CMB-24d outlining the house and windows

[rednosetbird]

Hi All, not to sure if this is going to work! I made a crude drawing of my house and what I would like to do. The question I have is will this all work out? I have all Light-O-Rama power supply's and RGB strips. So... will this work out. I have been trying to research every thing but cant fine a answer. Can I run a 20'-5" ribbon continuously or do I need to brake it up into two 10'-2 1/2" strips and feed from the middle with a "y" connector or do I need to run two wires of 4 from the CMB-24D from one channel and feed the two lengths? OMG!!! I hope I am not over doing this! I know there is a lot to consider with voltage drop with smart pixels,  do I need to worry as much with the dumb RGB? I think the longest run I will have from the CMB-24D to a strip is 28'. Please advise!!! Not sure if more info is needed!

 

Thanks, Bill

[asl9622]

I am in the same boat as you. I did a show last year with the standard mini lights. I found this thread which helped me out a bit. I think running wires parallel is your answer. Good luck! I am starting my planning now.

 

http://forums.lightorama.com/index.php?/topic/31815-how-to-inject-power/

[k6ccc]

A couple of points.  First, you have some strip cutting and splicing in your future.  Not a really big issue, but you need to be able to solder and waterproof. 

 

You most likely COULD get away with feeding 20 feet of dumb strip from one end, but if it were me, I would feed the strip from both ends, or the middle, or whatever worked out for the particular longer strip.  the general rule of thumb is to not feed more than one full length strip a single end.  The biggest issue is the ability of the traces on the strip to carry current.  They really are only large enough to carry the current for themselves.  Dumb strips are not quite a picky as smart pixels, but there are still limits.

 

If it were me, I would run a larger power supply than the 200 watt supplies you have listed.  If you turn all of your strips on full white at the same time, you WILL be overloading the power supply.  I would get one of the commonly available 350 watt supplies for each card rather than the 200 watt power supply.  I don't like running power supplies hard up against their limits.  Granted, that in most cases you won't have all of the channels full on at the same time, but it is something to keep in mind.

[jerrymac]

Can't power inject Dumb Strips,  If you have long runs you need to use a extender or another controller w/power.  Unlike smart strings that use power  ( pos and neg), data and on some types clock.  Dumb strips use a positive for each of the three colors and a single ground (might have this backwards) the controller just closes the connection to each color as required.  As such you do not have any where to inject power.

Might be easier to use smart strips ( and just a cheap now),  if you want less channels then just group them. This way you only need power and ground as well as data to the first (maybe the middle of the setup) and Power and ground to every 15 feet or so with a single data going between strips or strings). Availability for pixel to pixel chases or groups of as many or few as you want.  Current E1.31 controller now handle hundreds of pixels each.

[k6ccc]

Wrong Jerry. You absolutely can inject power on a long dumb strip without an extender. It is done differently on dumb strips than smart strips, but completely possible.

There are dumb strips that have a common positive and other strips that are common negative, however for our purposes, we use strips with common positive. The controller is controlling the negative.

For dumb strips you need to bring all four wires to the inject point. It can be at the two ends, somewhere in the middle, or where ever works for the installation. In my landscape lighting I have three strips that are fed from both ends. They are each on the inside of a brick ring around trees so both ends of the strip are within a few inches of each other. There is a cable coming off each end of the strip which join together and then go to the controller. The only real issue is total current for each channel. In general terms, a 5 meter long 30 LED per meter RGB strip uses about 1 amp per color. The LOR DC controllers are rated (if I remember right) at 4 amps per channel, so feeding two strips from one channel trio is just fine...

[EmmienLightFan]

Can't you just connect another positive from the same supply? Or get an amplifier?

[k6ccc]

No

 

Can't you just connect another positive from the same supply? Or get an amplifier?

 

No.  You really need to connect all four wires.  Yes, the common positive is likely more picky because it has the current for all three colors, rather than the wires for the colors that only have the current for a single color.  I have never looked at a strip to see if the common plus trace on the strip is larger than the trace for the individual colors. 

 

As for an amplifier for RGB dumb strips, I have seen listings for them on-line, but never seen one.  I have never had a need for one so never done anything about them.  Should work if you really need that much strip lit up the same.  However a single set of outputs from a LOR DC card can handle the current for several full strips.

