SSC V2 has an output problem (prev - code has a bug)

[Steve Gase]

9.7v vs. 9.3v?
I'd start looking for bad solder joints or something going on in the RJ45 pigtail.
The 12v for the strings flows through the ssc, but it should not be reduced or limited by the ssc. Whatever you have at the input should be present on the output.

I'm guessing that the increased drive may increase the current draw a very small amount, but to get a 0.4v drop in output voltage just by swapping a v2 for a v1 ssc tells me there is another issue like a broken wire or you are running it on a 500 ft cable... Which would be a bit excessive.

RM

keith's confirmation seems to question a cabling or soldering problem.  also, I thought (but maybe assumed incorrectly) that MrC had multiple v2s which had the same issues.

[pk]

The more I read this, it sounds like a voltage distribution problem.  I measured a 0.25 volt drop from my SS Hub through a 6 foot CAT5 cable, to the output of a V2 SCC with 20 square nodes attached all on (white).

[tbone321]

Now this I can confirm. On ssc v1 white is brighter(like a warm white). On the ssc v2 it has a more blueish color(almost a cool white). But just reducing blue won't make it match the color of the ssc v1. You can't tell on just red, blue, or green. With yellow it is really close. With red and blue on their is a big difference. scc v1 is more of a fusia color. SSC v2 is more a light purple so their is more red on ssc v1. With blue and green on, ssc v2 is more a true baby blue and the ssc v1 has a little too much green in it. These are all ip68 pixel nodes Ray replaced in Jan for me. Bottom line there are color differences between v1 and v2 probably due to the increased level they are being driven at. I am not saying the colors are bad but you may want to not mix versions in your display.

I don't know what you mean by level.   What you need to check is the voltage output on the 12V side of the controller under load.  If one is putting out less voltage,than the other, I would look at the one putting out a lower volage for bad solder joints and make sure that there are no broken wires in the dongle that could be limiting current flow.  The controller has no control in the shading of the nodes other than sending the commands to the nodes an since both of them send out the exact same commands to the nodes, that can't be the issue.  The V2 sends out a signal that can sustain a much higher load than the V1 but that is not what sets the color.

If one difference between v1 and v2 is the resistors being used, wouldn't that translate into the intensity of the pixels at some point?

Nope.  Those resistors are in place to restrict the current being drawn from the outputs of the pic but that is the control signal.  Since the new design uses 3 or was it 4 pins from the pic, more current is available so the resister value was reduced.  The current here does not affect the color of the node, justhow much f a load they can put on the signal.

if the SSC is providing 256 levels for each channel and v1 provides 256 levels over the voltage 0v-9.7v and v2 provides its 256 levels over 0v-9.4v -- wouldn't it be reasonable to expect the strings using v1 to look "brighter" than v2 when everything else is the same?

Don't confuse smart and dumb nodes.  The smart string controller simply send a command to the nodes that tells it what level tp go to and with PixelNet, it's really 255 since 170 is a reserved command and is never sent as a level to the nodes.  Dumb string controllers are what sen actual levels of voltage to the device that they are controlling.  As for brightness, that is a relative term, especially wit LED's.  LED's have a very different dimming curve than Icans and in many cases wven withdiferent color LED's.  A slight voltage change could affect one color LED more than another which would change the color of the node.  If you are using only one color, then you might see a "brighness" change.

It was also my understanding that the voltage at the end of a string is lower than at the start -- because each pixel takes out its share of the current.  as a result, there is a subtle difference between the intensity at the start of the string, and the intensity at the end.

isn't the same thing at work here?

That is due to voltage drop in the 12V wires.  The same thing happens to landscape lights which have no control signal at all.

The V2 sends out a signal that can sustain a much higher load than the V1 but that is not what sets the color.

I thought red, green, and blue each have different color characteristics when you compare them to the other... they do not evenly lower as the levels are decreased.  so i'd expect voltage to again play a role with color.  if you step "purple" down from level 255 to level 0 by decreasing the red and blue at the same rate, I'd expect the color to SLIGHTLY shift towards blue at one point, and towards red at another point because they are different in how power translates to visible light.

maybe i'm way off on these suppositions.   my wife would tell you it wouldn't be the first time.

You are correct here bu the voltage is the 12V not the signal. 

[chrisatpsu]

in both situations (smart and dumb nodes), the leds are controlled by pulse width modulation, so there is no reduction in voltage. when it's on (even for a fraction of a second, it's full on, and when it's off, it's full off. The only thing that changes is the duration.

so, now that a lot of ideas have been thrown around, and lots of things have been tried....    does the first node still act up, or does that still happen now? (your original problem?)

[keitha43]

I am going out of town for a few days and will try another set of both versions and on different pixel sets to see if they act similarly Tuesday if nobody else tries this before then.

Sent from my Thunderbolt using Tapatalk 2.

[Steve Gase]

i appreciate the discussion, thanks guys.

[MrChristmas2000]

Just a quick note this morning before I do further diagnosis.

The color difference problem does occur over multiple SSCs.

The first pixel problem with the  hybrid programming seems to have stopped during my last test. Its one of those mysterous problems that couldn't quite be tied down to a source.

[chrisatpsu]

so.....

yay! first problem somehow is solved, and now you're dealing with color correction?

I'm assuming....

all your SSCv1's act the same with the leds...
all your SSCv2's act the same with the leds...
but...
your SSCv1's act differenly than your SSCv2's?

maybe RJ can chime in. does the SSCv2 produce a different voltage or amperage to the leds?

[RJ]

Nope,

 The 12 volts is passed throught the controller from the input to the output with nothing in between.

The output of data with increased current capacity does not change the data. the chips on the leds themself create the level of light output based on the value sent to them. It should not be possible for the change on the SSC v2 to change the output. It outputs ones and zeros which can only be in one of two states and this is controlled from your software. There must be some other variable being missed.

Different input voltage will vary the level because it is based on PWM by the pixels chips and that means it is 60% of something if set there. 60% of 11 volts is different than 60% of 11.5 volt as an example.

RJ

RJ

[dpitts]

I think they said the only 1 resistor value was changed. And resister was related to data line only. The other change of connecting four pins to data line was data only change also. So where is a change that would make colors different?

[dpitts]

Rj beat me. I hate typing on my phone.

[mykroft]

google voice to text is your friend on your android phone

[rm357]

With the LEDs off, you should have pretty close to 12 volts at the ssc. If not there is probably a wiring problem - the ssc by itself should not be drawing enough power to cause a significant power drop.

The cat 5 cables have some resistance - 25 ohms per 1000 feet for 24 gauge wire. Skipping all the math, with 3 wires for ground and 3 wires for hot on a 100ft Ethernet cable you would have about 1.6 ohms of resistance in the wires.

If you had a maximum length string all on, you could pull 4 amps, which would drop the voltage at the SSC to about 5.6 volts - which is still high enough to run things...

[keitha43]

All I know is I saw color differences. When I get back from my mini vacation Tuesday I will try different v1 & v2 ssc's along with 2 different sets of equal number nodes if nobody else has tested theirs by then. It wasn't noticible on single red, green or blue and I probably wouldn't have noticed the difference until Mr Christmas mentioned it. I tested with both last years and this years ssc's programmed to the same start channel so I could have both nodes on side by side at the same time and tested both in xlights and lsp. It was most noticable in white and red and blue on. Anybody got any old and new ssc's to test besides me?

Sent from my Thunderbolt using Tapatalk 2.

[tbone321]

Did you swap the string on the controllers and were both controllers set to the same addresses?