15 meters of RGB

[SpacePumpkin]

Not really sure where to post this, off-topic seemed the best place but correct me if I'm wrong.

 

Last year at my student accommodation, I decked my room out with 15 meters of LEDs following the edge of my room, I loved it, controlled by an arduino and my own android app, I could set custom patterns, make it respond to music but most importantly, mimic the sunset so to not upset my circadian rhythm.

 

This was all powered by two separate power supplies at opposite sides of the room and the voltage drop was barely noticeable (when setting to full white bright the ends of the strips would be a mottled pink/yellow colour - I even set my own "full bright" at about 80% power with a bluey tinge just so it was uniform).

 

I want to repeat it this year, with brand new strips (the old ones didn't make it through transit to the new place), however, my room is pretty much a converted bathroom with a tacked on extension and there are only 2 twin socket outlets on the SAME side of the room. I know very little when it comes to electricity but I do know that each socket is rated at a 13A max and I need at most 27A for 450 LEDs at full bright (I've made my peace with not being able to attain this, but its useful for calculations at least). What I don't know though (and the internet can't seem to agree on an answer) is if my 2 physical outlets will both give 13A or if ALL sockets in my room can only give a max of 13A. As well as this, how far away from the outlet can I provide power (through means of extension leads) without losing too much of these 13A?

 

tl;dr Does a room of outlets only give a max of 13A or is this per socket? (where having two physical sockets would provide 26A). And How much of this power would be lost by trailing extension leads to the other side of the room (about 5 meters)?

 

Thanks!

[klh2000]

So assuming that the 27 amps is at 12 v for the led strips, that's 324 watts. At 240v (from the wall socket) you would only be pulling about 1.4 amps from the wall socket. You could run an extension lead no problem. The voltage drop would be negligible.

[SpacePumpkin]

So 27A flowing through the strips is different to the amps actually pulled from the wall? I also forgot to mention that I'm in the UK, the strips are at 5v 

[klh2000]

4 hours ago, SpacePumpkin said:

So 27A flowing through the strips is different to the amps actually pulled from the wall? I also forgot to mention that I'm in the UK, the strips are at 5v 

Yes, the amps will be different when changing voltage. So if your at 5 v and 27 amps that is 135w because p=IV. So if you want to find the draw from the plug socket, it would be I=P/V. So at 240 v it would be 1.8 amps.

[SpacePumpkin]

Awesome thanks, next question. One of the three strips has the option of being powered at both ends, how could I do this safely? Would it be as easy as connecting the 2nd power supply +/- to the end of the strip (with it being powered by the 1st supply at the start of the strip)? Or do I have to cut the cable somewhere in the middle to prevent the + power from both supplies touching?

[klh2000]

5 minutes ago, SpacePumpkin said:

Awesome thanks, next question. One of the three strips has the option of being powered at both ends, how could I do this safely? Would it be as easy as connecting the 2nd power supply +/- to the end of the strip (with it being powered by the 1st supply at the start of the strip)? Or do I have to cut the cable somewhere in the middle to prevent the + power from both supplies touching?

Well, it depends. If you are running a single color led strip, then you can connect a power supply at each end, if the supplies are identical. I'm not sure how RGB strips work as far as using multiple supplies, but the same principal would probably apply.

[SpacePumpkin]

10 minutes ago, klh2000 said:

Well, it depends. If you are running a single color led strip, then you can connect a power supply at each end, if the supplies are identical. I'm not sure how RGB strips work as far as using multiple supplies, but the same principal would probably apply.

Thanks, I might just not  most places I've found on the internet only talk about hooking the same unit up several times, but thats impossible with my planned setup. Safety is more important than getting above 80% brightness   (my WS2812B strips are full RGB with a +5v, gnd and data wires)