[mpageler]

30 leds/meter are rated at 36w full power and 60 leds/meter are at 72w.

So running continuous 20ft of 30leds/m is not and issue. IMO, no use makeing wiring more complicated than needed.

In other threads, seems like the general feeling, the 30 led/m are more than adequate.

[Little_b]

Hey Bill-

I ran into some of the same issues as you when I first put up my Dumb Strips.  Most of my runs are roughly 20-25ft long, with one being 50'.  I originally bought some amplifiers to use but decided it was more work than it needed to be.  What I did to avoid dealing with voltage drop and running extra wire and power supplies, was to run one wire to the middle of each run.  Now I did not cut and put it exactly in the middle, just hung the 16.4ft and the 5-6ft sections and ran the power to the point where they meet.  I haven't seen any real issues with power drop or color difference between the longer and shorter runs.  

 

I agree with k6ccc about the power supply, go with the 350 Watt, this way you have room for expansion in the future, after all lets face it, we're never "really" ever done.

[rednosetbird]

I think if I am understanding this correct. What I can do for my situation for the long runs, for example my 20'-5" run split it in half and feed it with two leads from the CMB-24 from the same channels so I don't have to worry about voltage drop.

 

One more thing for my "14' and 14' run will = 28'  If I am understanding everything correct I will be able to run that length.????  I am lost with this. Little_b said his longest length is 50 feet, is that the length of the strip or how far its from the CMB-24?  Can just split it just like above?

[k6ccc]

Rednosetbird,

Here is the easiest way to think about it.  What is the longest distance from the power feed point to the any LED.  If that distance is no more than the length of a full strip (normally 5 meters - or just over 16 feet), you are just fine.  It does not really matter where the feed point is.  For example, using your 28 foot strip, if you feed it at the middle, the longest distance is from the middle to the ends (in this case 14 feet), so you would be fine.  You could also feed from both ends in which case the middle would be 14 feet from the feed, so again you would be fine.  The wrong way to do that would be to connect the two strips to make a 28 foot long strip and feed it from one end.  That would mean that it would be 28 feet from the feed point to the last LED.

 

Reference your last line, yes you could run a 50 foot strip, but you would have to feed it in several places.  For example, assuming the 50 strip is actually three 5 meter strips, you could feed power at the start of the first strip, and between strips 2 & 3.  You could also feed it at the joint between strips 1 & 2 and also between strips 2 & 3.  Another option would be to feed at both ends and also one of the joints.  You can really feed wherever it is convenient as long as you don't exceed 5 meters from feed point to any LED.

 

BTW, especially with dumb strips, you likely can get away with a little over the 5 meter length, but it's a good target to use.  In my case my longest dumb strip in my year round landscape lighting is 6 meters.  Because it was convenient, I am feeding the strip at both ends.  I am doing the same things on the other two tree rings which are using a singe 5 meter strip.  See the last photo at:

http://newburghlights.org/Landscaping.html

to see what I did.

 

If you are running really long strips, you will have to give though as to the current capacity of the controller card.  According to the specs for the CMB16D (which is what I have), each channel can supply 4 amps without heat sinks (1 and 1/5 amps for first generation boards) or 8 amps with heat sinks.  The total for each bank of the board is 20 amps and 40 for the entire board.  For the CMB24D, the channel limits are the same (except for the the first generation limit mentioned in the CMB16D), but the board limits goes up to 30 and 60 amps for the banks and entire board.

 

The current limitation is particularly an issue if you are running long strips of 60 LEDs per meter as those are about 2 amps per channel so any more than two strips would require heat sinks and I would not want to go much past three strips of 60 LEDs per meter on one channel trio.  If you really needed that long of strips, I would be splitting it into separate channel trios.

