Step 6 : SSR Cont'd


Again I apologize for the quality of the photo. The SSR control box has no heat sinking. My lighting display typically has 11,000 to 12,000 miniature lamps, but only a fraction of the animated lights are on at any one time. Typically, a whole control box of ten channels has only 4 or 5 strings of 100 lamps on at once. The triacs are rated at 4 amps. The whole box of 10 channels is fused at 4 amps with a fast acting fuse. You will have to determine whether the triacs need heat sinking and more ventilation in your situation and make modifications. Also be aware that the metal tabs or bodies of non-isolated triacs are at 120 volts. 120 volt power is available at numerous points in the box.

There is a partition between the receptacle side and the electronic control side. The circuit board is on standoffs. The 120 volt bus is a 12 gauge copper wire held off the board by Vector(T42) push in terminals. The 12 gauge wire is used to provide substantial construction, not for the current rating of 12 gauge wire. The data lines come in from one end of the box and go around the back for connection to the optoisolators. The power comes in the other end to the 120 volt bus and out to the receptacles from the triacs. It is very important that none of the wiring come loose from connections. The circuit board is a perf board with copper pads around each hole. I used a bare copper tinned wire to solder traces to the back of the perf board for the low current traces. I use the unconnected copper pads as needed to solder the traces in place. Of course you can make a printed circuit board. From the schematic diagram shown at the beginning of the How To you should be able to complete the control box. If this is not enough information, it is a good sign that you should not proceed without qualified help.

Step 7 : A Project


A project is needed to demonstrate the use of the basic circuit. It is the tree shown at the beginning of this How To. The tree appears to have rotating lights.

The main support is a piece of wooden handrail about 8' long purchased from a home improvement store. It is painted black. A star with 35 blue lights is placed at the top of the pole. Holes for the lamps were drilled about ¾ inch in from the perimeter of the star. Slots were cut from the perimeter into each hole for wire clearance. Lamp bases are pressed into the holes for a friction fit. A bolt and nuts were used to stand the star off the pole about 1 inch. A 6 inch disc made of 3/4" plywood was added below the star. Holes were drilled at 18 degree intervals around the perimeter of the disc. Pieces of bare #12 copper wire were used to form a hook for each hole.

Step 8 : Lower Lighting Support


The lower lighting support is a piece of plywood 4 feet in diameter. Areas were cut out to leave 4 spokes to make the assembly lighter. Braces were added as shown to screw the lower support to the pole. Holes were drilled around the perimeter of the lower support at 18 degree intervals. The lower support was fastened to the pole about 18 inches from the bottom of the pole. A support made of 1/4" plywood is used at the approximate vertical center of the tree for additional support of the lighting supports. Adjust the diameter for the location. The lighting strips rest against this support but are not fastened to it. I fastened it in place with a small metal angle. The lower and middle supports are painted black.

Step 9 : Lighting Strips


The lighting strips are about 82 inches long. I used two 50 lamp strings (one red, one green) for each two strips. The strings run up one side, over the top of the tree and down the opposite side. I spaced the lamps farther apart at the top half of the tree, since adjacent lamps are closer together at the top. The length and spacing of the lamps could be affected by the strings of lights used. The lamp spacing of the strings must be far enough apart to be spread out along the lighting strips or the size of the tree must be adjusted. The strips are painted white.

The strips are made by cutting slots or dadoes about half way through 1/2" x 1/2" wood strips. The depth may have to be adjusted to fit your lamp holders. The slots may be cut in a 1/2" thick board and then ripped into ½” wide strips. Two strips are nailed together with the slots facing each other. This forms an opening to hold one red and one green lamp at each slot. Note: Two lamps at the upper ends of the strips are not placed in slots. This provides the clearance needed to allow connection of the strips at the top of the tree. An eye screw is placed in the upper ends of each set of lighting strips. One side of each strip has an angled cut to provide clearance at the top of the tree. Each pair of strips is hooked over the hooks at the top of the tree so that they are on opposite sides of the tree. It can be a little tricky getting the last few strips in place. Some of the wiring and lamps between each pair of strips can go over the top of the disc at the top of the tree and others can be slid under the strips already in place and be below the disk. Number 20 or 22 gauge wire is then run through the hole in the lower support and around each strip to hold it in place. The wire does not need to be too tight.

Step 10 : Additional Notes and Comments

Dimensions are not too critical. I suggest you make a scale drawing to make sure the tree has the profile you desire. One thing to watch is the diameter of the disk at the top. You need to make sure there is enough clearance around the perimeter to hook the 20 lighting strips in place. A 2 inch angle iron was driven into the ground to hold the tree. The pole bottom is held a few inches above the ground and fastened to the angle iron with pipe clamps. I have never had a problem with wind blowing the tree over, but you may want some guy wires.

This tree has evolved over the last 15 or 20 years. Each group of red strings located 90 degrees apart is connected together. The green strings are connected in the same way. There are 5 groups of red lights and 5 groups of green lights. Adjacent strings are plugged into the SSR box sequentially. Two timers and decade counters are used. The decade counters each count to 5. The red and green strings are connected so that they appear to rotate in opposite directions. The red lamps are sequenced at a fairly high rate. The green lamps run at a slower rate. Four strings of 140 continuous running chaser lights were also used. One string is taped up and down the pole at the center of the tree before the strips are attached. The lighting strips extend below the lower lighting support. Holes have also been drilled in the bottom end of each strip. A string of 140 chaser lights is run around the tree at the bottom of the strips and is held in place with light wire through the holes. Two other strings of 140 chaser lights are spiral wound 180 degrees apart from the top to the bottom of the tree. The star at the top is lighted continuously. The total light count for the tree is about 1,600.

I have received many compliments on this project. The lights change appearance as you approach the tree and may appear to change directions. I don’t know why. I also don’t know if you will get the same results. You can experiment endlessly. You can try other configurations of lights.The most unusual thing that happened was when a police car pulled into my drive. A policewoman came to the door. I was expecting really bad news. She said "That tree is the coolest thing I have ever seen!" She wanted to know where she could buy one.