WS2811 Technicolor Strings Have High Failure Rate

[spudman78]

 One strange thing is that some of the nodes after the failing nodes seem to be properly reacting to the data being sent to them.

[Steve Gase]

One strange thing is that some of the nodes after the failing nodes seem to be properly reacting to the data being sent to them.

could data in and out be bridged on the bad node?

[spudman78]

Maybe the part of the chip that repeats the data is still working but the part that powers the led is not?

[tbone321]

If it is the regulator that is failing, how are the rest of the nodes behind the failed node working at all?

The 12 volt line is jumper by a trace right across the board and it is the input to the 78l05. It is the output from the 78l05 that drives the node.

So as long as the circuit board itself is there you'll have the connection for the +12v and the ground side. It is the Data in line that gets passed into the chip and the chip produces the data out and that is what gets passed onto the next node.

Joe

I understand that BUT the data does NOT work that way. If a node is dead, the signal is not regenerated to the following nodes so even though they may be getting power, they should not be gettng any data and at best, they should either all be out or just random flahes.

[tbone321]

One strange thing is that some of the nodes after the failing nodes seem to be properly reacting to the data being sent to them.

This is my point.  If nodes past the failure are still operating, it appears tha the chip is still getting power and still processing data. 

[tbone321]

Maybe the part of the chip that repeats the data is still working but the part that powers the led is not?

If that is the case, then it can't be the regulator since the regulator powers both the chip and the LED. 

[spudman78]

One strange thing is that some of the nodes after the failing nodes seem to be properly reacting to the data being sent to them.

I will reconfirm this when I get home by doing some color washs, then I will yank them down and try them in the house after they warm up.

[spudman78]

Sorry for the misinformation, but when I tested the Technicolor nodes this evening, the nodes after the first node showing issues were NOT responding to the sequence I was running. some were lighting up white and some were other colors.

[dduck]

Sorry for the misinformation, but when I tested the Technicolor nodes this evening, the nodes after the first node showing issues were NOT responding to the sequence I was running. some were lighting up white and some were other colors.

This is what happened to me.   For me the bad node actually was working and responding to the sequence but it was
passing bad or no data to the following nodes.    If I put in a bridge on the data around the bad node the nodes after it lit up normally.

[dduck]

In case anyone is interested.   I tried to lower the voltage on my 2811 100-count TC along with different
intensity.   My power supply only goes down to 10.11 volt.     Connection was pixelnet USB to 4-port
passive hub to moded SSC2.  I used the test RGB background mode in xlights.

Lead length is 6' and spacing between nodes from pixel bulb center to center is about 2.6".
No other injection is performed on the string.

In all of the tests the dimming was not very apparent for 1 and 2 color tests.
I did not perform enough tests at white due to concerns for my string.

The following are the voltage reduction measured at the end of the string:

1 color 50% intensity tests:

PS voltage    reduction(%)
12.1v           15.0
11.01v         16.6
10.11v         18.1

2 color 50% intensity tests:
12.1v            25.4
11.01v          28.2
10.11v          30.5

3 color 50% intensity tests:
12.1v             did not test
11.01v           37.8
10.11v           not sure.   lights were blinking

3 color 25% intensity tests:
12.1               not tested
11.01v            20.5
10.11v            22.4


Bill

[Steve Gase]

Very interesting... thanks for sharing the info.


The blinking on 3-color 50%...  I assume that this "error condition" was caused by the lower voltage.


This makes me think that 8v would have even more problems under the combined stress of more colors and lower voltage...  would you agree?

[dduck]

Very interesting... thanks for sharing the info.


The blinking on 3-color 50%...  I assume that this "error condition" was caused by the lower voltage.


This makes me think that 8v would have even more problems under the combined stress of more colors and lower voltage...  would you agree?

Yes I think the blinking at the end of the string was because it was getting too low of a voltage.   I quickly
changed the intensity to a lower value

As for 8v, yes I would think you would have more problems at the end of your string mainly due not enough voltage available.
If you do not want to reduce intensity or colors then injection may be the answer.

 

[Made2Rock]

Thanks dduck, I played with adding a few diodes on the 12v line of my power supply last night to reduce the voltage. It work but I was having trouble with the lights. In my case I was using a zeus and this zeus has been trouble from the beginning so I am out of spare equipment so I'll need to pull some of the boxes back in and use them.

I've attached pictures of the Megatree to show more of what the problem is. To answer the questions ahead of time Yes the tree should be a solid color and yes the equipment driving it is all turned on. This is the best this can be

Joe

[tbone321]

This really makes me worried when I decide to further expand my nodes.  These things really seem to be a disaster and from what I'm reading, what you order is not necessarily what you are going to get. 

[Made2Rock]

I have a little test setup that I'll put to work this weekend. It is a Pixelnet dongle and a 4 port passive hub which I will power by a power supply that I can now get down to around 9 volts. I only have one test string but I'll pass on what I come up with.