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By natural
#163336
Hello all,
Newbie here. Pretty new to electronics. I am working on a sculpture project, decided I would like portions of it to illuminate in a variety of colors.

After some brief research, I ended up purchasing some of these guys:
http://www.vozop.com/index.php/ws2801-d ... -leds.html
and one of these:
http://www.ebay.com/itm/SPI-RGB-LED-Con ... 25715d9503

My problem is, I can't get this setup to work. Generally what happens: plug in controller (led module already attached), module will illuminate a dim blue on all 6 led's, controller will flash through all IC's shown on the front (flashing red light behind the writing on control box), then usually all 6 led's will go full white for half a second, then completely off. Controller generally settles on one of the IC's listed (red light behind the writing on control box). Clicking through modes, IC's, speed on the controller changes nothing on the led module (still off).

Occasionally, after disconnecting and reconnecting power, I'll get the usual dim blue, followed by continuous full white until I change anything on controller, at which time led module turns off, and won't come back on again. ONCE, after disconnecting and reconnecting power, the module did it's normal dim blue, white flash, then started controlled fading through colors starting with red (I believe as it's supposed to). This only lasted for about 3 seconds, followed by turning off.

I've checked power output to the led module, 12.2v. Checking data/gnd & clock/gnd with the multimeter, I'm getting a low undulating voltage that changes depending on what mode I've clicked to on the controller (all while led module is off). If I check data/gnd upon connecting power, I get approx 5v for the duration of the dim blue, then it jumps to the low undulating voltage.

I'm at a loss. Any help you can give would be much appreciated! I will provide as much diagnostic info as I can.

Many thanks in advance!
By Tomdf
#163375
Hrmm, I can't find much documentation for either of those products so it's really difficult for me to say what's going haywire. Did the controller come with any kind of instructions?

It sounds like your connections are good since the LEDs are turning on and they are changing color. I'd put my money on the control signal being weird. Have you set the controller to use the ws2801 LED so that it is sending the right control signal? I'm only assuming that needs to be done because of the "Set-IC" printed on the outside of the controller.

Back to the instructions, do you know what the different modes should do, what patterns it should display? That would be very useful for figuring out if it is doing what it is suppose to or not.
By Mee_n_Mac
#163424
I might suggest only connecting the power and ground to the LED and powering it up. Observe if that's any different from having the controller truly attached. If not, then the controller isn't talking to the LED for some reason (wrong controller choice, bad wire, bad connection, ???). If it's really different then we might assume the controller is talking to the LED at some level. Perhaps there's line ringing or some other data loss. Hard to diagnose that or recommend a fix if true.

BTW your link specifies a single LED module (containing 6 RGB LEDs), not a string of such modules. Is my understanding correct ? If you really have a string then I strongly suspect that you are trying to power the whole string from the controller 12V output and it can't do it when all the LEDs are full on. Try using another 12V supply but keep a common ground btw all the components.
By natural
#163486
Thank you for your responses.

I've been in the same boat as far as documentation goes. Making guesses based off of the labels on the controllers and the descriptions from the sellers. I attempted to methodically press "Set IC" at different intervals to try and select the right controller, but it seems to have no affect. As far as I know, the modes are supposed to cycle through colors, but I have no firm description of how many modes there are or how they specifically cycle.

I have tried attaching both the controller and the LED modules to the power supply terminals instead of powering the modules from the controller. I also tried to run only one module instead of the string to see if it was a power draw issue. Mee_n_Mac, you are correct there are 6 LED's per module.

I had a suspicion that it might be a communication problem, so I acquired this controller to see if it was any different:
http://www.ebay.com/itm/160935851350?ss ... 1497.l2649
Alas, I get a little more activity, but not control. With this controller, one led module (attached directly to power supply), I get what is essentially full white, but it seems to pulse as if under control. In other words, at a glance it's full white, but upon close inspection, the individual colors appear to be changing output, but not enough to keep it from appearing full white. Changing modes alters the pulsing, but still not individual colors. With just power connected to the LED's (not connected to controller) I get full white.

I'm at a bit of a loss. My feeling is that it's a communication problem, but I'm not sure how to diagnose. Do you think it could be the LED modules themselves? Should I try to get another type of WS2801 RGB LED to test with these controllers? Have any of you guys used a similar setup I could check out?

I'll attempt to play with them some more. Supposedly the second controller comes with software to edit the programs, I'll see if I can't check out the "preloaded WS2801 effects" in the program to get any further info.

Thanks again for your help. I'm bummed I can't figure this out.
By n1ist
#163488
Try swapping data and clock. Wouldn't be the first time someone got those mislabelled...
/mike