Jump to content
Light-O-Rama Forums

RGB Color Changing LED Rope Light setup - how to divide up


rickharp

Recommended Posts

this year, i'd like to replace my gutter ice cicle lights with a three color RGB Color Changing LED Rope Light and install on my eave, so the rope light is actually hidden but it lights up the facade or front of the house. sounds cool, and i've got to make sure it will be bright enough, but, here is my concern.

besides the costs....

everyone i've asked and what i've researched indicates that the strand can come with a

[*]3 5' Power Cord with Power Connector (Includes inline rectifier)
[*]1 Multi Function Inline Controller (Runs up to 200')
but, i am curious if anyone has figured out or can let me know how i can hack the controller to allow the 3 input 110 sources coming from the lol. i suppose there is some sort of inline rectifier for each circuit. can i assume i can install a rectifier inline and hard wire each strand, and use the shared common.

Birddog looks like the best source so far.
http://www.birddogdistributing.com/color-changing-rope-light-controller-p-766.html

anyone have any other thoughts.

Thanks

Link to comment
Share on other sites

it appears that the ropelight is 120v over each circuit. The 39" cut length confirms this - 3.07v per led at 1" spacing = 120v at 39" The rectifier smooths out the flicker of the ac source (as the leds are biased they would be on only when the source is poitively biased and off when negatively biased - this flip flop happens 60times per sec)

to get a smooth output you would need to install a capacitor on the output of the rectifier. It is possible to not use a cap, but there will be a slight flicker as the power curve would look like a series of bumps compared to a sine wave of ac and a straight line of dc.

a shorter answer - yes it is possible, though I don't know if it would be stable dimming.

Link to comment
Share on other sites

Thanks for the reply.

would the 39" secton i have in my hand be to short to test this with a lor. would the results be the same if it was about 120 feet.

so you think i could hack the plug or the end cap to provide power to each lead (3) but add a capacitor and a rectifier to each lead. any info on what kind or size capacitor or rectifier i should get. would it differ based on lenth of rope.

Link to comment
Share on other sites

the 39" section would be fine to test with

all the other sections are in parallel to each other (i would rather kill 39" than 120')

the rectifier needs to be a 600v rated for at least the amperage of the overal length

the cap - is one you migh need to play with - and explode a couple

Link to comment
Share on other sites

the 39" portion came with a inline rectifier buried in a ton of plasitc. i cut and chipped at it to find out it was a KBL608, which is raated for 800 volts.

http://www.datasheetarchive.com/pdf/1884617.pdf

i removed the rectifier and sent 110 into one color and the common, and it seemed to work fine. i was curious though, will the led's be dimmer if there is 120 feet of lights compared to 39".

I suspect i'll ahve to get 3 rectifiers and dup what they did, but do it for each channel.

consumes 0.8 watts per foot, so 96 watts per channel if i use 120 feet...

Link to comment
Share on other sites

If each parallel string of LED's has it's own current limiting resistor, and you forgo the filter capacitor after the full wave rectifier, why would this not be dimmable?

Most full wave LED strings that I am aware of only use the rectifier, and the current limiting resistor, and they dim quite well.

- Kevin

Link to comment
Share on other sites

Dr. Jones wrote:

yes kevin

you should be able to dim them, although the curve will be fairly steep

I can confirm that the dimming curve is pretty steep using just the full-wave rectifier. I have run a single colour LED rope for a couple of years now using just a small rectifier within one of my LOR enclosures.

Martin
Link to comment
Share on other sites

rickharp wrote:

i was curious though, will the led's be dimmer if there is 120 feet of lights compared to 39".


Dr. Jones wrote:
the leds should not be dimmer as each section is wired in parallel


Sorry, I missed the context the first time around. Correct, any differences should be more theoretical than visual. One segment may not draw enough current for the full rectifier voltage drop to occur, so with multiple segments you may loose a fraction of a volt more to the rectifier. Also not sure what gauge the wires in the rope light are, but especially if all colors are on, you will have a couple of amps in the common, and may have measurable voltage drop along the 120 foot length, which may result in the far end being a bit dimmer, but I don't expect it to be enough to be a visible difference.

- Kevin
Link to comment
Share on other sites

The steepness of the dimming curve of an LED string depends on the number of LEDs in series. A 35-bulb string will have a very steep dimming curve, while a 25-bulb string will have a less steep curve, and thus will be able to be dimmed easier.

The reason is that the voltage drop across 25 bulbs is less, so it will light during a higher portion of the AC waveform, giving more room to dim.

The trade off is that both the 25-bulb string and the 35-bulb string draw the same amount of current, which means they both take the same amount of power. The excess power in the 25-bulb string is dissipated in the resistor. (Actually, the 35-bulb string may draw a bit more current since the bulbs are probably driven harder.)

