1. New to Christmas lighting? Get started with the AusChristmasLighting 101 Manual:
    auschristmaslighting.com/wiki/AusChristmasLighting-101

Powering pixels

Discussion in 'RGB Lights - Intelligent Pixels and 3-Channel RGB' started by BundyRoy, Jun 10, 2014.

  1. BundyRoy

    BundyRoy Dedicated Elf

    Joined:
    Apr 9, 2014
    Messages:
    1,026
    Likes Received:
    9
    Hooked up some lights on the weekend. Only mucking around with the test mode to test my strips and see what I could run.Discovered a few surprises that either surprised me or I can't explain.

    I have a 10m strip light that I have now determined is 2811. It is 30 LED/m and 3 LED/pixel. So there are 300 LED in the strip and 100 pixels. It is currently powered by a laptop style power supply that came with it. 12V 6A output. This power supply ran 2 of these 10m strips last year when I had it up. Anyway I used the same power supply for testing (power injecting) with one 10m strip and hooked the data and negative wires to the pixlite 16 for control. I hooked up the power before I hooked up the data and I didn't realise/check it but the power was on. All the lights came on. Can't remember the colour now. Then I hooked up the data cable and all lights went off as there was no signal being sent at the time.

    Is it normal for the lights to come on if there is no data signal. Could this do damage. I'm not planning on doing it again.

    Next I had some 3m strips of INK1003. 30 LED/m and 30 Pixel/m. So 90 LED and 90 pixel per strip. Had these hooked directly to and powered through the pixlite 16 for testing. 1 strip ran fine. 2 strips connected together ran fine. 3 strips connected together ran but started to get pink and flickering about 1/3 the way into the 3rd strip when on white. I assume this means too much voltage drop.

    Now I have 1 strip (10m) with 300 LED power injected at start that works fine and 1 strip with 270 LED powered through controller that doesn't light up properly. Do you think that if I power inject the INK1003 I will be able to run the 3 strips. Or is it something to do with the fact strip that works has 100 pixels and the one that didn't had 270 pixels.

    I hope this makes sense. In my final set up I plan to power the ink1003 downstream of the controller anyway. Just want to know what my chances are of running 3 strips so I can work out the number of outputs I need to allocate.
     
  2. fasteddy

    fasteddy I have C.L.A.P Global Moderator Generous Elf

    Joined:
    Apr 26, 2010
    Messages:
    6,497
    Likes Received:
    22
    Location:
    Albion Park NSW
    Find Me On:
    1st, connecting up power and data to lights when powered on is not a good practice as this can damage the first pixel. The reason you had all lights on was because of the data being spiked when the power was connected. The reason they went off when the data was connected was because the data stream would have been sending an off signal

    Now the other issue you are discussing is to do with voltage drop. If you connect more than 1 strip together (more than 5 metres) and you are not seeing issues on the second strip then thats because you most probably are testing straight from the controller and without an extension cable which if in place will also effect your voltage drop. If using 12vdc strip the amount of voltage drop is less to contend with compared to that of 5vdc
    So the basic rule is if running 3 strips you will need to at least inject between strip 2 and 3 so you back inject down strip 2 and up inject up strip 3
    If using 2 strips then in most cases you will still need to inject at the end of the second strip

    In most cases you can mix and match the strip, modules and pixels as long as they are using the same IC or very similar, there are some slight variations with chips that can cause some issues when running together.

    As far as running the ink which uses a 2812b chip connected to a 12vdc 2811 chip then there may be issues as there are some slight variations in the chips. Its a case of try and see if it works
     
  3. OP
    OP
    BundyRoy

    BundyRoy Dedicated Elf

    Joined:
    Apr 9, 2014
    Messages:
    1,026
    Likes Received:
    9
    Thanks Eddy, got some good pointers about back injecting there. Hadn't really thought about that.

    Still not sure though how one strip with 300 LED worked and one strip with 270 LED didn't. My guess is it's the pixels using the power not the individual LED. As the 300 LED strip is 100 pixels and the 270 LED strip is 270 pixels. Sorry if my terminology is all wrong here but I hope I got the point I was trying to make across.
     
  4. fasteddy

    fasteddy I have C.L.A.P Global Moderator Generous Elf

    Joined:
    Apr 26, 2010
    Messages:
    6,497
    Likes Received:
    22
    Location:
    Albion Park NSW
    Find Me On:
    Without an actual link to the strip you are talking about then its all assumptions

    The ink can be a 5 volt or a 12volt strip depending on which supply wire you connect, so if you connected 12vdc to the 5vdc wire then you most probably damaged the strip

    Also the fact that there are some variations with the 2811 and the 2812b chip used in the different strips then this may also be causing you issues.
     
  5. OP
    OP
    BundyRoy

    BundyRoy Dedicated Elf

    Joined:
    Apr 9, 2014
    Messages:
    1,026
    Likes Received:
    9
    No the strips all fine. They are two different types of strip.

    The first strip is 2811 protocol. It is one piece 10m long and has 300 LED which form 100 pixels (3 LEDs/pixel). I can run this off 12V fine. All LEDs work fine on white.

