Adjust RGB with sliders for RGB Led Strips

[TheNuzziNuzz]

I wan't to use faders (Sliders) to control the amount of RGB.

 

Basically, my LED strips have 4 wires:

+12v

R

G

B

 

In that order

 

I want to use 3 sliders to each change the RGB. I don't know if they need to change the Voltage or Amperage. I also don't know what specs they need to be so they will be powerful enough.

 

So, I need some explanation to patch the holes in my electricity knowledge, Ideas on how I should do this, and parts recommendations?

[Hackentosher]

Are you dealing with addressable leds or the ones with individual wires for r, giving, and b? You could probably setup an if else statement with the sliders and each pin on the strips. 

[hambobolubia]

what do you plan on using for a powersupply? also do you know what the current draw of the leds would be?

 

[straight_stewie]

I'm pretty sure your LEDS aren't amperage controlled. Almost nothing is amperage controlled.

If your LED strip is just a voltage controlled strip, it's super easy: Hook them up at the end of your slider switch (assuming that your slider switch outputs within the strips requirements). If your LED strip is addressable, however, that's a different story.

[TheNuzziNuzz]

25 minutes ago, Hackentosher said:

Are you dealing with addressable leds or the ones with individual wires for r, giving, and b? You could probably setup an if else statement with the sliders and each pin on the strips. 

 

The leds are all in  parallel, so there are 4 wires that go through the start and end of the strip.

15 minutes ago, hambobolubia said:

what do you plan on using for a powersupply? also do you know what the current draw of the leds would be?

 

 

I will buy a 120 watt from Hitlights. They draw 12 Volts, 7.5 Amps total.

[manikyath]

the issue here is most LED strips are best controlled by PWM rather than actually "analog" control.

 

the easiest way (and one that i'm considering as well) is buying those LED blinky solder kits and making those do the magic:

 

those kits are SUPER common, and they basicly have the two pots that control the time each of the leds is on for.

 

so, easy adaptation: smaller caps = shorter blink time, small enough caps = PWM signal

 

at that point you just replace one of the pots with a slide pot, and keep the other one as a trimmer, then multiply by 3 and bodge into your LED strip and BOOM! magic happens.

--

at some point i'm gonna bother wiring it out (looking at around €10-30 for all parts) and making a ciruit to give to people like you, but i'm still too lazy

[TheNuzziNuzz]

I actually tried to do this with one white LED with a Snap Circuits potentiometer, and it actually allowed me to vary its brightness. I don't know if that will also apply to the LED strips, but it did work. I wanted to keep it very simple, and analog. I was also planning on trying to find a Wifi led controller in addition to this. I morso doing this electrical project for the experience. But i also just think it's cool to have something like that, even cooler to have made it yourself.

[WEEEEEE]

As far as the faders go, they seem to just be slide potentiometers (though for whatever reason they are way more expensive than regular slide pots). So you could just hook them up to an arduino's analogue input, and use that to control the brightness via a PWM signal that goes through a MOSFET.

That being said, an arduino is totally overkill for this, so something like a 555 timer might be better... though that may be kinda difficult.

OP most likely can't connect the slider pot/fader directly in series, that would probably dissipate to much heat.

20 minutes ago, Hackentosher said:

Are you dealing with addressable leds or the ones with individual wires for r, giving, and b? You could probably setup an if else statement with the sliders and each pin on the strips. 

Sounds like some basic common anode LED strips from the description.

6 minutes ago, manikyath said:

the issue here is most LED strips...

-snip-

Problem with using such a device is those tiny on board transistors don't look like they can handle 2.5A. 

[manikyath]

1 minute ago, TheNuzziNuzz said:

I actually tried to do this with one white LED with a Snap Circuits potentiometer, and it actually allowed me to vary its brightness. I don't know if that will also apply to the LED strips, but it did work. I wanted to keep it very simple, and analog. I was also planning on trying to find a Wifi led controller in addition to this. I morso doing this electrical project for the experience. But i also just think it's cool to have something like that, even cooler to have made it yourself.

as long as you dont overload the circuitry, in effect, an LED strip is just the same as a very power hungry LED.

[TheNuzziNuzz]

2 minutes ago, WEEEEEE said:

As far as the faders go, they seem to just be slide potentiometers (though for whatever reason they are way more expensive than regular slide pots). So you could just hook them up to an arduino's analogue input, and use that to control the brightness via a PWM signal that goes through a MOSFET.

That being said, an arduino is totally overkill for this, so something like a 555 timer might be better... though that may be kinda difficult.

OP most likely can't connect the slider pot/fader directly in series, that would probably dissipate to much heat.

Sounds like some basic common anode LED strips from the description.

Problem with using such a device is those tiny on board transistors don't look like they can handle 2.5A. 

 

Your talking over my head.

 

I'm looking for 3 faders on amazon that I can hook up to control the brightness of effectively 3 super power hungry led's.

 

This is my first real electronic project, I'm not looking to get into Arduino programming, and advanced circuits. I just barely understand what a resistor does.