[asl9622]

Thanks for the great information. I am outlining my roof and know I will have some decent runs of cable. My biggest concern is overloading the thing. Just to make sure I have it right, the CMB24D has 24 channels but when divided by RGB you are given 8 channels of any color. White uses each red, green and blue thus pulling the biggest wattage and amperage. The 24 channels can each handle 4 amps per the description so each RGB channel can handle up to 12 amps correct? With a 5050 150/m 5 meter dumb strip using 3 to 4 amps, then I could technically run 3 strips safely without overloading a channel. My only concern then would be to make sure the power source can handle the wattage correct? Please all you experienced light show folks correct me. My biggest concern is safety and not burning out expensive equipment. I will be measuring the runs tomorrow so I can do my calculations. So far I am looking at 3 CMB24D's with maybe a need for a fourth to do the roof and house outline, windows etc.

[EmmienLightFan]

I RGB amplifiers are great. Last year, when I didn't have my LOR stuff controlling RGB, I had an RGB controller that reacted to sound. It was OK, and had some nice effects, but I will just use it for testing now. Anyway, in the manual it said about amplifiers when connecting more than 2 strips. (I only had two strips connected, and I shouldn't even have done that with my 5amp power supply, as I measured 7amps being pulled.) I looked at them online and they are really useful. If you have a long run, put one at the end in a waterproof pattress box and it will boost the signal. They have a limit to how small the signal will get before it can't boost it, but it's quite small. If you have just one really long run, they are really handy.

[Little_b]

Sorry for the confusion with 50'.  The strip lights are 50' long. I connected the power at 2 points. 

 

-----------P-----------P------- (p=power point). 

    16.4'      16.4'      16'    

 

The shorter length's are as such:

 

-----------P-----

   16.4'      5'

 

The  longest distance between the controller and Light Strips is about 40'.

 

Hopefully this clarified things.

[rednosetbird]

Now I one more question. With that  50' length if you have it on at 100% all 3 channels to make white, is the Cmb-24 going to handle that?

[Little_b]

I am using 30LEDs per meter strips so the power is less than the 60LEDs per meter.  I haven't had any issues so far, that being said, I don't normally run that section for long periods of time, nor do I use the white very often.  I have 2 50' sections, one on top of the roof and another along the rain gutter.  I straddle my deer and sleigh over the one on the top of the roof and so I use them when using the color white.  The section along the rain gutter I broke into three sections so during July I can have Red, White, and Blue colors.

 

********Before I ever hung or mounted anything, I got out my Multimeter and measured the actual power, amps, and volts used on each strip, as well as the power used when combining strips.  The specs say what they are supposed to use, but I have yet to see the same in the actual usage.******  This is the key to making sure you don't fry your board.

[rednosetbird]

Thanks to all, I am ready now to start wiring everything now. I cant wait to see everything all lit up!

 

Thanks again, Bill

[drivemewilder]

Hey everyone, so last night I did an all-white test on my 4 windows and 1 door.  Using the CMB24 and bullet pixels from Ray and a 350W power supply.  Because of location, I chose to put the controller setup in the corner at the end of the front porch.  To the door was about 3' with about 3' spacing between the windows as well.  With the windows being about 2' wide and the 3' spacing, it's roughly 25' from controller to last window. Sure enough, the last window was actually purple instead of white.  So I need to consider injecting power to the last string (I didn't count but a guesstimate would be 50 lights on each window).  But from reading it also sounds like I could place the controller in the center, bringing the power supply closer to all the windows and that would solve my power problem.  Is that accurate?

[Mr. P]

I have 16 windows on the front of my house and I use two CMB24D for those windows. My closest window to the controllers is about 6 feet and furthest two windows are 70-80 feet away and I don't have any issue. I use strips instead of strings and I have to use one and a half strips per window as my windows are almost 8 feet tall. I turned up the power supply to 12.8v to make up for some of the long runs and I use nothing smaller then 18 gauge wires for my extensions and so far I am good.

[drivemewilder]

Well that's good...but doesn't answer my question!  I'm not buying a second CMB24 and power supply to outline 4 windows and a door.  I already have a brand new CMB24 and brand new bullet pixels, so I have to find a way to make them work.  If it means changing the intensity of the white on the few occasions I have white, I will.  I can't say for certain, but I'm pretty sure the wiring is 20 gauge on the strings.  Although I think it's 18 gauge on the spool of extension wire I'm using to go from controller to windows.  I definitely did not have white on the last window when it should've been, so there is a problem somehow.  I also check each string individually, each color before and after I put the pigtails on to ensure everything has a good connection.