC Female Adapter (Electrical) .72
1 - 60mm Acrylic Ornament Ball (half) .42 here
1 - MR16 Connector .40
LED Wholesalers (eBay)
The Second Prototype just adds a 1-1/2” to 2” adapter. This makes the MR16 recessed. The same 60mm half ball fits perfectly inside the 2” PVC.
The Total for the first prototype is $2.09. It’s not cheap, but it seems like it will work well and last a long time.
Richard Does his LED Spots
Visit Richard's site
are from Michael Miller:
Lights on Logan
Notes from Michael:
I have three of these "banks" for L/C/R
control of the colors on the house.
The color to throw on the house is determined by a mixture of red, green, and blue:
R = Red
R + some G = Orange
R+G = Yellow
G = Green
G+B = Aqua/Cyan
B = Blue
R+B = Purple
R+G+B = White
There are twice as many reds as green and blue because the red LEDs are dimmer.
The MR-16s are from Action and have 20 LEDs each. They are 12V AC (not DC) but will run on 13.8V DC just fine.
All are housed in a PVC electrical threaded adapter (glued in place) with an equivalent threaded plug from the plumbing department. The Action floods themselves are waterproof and need no additional protection on the front side. Each of those is bolted to a horizontal board and can be individually adjusted in the X axis. The entire group of 5 on the board can be adjusted in the Z axis. The Y axis adjustment is just how far away you put them.
PVC Flood Light Recipe
(1) Cantex 5140047 1 1/2" PVC Threaded Adapter
(1) Charlotte #106 1 1/2" Cleanout plug
(1) 1/4" x 1 3/4" bolt, 20 thread
(1) 1/4" nut, 20 thread
(1) 1/4" lock washer
(2) 0.062" Molex female crimp on sockets (Mouser 538-02-06-1103)
(1) short length of SPT wire
(1) tube of Goop Plumbing adhesive (comes in a purple tube and lists PVC and glass both on the back)
(1) Teflon tape
The 1 1/2" PVC threaded adapter may or may not be at your local Lowes/Depot electrical department. Lowes only had one when I was trying out the design and they never restocked it... you may have to order them from an electric supply (it's cheaper that way anyway-- only 0.60 each). The cleanout plug is readily available in any plumbing department, although at my quantity (120) I found it cheaper to order them online at only 0.40 each.
1) Drill two 1/4" holes in the PVC adapter. The "top" hole should be about 1/3 of the way between the support ring and the "front" (non-threaded) end of the adapter. The "bottom" hole should be behind the support ring (yes, that places it into the threaded portion).
2) Put the 1 3/4" bolt through the "top" hole from the inside of the PVC adapter. On the outside place a lock washer and the nut. Tighten.
3) Optionally (as pictured below) place three small pieces of the hook side of Velcro around the "front" inside of the PVC adapter. This will help steady the MR-16 (keep it from slipping) when it is being glued in place. Alternatively just use a steady hand.
Steps 4 and 5 assume you use the same adhesive as I did... if not, then follow the instructions for your adhesive.
4) Apply a bead of the plumbing adhesive on the rim of the PVC adapter and the MR-16 bulb. Let the glue stand for 5 to 10 minutes.
5) Fit the MR-16 into place and press firmly for 15 seconds. Let stand 12 to 24 hours.
6) Separate a section of SPT wire at the end and strip off 1/4" of insulation.
7) Attach the Molex sockets to the SPT wire. I soldered them but crimping is ok. Note: Thanks to Annalisa for the Molex tip.
8) Feed the other end of the SPT wire through the "bottom" hole. Attach the Molex sockets to the MR-16 pins.
9) Apply Teflon tape to the cleanout plug and then screw it into the back of the PVC adapter. You have finished the project.
10) Optional - paint them with plastic paint.
The Action MR-16s I used turn out to be waterproof from the lens side, so this design works well. The back wiring side is protected by the PVC. The wire exit also provides a path for any stray moisture/condensation to run out (I don't recommend sealing it).
Note: The 1 1/2" sizing is because PVC is measured by inner diameter. The adapter has a ~1.85" wide opening to accept the 1.5" ID PVC. That opening works about perfectly with the rim of the 2" MR-16 bulb.
Everything is parallel; no resistor is required, just 13.8VDC. Polarity doesn't even need to be observed as they do internally contain a full wave bridge rectifier.
As a side note these can be wired 10 in series and used on an AC controller... I did it last year and it works well. I opted for DC this year instead for other reasons.
Yes, they can dim... however it isn't perfectly linear (typical of LEDs).
The house siding is vinyl in a basic tan like color.
You'll notice that I had to use twice the number of red than green or blue... they are dimmer than the green/blue ones. The blue is very vivid, as is magenta (red + blue at the same time). White (red + green + blue) is almost blinding... great for those moments when you want the added punch.
I have not tried the suggestion of a
series resistor with the Action MR-16s. In theory it might linearize the gamma
curve some, however these effects will need to be observed:
As the resistor size increases (in ohms) the linearity will increase (to a point of diminishing returns anyway). However, increasing the resistor size will also increase the voltage drop which will need to be compensated for at the power supply and will also require a higher wattage resistor.
Ohms law can be used to calculate this, or for the practical appraoch (recommended due to the linearity quirks of LEDs) one can do the following:
Place a multimeter (set to read mA) in series with the MR-16 and attach it to the power supply at the rated DC voltage (for the Action floods this is 13.8V) without using the series resistor. Note the current draw. Now wire the resistor and multimeter and the MR-16 in series and repeat the process. The mA reading will be lower. Dial up the supply voltage slowly until the multimeter reads the original current value in mA. This is the new required supply voltage.
The difference between the two is the voltage drop across the resistor. This can be multiplied by the current value to determine the required minimum resistor wattage rating. For example, a 6.8 ohm resistor might drop 1.25V and require 1.25 * 0.167 = 0.21W (1/4 watt would work, but 1/2W should be used to be safe... always err to the next size up) and a supply voltage of 15V. If running long lengths of wire you may also want to take the wire resistance into account.
I use a BK Precision 1692 bench supply (rated to 40A continuous) to drive all of my floods. There are far less expensive solutions but I thought I'd share what I've been using.
The Action MR-16s should not be run at 12VDC... they are only 50% bright at 12V as opposed to 13.8V.
Each MR16 will draw .167 amps so you'll need an appropriately sized power supply. If you are using an LOR or D-Light DC controller you will need to use a DC power supply of sufficient size. For example if your DC power supply can output 12 volt DC at 10 amps, you will be able to power 60 MR16's (10 amps / .167 = 59.9). See my DC Controller page here.
If you just want to power the MR16's on without dimming or animation control then you can use an AC landscaping transformer.
You can even wire up 10 MR16's in series (without resisters) and power them right from a 120 volt ac animation controller. I have not done this personally but some have successfully.