Dmx power draw

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Snunicycler

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Beginner question that I'm sure has been addressed elsewhere but I haven't found it yet. I'm in the planning stages of a display for my 1st year. I bought a pb16 board that I'll be assembling. It all looks fairly straightforward but I want to incorporate the c9 LEDs (white, dumb) that I always put up. I plan to do some simple slow fades with them and my initial thought was to use the DMX screw terminals that are included on the board. Easy enough

Ok but then I finally started doing the math, the bulbs are .58w, and I have 200 of them on 12" spaced stringer (so about 200' plus the lead), so that's 116w. If I use a 12v power supply that's what, 9.6 Amps? Seems like a lot... Is this going to work?

They are currently all powered from one plug, but I can change that if I need to. Thanks!PXL_20201202_013121469~2.jpg

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Dumb white leds are powered by what? Usually 110v for dumb single color. You can't change how they are powered without significant changes to the strings.
 
To clarify, I'm planning on dimming them all together, not individually or anything. And yes, they typically are plugged in to the 110v from the house.

Now, maybe I'm biting off more than I can chew but my plan is based on those cheap 3 channel DMX controller things like David at Learn Christmas Lighting used in his article/video about controlling traditional lights. He had just 2 stands and uses a small 12v per supply like you would see on a small appliance or something, so right off the bat I'm scaling this thing up significantly. But it LOOKS ...possible... but you know it'd suck to burn the house down or something.

https://www.learnchristmaslighting....-controller-for-traditional-christmas-lights/

Thanks!

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He is driving the 3 mechanical relays with 12v but the relays themselves are switching standard 120 volt. You won't need much 12 volt power for that board. And it will switch 110v on and off with NO dimming. Those blue boxes are mechanical relays. There is spring inside that is pulled "on" by a magnet and springs back to off. The Songle relays are usually rated for about "100,000 operations. Min. (at rated coil voltage)" (that from a spec sheet for a particular version). That means if you switch them on every 5 seconds for 4 hours a night, you can expect failure at 35 days. And again, you would have no dimming.

For AC dimming, you want a triac or mosfet based dimmer. What we usually refer to as a solid state relay (SSR). And you want that relay to have the property "random". Random allows the relay to turn on when it is told otherwise the relays will wait until zero cross and that will cause no output with many controllers.

If you are looking for a product, check https://experiencelights.com/pixel2ac3-ready-to-run/ This would be something you might use and could be put in line with a pixel string (it uses ws2811 protocol for control to dim the AC line voltage). You would still have to check the amps but if your string is 116w at 120 that is 1 amp and this controller or similar could handle that or could use additional outputs to control string #2.
 
MikeKrebs said:
If you are looking for a product, check https://experiencelights.com/pixel2ac3-ready-to-run/ This would be something you might use and could be put in line with a pixel string (it uses ws2811 protocol for control to dim the AC line voltage). You would still have to check the amps but if your string is 116w at 120 that is 1 amp and this controller or similar could handle that or could use additional outputs to control string #2.
Click to expand...

After looking into the solutions you suggested, I think this Pixel 2 AC bridge is exactly what I need. I do have 2 wreaths I thought I'd have to get rid of so the 3 outputs on here are perfect and my conservative estimate of the total amperage should be about 2.25 amps total on the board - maybe even less, I'll know when I get them out of the attic later on.

Thanks again!

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