[WEEEEEE]

Actually I just remembered that I once saw these used in a DIYPerks video:

http://www.ebay.com/itm/172055327012?rmvSB=true or http://a.co/fB36KuI

Basically these were originally meant to control the speed of DC motors, however they can be repurposed to handle LED's as well. If you replace the onboard potentiometer (the dial), and instead hook up your faders, then that should be able to dim the LEDs.

[manikyath]

Just now, WEEEEEE said:

Problem with using such a device is those tiny on board transistors don't look like they can handle 2.5A. 

well.. i havent looked up the model numbers of the transistors in my chinese 60 watt RGB controller (no kidding they'll claim anything these days.) but they barely look like they'd drive a single LED.

 

but yeah, i'd probably transistor out from the board's circuitry to a high power line to be safe.

[TheNuzziNuzz]

3 minutes ago, WEEEEEE said:

Actually I just remembered that I once saw these used in a DIYPerks video:

http://www.ebay.com/itm/172055327012?rmvSB=true or http://a.co/fB36KuI

Basically these were originally meant to control the speed of DC motors, however they can be repurposed to handle LED's as well. If you replace the onboard potentiometer (the dial), and instead hook up your faders, then that should be able to dim the LEDs.

 

2

Like I said, i am limited. I wouldn't know where to begin with that. I lost you at the bolded text above.

 

Also, its only rated for 3v

[manikyath]

1 minute ago, WEEEEEE said:

a DIYPerks video

just wanna mention this briefly:

 

DIYperks is an amazing guy for getting creative ideas, but dude has no idea what he's on about most of the time.

[TheNuzziNuzz]

Is there not just a simple dimmer switch that can do this?

[manikyath]

11 minutes ago, TheNuzziNuzz said:

Is there not just a simple dimmer switch that can do this?

chinese RGB LED controllers?

 

EDIT: actually, the *old* NZXT hue, like, before the hue+ thing happened.

[hambobolubia]

34 minutes ago, TheNuzziNuzz said:

Is there not just a simple dimmer switch that can do this?

a simple dimmer (like the kind for mains lights) uses a circuit that essentially chops up an AC wave form so it would not work for your DC without doing some custom stuff. another simple slider (like those found on audio devices) are variable resistors witch would work for 1 or 2 leds (20-40mA)but in your case you need to control 7.5A so at low lighting levels (essentially off) that resistor would be dissipating about 90 watts (a typical resistor can handle about 1/4 of a watt)   

[TheNuzziNuzz]

41 minutes ago, manikyath said:

chinese RGB LED controllers?

 

EDIT: actually, the *old* NZXT hue, like, before the hue+ thing happened.

 

Exactly, just with more LED's!!!

[hambobolubia]

Just now, TheNuzziNuzz said:

-snip-

i think a fun project for you would be to use 3 555 timers to control 3 transistors (might have to be MOSFETS at this current load) then you can use the sliders to control the 555. iv got nothing to do tonight i could do up a schematic if you want. 

[manikyath]

36 minutes ago, hambobolubia said:

i think a fun project for you would be to use 3 555 timers to control 3 transistors (might have to be MOSFETS at this current load) then you can use the sliders to control the 555. iv got nothing to do tonight i could do up a schematic if you want. 

i'd say just cut out the 555 timer all together, all you really need is a very fast blink of "#GoodEnough" accuracy that's somehow adjustable with a potentiometer.

 

if you wanna go fancy, you could get a cheap microcontroller (dont do this with a standard issue arduino, that's a waste of money, get a chinese ripoff at least ) that just reads out the value of a potentiometer and PWM's accordingly, if you add a few buttons and get creative with programming you could even build in lighting modes or memory for preset colors. then just hook up some mosfets for the output and you're good to go.

 

in fact, the chinese RGB controllers are exactly that: they're a generic 8-pin microcontroller that's preprogrammed with some flashy modes to make the spec sheet look cool.

[W-L]

3 hours ago, TheNuzziNuzz said:

-SNIP-

If you want full manual control you can get a 3 channel controller which will individually control the Red, Green and Blue chips like the old NZXT Hue. 

https://www.superbrightleds.com/moreinfo/rgb-dimmer-switches/ldk-rgb3-three-color-rgb-led-dimmer/117/526/

[TheNuzziNuzz]

6 hours ago, W-L said:

If you want full manual control you can get a 3 channel controller which will individually control the Red, Green and Blue chips like the old NZXT Hue. 

https://www.superbrightleds.com/moreinfo/rgb-dimmer-switches/ldk-rgb3-three-color-rgb-led-dimmer/117/526/

 

YES thats exactly what im looking for. I wish they were sliders, but thats the idea.

[TheNuzziNuzz]

Its not quite what I wan't but is it possible to use a simple program to control the leds from a computer via a USB port? Then find cheap HID sliders and map them to control the colors?

[hambobolubia]

I would get the thing with the knobs and remove the knobs replace them with a equivalent sliders fairly easy mod made 3dprint a encloser and your done

[TheNuzziNuzz]

11 minutes ago, hambobolubia said:

I would get the thing with the knobs and remove the knobs replace them with a equivalent sliders fairly easy mod made 3dprint a encloser and your done

Not everyone has a 3d printer in their closet, so that makes it more difficult, but I will make an enclosure from like wood or something.

 

I have no idea where to begin with replacing the nobs with sliders.