WS2801 Pixels

C

chilloutdocdoc

Full time elf
Joined
Jun 5, 2010
Messages
114
Location
Central Florida
 
I would never trust any IP ratings. For that matter, one time you might get a great batch and the next batch is junk. Oh the excitement!
 
chilloutdocdoc said:
So, I'm looking to make a purchase from Ray to start testing some lights and configurations.

Does anybody know if there's a difference between these other than the apparant IP67 or IP68. (Do I really trust them anyway?)

Which one would you recommend:

http://www.aliexpress.com/fm-store/701799/209889132-404056686/12mm-WS2801-pixel-module-IP68-DC5V-input-full-color.html
Click to expand...
These are the ones im looking at getting, they seem to have the added weatherproofing protection on the moulding. I dont know if the cable is UV protected though.
Has anyone else ordered these ones who are able to report on how good the cable entry moulding is.


chilloutdocdoc said:
http://www.aliexpress.com/fm-store/701799/209889132-449802558/12mm-WS2801-pixel-module-IP67-DC5V-input-full-color.html?tracelog=back_to_detail_a
Click to expand...
I have no idea on these ones but they are the cheapest of the bunch


chilloutdocdoc said:
http://www.aliexpress.com/fm-store/701799/209889132-320389559/12mm-8mm-led-pixel-RGB-led-channel-lettet-waterproof-WS2801IC-256-level-gray-scale-DC5V-input.html
Click to expand...
These ones are similar to what I used last year and I had no issue with them at all even with rain. But these ones dont have UV protected cable.

The ones i used last year were http://www.aliexpress.com/fm-store/701799/209889132-320677241/12mm-8mm-led-pixel-RGB-led-channel-lettet-waterproof-UV-cable-WS2801IC-256-level-gray-scale.html

They are a bit more expensive than some of the others but i was very happy with them. But as i said above the first ones you linked to look very interesting as they show that they have added weather protection on the cable entry.
 
Check out This thread.

Whilst the 'improved sealing may seal the wires better there are a couple of issues to consider/specify

1) Distance between pixel centers - the new sealing is longer... so the distance between pixels is effectively shorter.

2) The new sealing method pixels may use higher gauge wire (with higher voltage loss) 22 vs 20 in the sets I got.

3) There are 2 types of plastic/resin used in the new seal. A harder plastic shell and more flexible stuff in the middle. The 200 'new seal' pixels I received from Ray in Jan hadn't cured proprerly.. so the internal material had gaps between the inbound and outbound wires that should probably be resealed. If I was worried about it I would have specified that they need to be cleanly sealed at the back.

As to the UV protection... having used 'unprotected' cable for a season in Aus, my opinion is that its always been a bit of a beat up compared to the magnitude of the actual problem. There may be some discoloration of the cable (and the pixel case). But I don't have my pixels out all year round.. and given the rate things are moving I'm not sure how many years before they are obsolete anyway....

My advice is to be clear with Ray on what you need and what is important for your setup. Sometimes these things matter and sometimes they don't....
 
To quote ray
"sorry, it is not UV cable
but the spacing between node is about 10cm
actully, we can make any spacing for you
we use 22AMG cable"

So it looks like he can make any spacing, not sure what the cost would be. I'd be interested to see what a 30CM spacing would cost.

-2 for the UV
 
Had a few problems with the `blob on board` type pixels.

Seems to be related to mechanical fragilty, think stress on the cabling can be enough to fracture PCB traces and possibly the mounting of the chip on the PCB.

Not assaulting the strings , just a pull or a twist at the wrong angle seems to have been enough.

Personally looking for a similar pixel that uses an SMD or DIL version chip just for perceived mehanical strength.

Moving wire gauge up would help with having to run extra ground and power rail along arrays, the droop from yellow to orange looks well obvious ;-)

Any suggestions?

Cheers
Adam
 
You may want to try attaching the pixels strings to Polypropylene Strapping like this http://www.gordon.org.au/packaging/page_products_poly__pet_strapping.html

By using zip ties at the back of each pixel it will possibly remove the likelihood of the damage and them attaching them to the strapping it will both remove any stress off the joints and will also make them sit in a uniform position
 
That's a very interesting idea! I had been looking for something fairly light that could take the strain off the pixel wiring and yet provide a way to orient the pixels in the desired direction.

I'll have to do some testing!
 
For my Matrix frames I used 36" cable ties which worked very well. I used 4" cable ties to secure them and did not appear to have had problems with water ingress on the pixels.
 
I have ordered 2801s 3 times from Ray and each time I got slightly different pixels. The most irritating issue was that the distance between pixels varied from batch to batch. These things are typically used to stick into a matrix of holes in a sign, and in that application the length of wire between pixels isn't important.

If you're going to be hanging them, I suggest that you stress to Ray that distance between pixels is important to you. Connecting to a backing strap of some sort seems like a good idea, that way you could design around the minimum pixel spacing, and just have a bit of extra wire for the farther-spaced pixels.

The good news is the price has dropped about $0.10 USD per pixel from last year.

If doing the backing strap method, I would suggest attaching each pixel to the strap with a bit of hot melt glue. That should deal with any waterproofing issues as well.
 
In previous years I have used 5mm poly rope to take the strain off the incandescents, and this year I plan on using the same methord to hold the pixels and RGB LED's as well. Black rope, not seen at night, and less than the width of the wires, can then be stretched pretty tight to minimise any flutter or sagging of the lights.

Add some elastic at the base attaching to the ground and the lights then get held in place but wont be overly strained when hit by gusts of wind, a wild football, or the neighbours cat when punted like a football :D

I dont trust the IP rating of the Aliexpress pixels, but think the IP68 have to be better than the IP67, but I'd be adding additional sealing to them both anyway
 
You must log in or register to reply here.
Back
Top