Help with first time display...

[bandyman]

Hey guys and hello from the states. I'm finally going to bite the bullet and throw up some rgbs this year and really need some help. I've read the 101 guide but I'm still a little lost. I'm starting small and I'm only doing the front eves of my house which measures 60 feet. I going to use the ribbons http://www.holidaycoro.com/product-p/700-white-wp.htm lights
and this controller/power supply. www.holidaycoro.com/product-p/831.htm I will prob buy 5 strips and use vixon to program them. My main questions are what else do I need and how do I inject power (i see that term used but have no idea how to do it). Do i need additional cables to do that? Any help would be appreciated and I will answer any questions you have to help you help me...lol Thanks guys!!

 

[i13]

If you're starting this late then be prepared to accept that you might not get it working this year. The displays are year-round projects. Starting small is a good idea but you're really pushing the boundaries of what can be done let alone without the background knowledge.

Injecting power is quite simple but if you limit yourself to one strip per controller output then you won't need to do it. If you use two per output then it's worth a try without power injection because the website says the controller can handle it. This means the worst thing that can happen is your lights are underpowered and shine pink when they should be white. If this happens then you need to thicken, shorten or double up the power cables between the power supply and lights and try again. Fortunately you've chosen pretty much the most forgiving type of strip when it comes to lack of power injection.

If you still can't get them to shine white or if you want more than two strips per output then you will need to inject power. With those strips you'd have more than enough voltage if you inject power between every second strip. The data line is just connected from strip to strip as normal and so is the negative. You need to connect the positive and negative from a power supply to the points between every second strip. You'd be connecting the power supply at the 'wrong' end for every second strip but that's ok. Disconnect the positive line in the joins between the strips where there's no power injection. You should never leave the positive connected from one power supply to the next and that includes the controller.

I'm assuming you're using multiple power supplies as this setup will still work if there's only one supply. You don't need to disconnect the positive between injection points if you're using the same power supply but I still recommend disconnecting between the controller and first injection point to avoid having too much current flowing through the controller.

You might not be able to get much help with that controller. I have never dealt with HolidayCoro and nor have I seen that particular controller in person so I'm not going to comment myself. Just letting you know that this issue is there in the background. See reply 22 in this thread
http://auschristmaslighting.com/forums/index.php/topic,7180.0.html

It's very possible that you might be able to get away with less power injection.

 

[bandyman]

Thanks i13, I'm just gonna shoot for this year and if it doesn't go off then I'll just be ready for next year. I'm starting small just to get my feet wet anyway. So I was hoping with this few strips to just use one 350 power supply. As far as the power goes, so I understand what your saying... If I use a pixlite 16 (thanks for the heads up) it has 8 outputs per side so if I connect one strip to each output it would be fine? My next question would then be since I'm outlining my eves wouldnt they just all be connected in a single line? Also, you mentioned the data strip... is that what carries power and I would just need to connect every 2nd strip to inject power? Sorry for the noob questions but I'm still trying to understand if and exactly how to get additional power if needed. Thanks again.

 

[i13]

If you used a controller with more outputs then you shouldn't need to worry about power injection if you're only using 5 metres of strip per output and maybe up to 10. You can cut and join the strips to make them different lengths if you want to.

The main thing to watch out for with both the PixLite 16 and the AlphaPix 16 is that they only support 340 pixels per output. The PixLite 4 and AlphaPix 4 support 680 per output. Those strips only have 10 pixels per metre even though they have 30 LEDs per metre. The decision of which controller to get is up to you and I believe they'd all work for your purposes. If you're happy to inject power then the only disadvantage of having more pixels per output is that if one pixel dies close to the controller, all of the ones after it won't work until you replace the dud one.
The reason I mention the AlphaPix as a potential problem is that none of the experienced long-term forum members here use it and I don't think they will. That said, I don't have any PixLites or AlphaPix just because I already have enough other controllers. The biggest disadvantage that both the PixLite and AlphaPix have is they can only have one pixel type per controller at any time. You can still have pixel strings and strips together but they need to have similar chip types. Think of it as your pixels all need to speak the same language. J1sys controllers are more configurable but also more expensive. The F16v2 also allows multiple pixel types and it is exceptionally good value for money but it is only occasionally available as a group buy.

I mentioned the data line in the strips, not a data strip. The strips have three wires at each end, positive and negative power plus the data to turn them on.

Power injection is done due to voltage drop. The problem with only having one power supply is that voltage drop can occur in the long wires between the power supply and the lights. You can overcome this with DC-DC converters and a slightly higher voltage supply, you can add more power supplies or you can use much thicker cable. Although it doesn't damage anything, I have never taken chances with voltage drop so I don't know exactly where the limits are.

You're almost right with injecting power. Connecting the power supply between every 2nd strip would be more than enough power injection and this leaves more room for voltage drop to occur between the power supply and lights without causing problems. You connect the negative and data line from strip to strip as you'd expect. This is how you should wire them if you want to inject power between every second strip:

1. First strip - connect all three wires at the start to the controller.
2. Second strip - connect the negative and data wires at the start of this strip to the ones at the end of the first strip. Leave the positive wire at the start of the second strip disconnected. Connect power to the positive and negative wires at the far end of the second strip.
3. Third strip - connect all three wires to the end of the second strip where the power is.
4. Fourth strip - same as second strip
5. Fifth strip - same as third strip

You can (but don't need to) connect the positive between the first and second strips if you're only using one power supply AND you're not using fuses.

 

[bandyman]

Thanks... thats great info. So when you say connect power from the power supply to every 2nd strip is that another cable that I run from the power supply out to the strips?

 

[i13]

Yes it is. It is actually two cables; one for the positive and one for the negative. As I was saying the longer and thinner these cables are, the more voltage drop that will occur within them and that'll reduce the effectiveness of the power injection.

 

[bandyman]

Cool... So is there a cable you could recommend? Also, thanks so much for all the help... very grateful!

 

[i13]

I'm Australian so I don't know about which suppliers would be the best for you to try; there are American ACL members who should know. I use 24/020 cable which is roughly 18 AWG largely because I can get it cheaply. It never hurts to get something thicker for the power which is why I always double it to prevent having to worry about voltage drop. 24/020 cable is not all that thick and I haven't tried longer than few metres between the power supply and strips. Don't double the data wire; it doesn't need to be extra thick and the signal is likely to go corrupt if you double it.
The cable between the power supply and the controller might need to be very thick depending on how many strips you power through the controller.

It's probably worth getting a little bit more strip than you need in case you accidentally damage a section, if a pixel just dies or if you need null pixels. Null pixels are used when you want long distances of data (not power) cable between strips or between the controller and first strip. Coaxial cable might work instead between the controller and first strip but it depends on the controller type and no-one's tried it with either the PixLites or the AlphaPix. Coaxial cable works with the F16v2 but not with J1sys controllers.

No problem helping either; you need to learn somehow and you're doing something that I (of course) think is a great idea . Have a visit to the chat room too. You'll learn more there in a few hours than you would by searching the internet for days plus you'll get to meet the members of this community who have their own displays too. Keep asking questions you'll get those lights blinking for next year at the latest.