Power Supplies
Intro
When your working with pixels or any type of led, they will be ran on DC voltage. To do that you will need to run some sort of power supply. There are many types you can use.
Waterproof Power Supplies
Waterproof power supplies are really nice in the sense that you do not have to really worry about moisture as much as a non waterproofed power supply. Now just because it says waterproof doesn't mean i would let it sit in the open. You should still put it in some sort of shelter just to be safe. These are a little more pricey than a standard switch mode power supply but alot less headache. They come in a variety of sizes so you will have to choose what will work best for you.
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With 5v the voltage drop will be noticeable if your trying to push the voltage for a long run. Most likely you will need to inject the power again or feed from the center of the pixel string. For every 50 pixels, you should re-inject the power. So a good example, if you have a 100ct pixels string you can connect the signal wires end to end, but you will either have to put the power at the center of the string to feed each side. Or you will have to put a power source on either end. A 50ct pixel string will pull around 3amp (50x.06=3amp). So really finding smaller power supplies is a good thing to have if you have your pixels spread around the yard. If you have like a pixel megatree then you can do a large power supply to feed the whole tree. So bigger is not always better esp if your not power alot of pixels close by.
12 volt is a bit different. You can push 12v further than 5v. So that does have its advantages and disadvantages. Most pixels strings are only 5v. There are some that are starting to 12v but it may be a bit before more start to come out. So 12v is alot nicer but not as many options.
Also with some of the waterproof power supplies they use waterproof connections. Those can be purchased from china. They are similar to what are used on rope lights. 'Add Picture'