Bad dumb nodes

[devoidelk]

Wow. I was going to switch over to just dsc for next year since they have the same effect as the ssc except for the individual control but with this kinda failure rate old fashioned incans seem to be my best bet.

[jnealand]

I have not seen any failures on my dumb strings so far, but I do not have many in the display at this time.  I have tested more, but they are not in the display.

[kjam22]

Jnealand - are you powering them with a dsc or with some other device?  I have a 10 channel dmx rgb contoller from ray I might try to see if I have less failures.

[davron12]

Yes, are you using a dsc to control your dumb strings? I'm still waiting to hear from someone that is controlling dumb strings with a dsc that isn't having problems.

devoidelk - I wish I would have used all ssc's this year and just treated the pixel strings has a dumb string. Out of all the thousands of pixel nodes I have this year, I've only had problems with 2 nodes.

[JonB256]

Davron, I still haven't put a scope to it (I'm off on Friday), but reviewing your posts, I see that your 12vdc power supply is "adjustable" not an ATX computer power supply.

It is possible that there are voltage spikes from your power supply when it is switched on and off (even at the as yet undetermined  PWM switching rate).

Could you put a resistor (say 200 ohms or 330 ohms) across the power supply output? That would put a fixed, minimum load on the supply and reduce any wild swings. Not knowing the quality of the power supply's circuitry, it may be oscillating. A load resistor would stabilize it.

At 12vdc,
a 300ohm resistor would pull about 40 milliamps. That would be 1/2 watt.
a 1000ohm resistor would pull about 12 milliamps and just over 1/10 of a watt.

Watt do you have on hand?? 

[jnealand]

I am using a DSC to control my one string that is in actual use.  The others were to go with my big star on top of my mega tree, but I had to many things intefering with my getting everything done before I had to give up and put my old star back up or I wouldn't  even have a mega tree this year.  The DSC is just plugging into a passive hub and seems to be fine.  I have not noticed any bad nodes at all (something I cannot say about my smart strings).  Maybe I am lucky, I am using a PC power supply on the passive hub.

[davron12]

Davron, I still haven't put a scope to it (I'm off on Friday), but reviewing your posts, I see that your 12vdc power supply is "adjustable" not an ATX computer power supply.

It is possible that there are voltage spikes from your power supply when it is switched on and off (even at the as yet undetermined  PWM switching rate).
...

I'll see what I have available and try that.  The first 4 strings that I burned in were connected to an ATX power supply and ran into the same problem.  So I'm not sure that's the culprit.

I'm attaching the pics you requested here as I couldn't find a way to do it in the PM. The dsc's are wired the standard way as described in the wiki.

I am using a DSC to control my one string that is in actual use.  The others were to go with my big star on top of my mega tree, but I had to many things intefering with my getting everything done before I had to give up and put my old star back up or I wouldn't  even have a mega tree this year.  The DSC is just plugging into a passive hub and seems to be fine.  I have not noticed any bad nodes at all (something I cannot say about my smart strings).  Maybe I am lucky, I am using a PC power supply on the passive hub.

Are you using the DSC from this past group buy and when did you purchase your dumb string? I'm using DSC kits from this group buy You are not allowed to view links. Register or Login and purchased my dumb strings from Ray Wu 3 months ago.

kjam22 - when did you purchase your lights and controllers and as kits or pcbs?

[jnealand]

I have 4 controllers from the coop and 4 that I built by buying pcbs from the store and parts from Mouser.  My dumb strings are the ones in the wiki.  I went back to my order to check and the link is identical.  Just my gut, but I am suspicious of your power source.  You seem to be  the only one posting about node failures and if there were major issues with the nodes, I believe we would be seeing a slew of posts about bad nodes just like we saw with the original smart nodes.

[SteveMaris]

I have a few hundred dumb nodes controlled by MR 16's this year.
0 failures.

[mokeefe]

I bought 12 of the 100 pixel dumb strings from Ray.  I have about 4 to 5 failures on every string.  It is always either the red or blue (or both) LED that is out, never the green. I am using DSC's with ATX computer power supply to control them.  The strings are spread over 3 different hubs/power supplies. Due to time constraints I didn't do much testing of the strings prior to setting them up outside so I can't say if this if these failures were there initially or have occurred since running them.  I don't think I'm seeing increasing failures since my show has been running, but I haven't done specific counts.  My sense is they are just bad or marginal nodes -- perhaps a bad run from Ray.  I'll be contacting Ray to get replacements nodes and will have a do a bunch of splicing at the end of the season.

-Mike

[JonB256]

I have a few hundred dumb nodes controlled by MR 16's this year.
0 failures.

Davron, when I get your DSC hooked up, I'll compare the output to an MR16. They use the same MOSFET output.

Mokeefe, my dumb pixels are like Ray's but not from Ray. I have a few pixels that want to flicker at full power but seem fine at lower power. No complete failures, though. They are on an MR16.

[davron12]

I have 4 controllers from the coop and 4 that I built by buying pcbs from the store and parts from Mouser.  My dumb strings are the ones in the wiki.  I went back to my order to check and the link is identical.  Just my gut, but I am suspicious of your power source.  You seem to be  the only one posting about node failures and if there were major issues with the nodes, I believe we would be seeing a slew of posts about bad nodes just like we saw with the original smart nodes.

It could be power supply related, but I've have the same problem with two different types of power supplies - 12vdc led 400 watt power supplies, and an ATX power supply. I'm not the only one posting about failures, read the thread from the beginning. I think I'm just the one with the biggest mouth. Sorry.

So far, you're the only one using a DSC with a dumb string that has reported success, at least on this thread. Everyone else is using DSCs with other lights or using MR16s to power their dumb strings. I guess the one thing that's different about your situation is that you're powering just one string, so that is a lot less of a current being switched on and off.

I have a few hundred dumb nodes controlled by MR 16's this year.
0 failures.

Definitely seems to be DSC & dumb string related. Not either one alone. Seems very odd that everyone using MR16 hasn't had a bad node, but myself, mokeefe, kjam22, mitch09, and frankr are reporting between 5-10% failure rates.

I bought 12 of the 100 pixel dumb strings from Ray.  I have about 4 to 5 failures on every string.  It is always either the red or blue (or both) LED that is out, never the green. I am using DSC's with ATX computer power supply to control them.  The strings are spread over 3 different hubs/power supplies. Due to time constraints I didn't do much testing of the strings prior to setting them up outside so I can't say if this if these failures were there initially or have occurred since running them.  I don't think I'm seeing increasing failures since my show has been running, but I haven't done specific counts.  My sense is they are just bad or marginal nodes -- perhaps a bad run from Ray.  I'll be contacting Ray to get replacements nodes and will have a do a bunch of splicing at the end of the season.

Mike, you may want to hold off splicing. kjam22 and myself had fixed some of our strings, just to have them burn out again.

[chrisatpsu]

is it always the red?

[mokeefe]

is it always the red?

In my case the nodes lose the red, blue, or both channels.  I don't have any that are missing green.

-Mike

[davron12]

Red seems to be the first to go within minutes of being on, leaving a blue-ish looking node, and this is by far the most common problem. After being on for hours, some of the blues will also burn out, leaving green or yellow nodes. I haven't had any greens burn out either. The bad nodes are concentrated near the beginning on the strings, but can occur anywhere.