    The second strip is INK1003 protocol. Running on 12V (and hooked up correctly to 12V tab on strip). I have 3 by 3m pieces joined together. This makes 270 LEDs and 270 Pixels. 1 LED/pixel. This doesn't work properly hooked straight up to the controller. The last 60 or so pixels are pink and flickering when strip is on white. All other colours work fine.

    I only ever ran one of them hooked up. So both are 10m long (allowing for pigtails in the 3 strips joined together). One has 300 LED operating and the other 270. The one with less LEDs is the one with more voltage drop issues.

    My logic says that the more LEDs there are the more power should be used. This doesn't seem to be the case in this scenario. I'm assuming it comes back to power use/pixel not power use/LED. Or maybe it is due to the INK1003 being less efficient as it converts from 12v back to 5v to run the LEDs. They are the only things I can think of but that's not to say they are the only options.
     
  6. fasteddy

    fasteddy I have C.L.A.P Global Moderator Generous Elf

    Joined:
    Apr 26, 2010
    Messages:
    6,497
    Likes Received:
    22
    Location:
    Albion Park NSW
    Find Me On:
    This is caused by the differences in the strip used

    The strip with 3 LEDs in series will draw 1/3 of the power of a strip with the same amount of LEDs that has individual control.

    So 3 LEDs in series will draw the same current as 2 LEDs in series or just 1 LED as LEDs are current driven devices.
    The rules with LEDs is

    Series = add voltage together
    parralell = add current together

    So the ink will be drawing a lot more current than your 3 LED per pixel strip and this is where your issues lie as these are very different strips as far as the LED arrangenment goes.
     
  7. OP
    OP
    BundyRoy

    BundyRoy Dedicated Elf

    Joined:
    Apr 9, 2014
    Messages:
    1,026
    Likes Received:
    9
    Thanks Eddy, that makes sense.
     
  8. OP
    OP
    BundyRoy

    BundyRoy Dedicated Elf

    Joined:
    Apr 9, 2014
    Messages:
    1,026
    Likes Received:
    9
    Next question about lights and data signal.

    I have been working on the premise that I can only send the data around 5m without putting in a null pixel. I have made up two lengths of 14/0.2 cable to transfer the data from the controller to the INK1003 strip.

    Did a test tonight with the two lengths joined together to make 10m between controller and first pixel with no null pixel. The lights are not powered through this cable. The lights came on with the test pattern fine. I am using a pixlite 16. There was no flickering or any indication the data strength was not good enough. Only had one output going though with 90 pixels hanging off it.

    Was wondering if this means it is okay to run like this or will the performance deteriorate once I have more than one strip attached to the controller or more complex signals passing through the cable.
     
  9. Kaden

    Kaden Pixels! I need more pixels!

    Joined:
    Jan 10, 2012
    Messages:
    724
    Likes Received:
    0
    Location:
    Gold Coast
    Possibly it will be fine but I think that distance is out of spec for WS2811 so I wouldn't run my show like that. However if it works for you and you are happy to risk corrupted data, it is not going to hurt your pixels .
     
  10. fasteddy

    fasteddy I have C.L.A.P Global Moderator Generous Elf

    Joined:
    Apr 26, 2010
    Messages:
    6,497
    Likes Received:
    22
    Location:
    Albion Park NSW
    Find Me On:
    In my experience what works on the bench may not actually work correctly when all connected with all the other lights and power supplies creating interferance. You may see a good stable signal on the bench but may get flickering when all connected and running.\

    But if it works on the bench now then see how it goes when all set up and running, if you then see issues then just add a dummy pixel.
     
  11. OP
    OP
    BundyRoy

    BundyRoy Dedicated Elf

    Joined:
    Apr 9, 2014
    Messages:
    1,026
    Likes Received:
    9
    Thanks for the replies. I figured it would be too good to be true. I will give it a go set up as a test but will put in a null pixel for the show. Like you say why take the risk.
     
  12. OP
    OP
    BundyRoy

    BundyRoy Dedicated Elf

    Joined:
    Apr 9, 2014
    Messages:
    1,026
    Likes Received:
    9
    This got me thinking. Is there specs for each of the chip protocols available online anywhere. I know most of it won't mean anything to me but I might learn something and every bit helps.
     
  13. fasteddy

    fasteddy I have C.L.A.P Global Moderator Generous Elf

    Joined:
    Apr 26, 2010
    Messages:
    6,497
    Likes Received:
    22
    Location:
    Albion Park NSW
    Find Me On:
    The forum and wiki have a wealth of info if you know where to find it. So here is the link to the spec sheets on various chips
    http://auschristmaslighting.com/wiki/Data_Sheets
     
  14. OP
    OP
    BundyRoy

    BundyRoy Dedicated Elf

    Joined:
    Apr 9, 2014
    Messages:
    1,026
    Likes Received:
    9
    Thanks Eddy. Just had a look at the specs for ws2811 and it lists one of the features as "Any two point the distance more than 10m transmission signal without any increase circuit". Does this mean that they think the 10m transmission of data signal is possible. I also guess that all specs that come out of china probably need to be taken with a grain of salt.
     
  15. kane

    kane Dedicated Elf

    Joined:
    Dec 23, 2010
    Messages:
    1,021
    Likes Received:
    0
    Location:
    Trigg (Northern suburbs of Perth)
    Find Me On:
    More like half a cup of salt. :)
     

Share This Page