A 50-bulb string is really two 25-bulb strings in parallel, so will dim just like a 25-bulb string.

Link to comment
Share on other sites

A 50-bulb string is really two 25-bulb strings in parallel, so will dim just like a 25-bulb string.



Do you mean a 100 bulb is two 50's?
Link to comment
Share on other sites

Dr. Jones wrote:

A 50-bulb string is really two 25-bulb strings in parallel, so will dim just like a 25-bulb string.

Do you mean a 100 bulb is two 50's?

It actually depends on the color. Green, blue and white LEDs take about 3 volts, so 50 white LEDs in series would require more than 150 volts. Therefore a 100-bulb string of white LED lamps is actually four 25-bulb strings in parallel.

I suppose you could find a red, orange, and yellow string that is 50 in series, since those bulbs only need about 2 volts, but I'll bet that isn't that common.
Link to comment
Share on other sites

gotcha

I took a look at my old set of leds (a 50 string) and it has 4 wires. -2 x25 strands makes sense

Link to comment
Share on other sites

looks like the same LED ropelight that is available through CB Concept Studio on Ebay.



I ran into this a couple of years ago. The LED RGB rope light is "positive grounded" or common positive, not common negative. I tried a few different ways to control this LED rope light with an LOR controller outputting AC and feeding it through a full wave bridge for each channel, it didn't work.

Link to comment
Share on other sites

in most cases they include a $25 controller to make the lights chase and dance. in order to chase and dance, i could see the need to have two commons and alternate them. If you look through the rope, there are lots of resistors and crossovers. boy, i'd love to find a way to make this work. the 3/8 x 3/4" rope light would be so easy to install, store and setup compared to three rope lights.

Has anyone else had any experience with this. since each working section is 39" long, i guess i could get three sections, or 10 feet of it and experiement with a lor controller.

if the rgb strand would work, i bet it would be popular for lor'rs.

would love to hear more on this topic. thanks for the input.

http://www.birddogdistributing.com/color-changing-rope-light-controller-p-766.html





[*]Brand New
[*]164' Roll with Accessory Pack
[*]110/120 Volt (No transformer required)
[*]Color: Red, Green, and Blue LEDs
[*]Rope Shape: Flat - 3/8"x 3/4"
[*]8 Function In-line Controller Included
[*]Effects: Steady On, Chasing, Slow Fading, Slo-Glo, Flashing, Wave, and Sequential (Shown in animation)
[*]Extended life of 100,000 hrs
[*]Brightness: 3500 mcd (Millicandela)
[*]Energy efficient--only consumes 1.5 watts per foot
[*]SJT (Heavy Duty) Power cord with rectifier & 2-prong polarized plug
[*]Indoor/Outdoor
[*]Vertical Bulb Placement
[*]1" bulb spacing
[*]Cuttable in 39" lengths
[*]Max operating length is 600'
[*]Dimmable
[*]3 5' Power Cord with Power Connector (Includes inline rectifier)
[*]1 Multi Function Inline Controller (Runs up to 200')
[*]2 Y-Connectors
[*]5 Inline Splices
[*]2 Female to Female Extension
[*]10 End Caps
[*]50 x Mounting Clips

Attached files 154221=8906-led-rgb-cut-end-small.jpg

Link to comment
Share on other sites

It would work if LOR had a high voltage DC (positive common for chinese lights) 16 channel board available for 120 VDC LED rope lights. The boards are currently for AC current. The current DC board is only rated up to 60 volts DC. A standard LOR board may work but your LED ropelights will have the "flickering" problem.

Here is what I did, this gets into DMX.
http://lightorama.mywowbb.com/forum75/16160.html

Link to comment
Share on other sites

Thanks Lonewolf

All i currently have to test with is a 39" section, and my testing with the lor controller, faired perfectly, and i have not used a rectifier or bridge, just straight 110v ac. dimming, twinkle, all works fine.
So I am somewhat confident it will work fine. In you r picture the rgb rope light looks quite similar to mine (see pic above). I plan to test it with a 9.75' section to see if there is any problems with the shared common.

if anyone else has any first hand experience with this please post. thanks

Link to comment
Share on other sites

  • 4 weeks later...

i've tried a 7 foot section with a LOR, twinkel, fades, all work fine. i am convinced this works great without a rectifier. i am unable to distinguish a rapid pulsing, and think that i'll go wihtout adding recifiers to each channel.

If you believe this to not be wise, i'd love to hear from you. thanks for the input.

Rick

Link to comment
Share on other sites

  • 2 weeks later...

I may have found the controller that I have been looking for. I have ordered it and waiting for it's arrival. I will post on how well it works and where to find them. LW

Link to comment
Share on other sites

Guest
This topic is now closed to further replies.
×
×
  • Create New...