Help Troubleshooting

[oyarsa]

I have 4 arches with 50 pixels in each. These are connected to two sets of pathway lights from Wally's Lights, which are then connected to a Boscoyo Megastone.

I have the arches set to 60% brightness on my Falcon F16v4. The rest of the lights are 20%. There is about 25 feet from the controller to the arches. I have power injection after the arches using a non-pass through connection in case I decide to use 2 power supplies.

When I test the lights on white, the arches are fine, and the megastone is fine (which is after the pathway), but the pathway lights are red. If I turn off just the arches, the pathway lights turn to white. Adding an F-amp after the power injection makes the pathway lights show all three primary colors, but not really white. Again, turning off the arches fixes the problem.

Any thoughts?

[Srmorgan]

Sounds like you need more power inj. on the pathway lights.

[MikeKrebs]

Red is usually the least sensitive to voltage drop so the suggestion to add power seems to fit. .

Surprised the f-amp improved things.

I wonder if you just decrease the arches down to 20% temporarily if that helps.

Since you already have PI available, it makes sense to add power. But your comment about adding from a second power supply with a passthrough doesn't sound right. If it is a regular PI, then add from the same psu. If it is a PI tee with power pin disconnected???

[1pet2_9]

I've been messing with sharing 2 power supplies, to see what rules I can break. At 12v, it's clear: you just can't. Immediate results, and not good ones. You have to break the vdd line. But at 5v, if the injection points are 100 pixels apart, I don't see any problems. Which sure saves a lot of headache if I don't have to break it.

[algerdes]

Keep an eye on the power supplies where you don't have a split. The resistance between your connections may help, but to be honest - if the power supplies are not made to be put in parallel (with associated controls built in) then your two power supplies (or more) may be fighting each other. This has been known to shorten the life of the PS units, at least in our testing in prior years.

As always in this hobby, if you find a way to make them work, please let the rest of us know. Some of us have tried, but haven't had too good of results on the average.

[1pet2_9]

What I did was, I used 50-pixel strings. The shared PSU's are 100 pixels apart. When I probe voltage in the middle with all pixels off, the voltage is lower than either PSU. So there is no way my 5.2V PSU (for example) will drive reverse current into my 5.1V PSU. And it's just such a pain to break just one line there, when all I otherwise have to do is just connect the connectors. And of course I try to keep my PSU's more-or-less the same voltage, but I'm not perfectionist about it. So at least for now, if I am 5V and the PSU's are at least 100 pixels apart, I consider splitting the VDD line optional. But only then.