Hi from Hornsby, NSW

MrX

New elf
Joined
Sep 1, 2018
Messages
41
Howdy,

Last year we moved into a house with a nice street frontage and thought I would get into the Christmas lights thing. Being green at it I just bought a mish mash of lights and hung them up and all was good, until I discovered 8211's existed, as such what I did last year just won't do anymore.

I have a technical background, I play with APIs, IoT devices etc, so electrical things, programming, etc are not scary, just new elements to learn. Earlier in the year I purchased some bits to play with to get used to the tech before I took the plunge. Right now I have an E682 controller board, which is cool but I am eyeing off the Falcon. I have my test string of 100 x12mm pixels in a matrix on a bit of cardboard at the moment and am having fun with XLights. I also have a an AllPixel USB board and playing making some hand crafted animations with the Python libraries but cannot seem to get it working with XLights. Those boards may be a bust if I cannot them to integrate into the main system.

It seems I have my head partially around the tech now so I have ordered a bunch of stuff from Ray Wu. I still need to work out what I will use as a computer controller, I have a bunch of computing choices so that is no big deal. The main thing that I am still not decided on is power. I wouldn't mind making the light show a feature of the house and making parts of it permanent so to avoid extension cords all over the place I am considering permanent. It seems I can do it myself it is low voltage DC so am tossing up a centralised 48 volt system to help with voltage drop with outlets with back converters at strategic places to go down to 12. It also means that data wires can share the same conduits. Curious to know if this is the done thing or if I am missing something which means this is crazy.

I guess there are also some bits and pieces like cable management, enclosures and FM transmitter to consider. All in good time I guess.

That's about it from me, this looks to be a fun thing to do. Cheers.
 

keithsw1111

Senior elf
Joined
Oct 11, 2012
Messages
936
Location
Kellyville, NSW
Welcome ... from just over the Gorge in Kellyville.

While you can do the buck converter approach you need to be really wary of current draw as buck converters have limited ratings ... you also need to consider how the buck converter fails ... because they do ... if it suddenly passes through 48v your pixels are toast.
 

MrX

New elf
Joined
Sep 1, 2018
Messages
41
Hi, thanks for the welcome. Yup, just the other side of the gorge, here I wa thinking that glow on the horizon was sunset not your light show :). I was wondering about the loss and limitations of the converters and did not consider the failure mode. Are there step down transformers that go to 48V AC then a PSU to do 12V? May have to bite the bullet and get a sparky to help.
 

scamper

Dedicated elf
Joined
Jan 5, 2014
Messages
1,225
Location
collie
Hi and welcome to ACL
I second the buck converter limitation. I tried this with 12v supplies and 5v converters, but ended up canning the idea. The limitations mean I can buy more power in power supplies than buck converters for the same money. And I have overloaded buck converters in the past causing failure (and almost a fire)
To start with you can use any old computer, but as you grow the show and number of channels you will find it will start to slow down, first place you notice it is the rendering time while sequencing, then if you get past all that, you may start to see a bit of lag in your show. My suggestion for what it is worth is get a raspberry Pi and load FPP on it. You can set up your own network to keep if off your home network but still access it via wifi to upload sequences, change settings etc. and they are cheap :D
any time you are looking at buying stuff but are not sure, you can pop your wish list up here and there will always be someone to give their advice. Then it is up to you if you want to listen :confused:
If you haven't already, download the acl 101 manual and have a read, it is very helpful and has a huge amount if info in it.
 

MrX

New elf
Joined
Sep 1, 2018
Messages
41
Thanks... the more I look into it the more I think it is not the way to go. I certainly don't want to start any fires, given we are in a bush area and all. Now that would annoy the neighbours. I am curious why a Pi out performs a PC given they are not really all that grunty. Spare PC power is not an issue with me, I have 2 i7s running not doing much, a NAS and a bunch of old servers that were pulled from a datacenter years ago I cannot bring myself to toss out. I also have a spare Pi 3 which is what I will probably end up using for this once I get the architecture right.

I am a IT security engineer by trade, hence the hoarding of junk. I will certainly be segmenting my network for this, especially considering there will likely be some LAN cable outside. Tell me people don't just poke their LAN cables outside without proper segmenting? I have a bunch of firewalls I can use for this to lock that down. I do wonder how many people do this backwards and think they are getting security but in reality are not? I have not looked deeply into the docs here but is there a wiki entry on security? Could be something I can contribute if not.

Come on.. reading manuals and asking for advice? where is the fun in that? I don't want to waste all that money I have spent on fire extinguishers. :)
 

djgra79

My name is Graham & I love flashing lights!
Global moderator
Generous elf
Joined
Dec 27, 2011
Messages
2,163
Location
Cranbourne West
Welcome to ACL MrX!
Many people seem to be able to get away with 12v & 5v centrally or located near the props. So if you can avoid buck converters for these types of loads it may be for the better.
Looking forward to seeing your display progress.
 

videoman3857

Full time elf
Joined
Apr 21, 2016
Messages
445
Location
Glass House Mountains
Hi and Welcome !
To answer your Question - You're crazy ! :DxDO_O;)
While understanding your reasoning for 48V dc. I wouldn't go there.
With a bit of math, working out your power demand and voltage drop and strategically placing the correct voltage PSU for your lights is going to be way cheaper and easier than if your buck converters fail.
Jump in on chat and ask away, or post up anything in the forums
 

MrX

New elf
Joined
Sep 1, 2018
Messages
41
Well I think the crazy bit is official now :)... pretty sure I have been talked out of zany power solutions so will be looking at running standard 12 and 5 close to where I need it. Still working on some ideas regarding leaving some lights in situ permanently as a cool fixture but that might be a question for next year when I start to pull things down. I will certainly pop into the chat and post updates as things take shape. Right now I am just playing with trinkets as they start arriving. It really is dangerous how eBay keeps your credit card saved. Dining table now looks like a science lab with wires, breadboard and dismantled lights everywhere.
 
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