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Could someone tell me exactly what resistors/DC transformer/gauge copper wire I need? Maybe even provide some links? Answered

So I'm trying to make this:


and I bought 20 of these Blue 10mm superbright LEDs 1025LB7C

Could someone tell me exactly what resistors/DC transformer/gauge copper wire I need? Maybe even provide some links?

Maybe even provide some links?


get a power supply you'd want to use

use this link to find the setup of leds and resistors

the wizard also says how much current the entire setup takes. check that the power supply can give atleast this current

its unlikely that youll have currents where wire thickness is issue. acceptable load for wires is up to 10 A / mm2 (about 13 A if wires are free in the air)

I saw that site before, but I though I would need to choose the DC transformer so I could choose the voltage before any of that. I don't really get why I need one anyway. I would assume it would transform AC current into DC but isn't that what a AC transformer does? Could I just use batteries?

build what is going to work for you

if you have an existing power block - see its voltage and whether you can design for it

this can be powered from batteries too - but batteries have limited lifetime and pollute the earth at the end of it

leds can work on ac but they flicker. to have smooth light you should use dc. ac can be converted to dc of the same voltage and current with a rectifier bridge - 4 diodes and capacitor

So batteries are DC? As far as polution goes I have rechargeable batteries, but a plug in would be much more convenient. I have a 12 volt AC transformer. Does this transform AC to DC, I tried to check and it seems some do and some don't? I definately want DC. It has 2 red leds (as in the wires coming out; I believe that's how you spell it, but wouldn't this create some confusion with LEDs?) and a green led. I assume I need to use the two red but how could I find out which is positive and negative, because I know enough to know LEDs can only be placed a certain way.

batteries are dc

transformer is an internal component inside a power block. (sometimes the entire block is called transformer but its not correct)

transformer outputs ac

a power block may include rectifier bridge that turns ac into dc

to know whether your block outputs ac or dc see the output on its label.

if its ac youll see there ac or a sign of wave. there are no + - in ac

if its dc youll see there dc or a sign of = where one of the lines is dotted. you may also see + - signs. if no then usually red wire is + and blue or black is -

when connected to ac leds work in both directions but flicker

when connected to dc leds work smoothly but only in 1 direction

you can use a rectifier bridge (4 diodes and capacitor) to convert ac to dc

if you give dc into a rectifier bridge it outputs dc - it has no effect

no matters ac or dc - allways connect leds with appropriate resistor

Sorry I'm new to electronics and I'm reading a book about it, but so far I've learned more about measurements that circuits.