LED strips for dummies

Hi folks,

Got a new feature request from the wife today: she wants multiple LED-strips in our house. Each LED strip needs to be controlled separately, which means ON/OFF and adjusting the colors (i.e. all LEDs the same color).

Don't know much about LED-strips, so read quickly about it today. I think I need RGBW, since we are more the warm-white kind of people...

Lot of resources point to this tutorial, which is based on the ws2812b strips. The physical wiring seems to be very straightforward, but I see this quote:

The WS2812B data pin should be controlled by the Pi’s GPIO18, because that’s the GPIO used by the neopixel node.

Does this mean that I can only wire and control only one LED strip with my Raspberry and the neopixel node? I had expected that I could use one of those neopixel nodes for each LED strip. Or is this setup perhaps not the best one for my needs? Or can the GPIO from my Raspberry not deliver enough power for multiple strips? Or ... :exploding_head:

And are there other practical tips, that I need to take into account? Like e.g. the number of LEDs per meter, the maximum length of the strips, the maximum distance between my Raspberry and the strips, and so on?

Thanks for extending my marriage (with at least a month or two ...)!
Bart

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A ledstrip will require separate power if you want to connect many leds (50 mA per neopixel).
And you want more than 1 ledstrip.

Easier "solution" is a esp8266 with a separate powersupply, or even easier, a milight controller.
For mi-light there is hub software (github) available so that you can control the controllers from a single source.

First of all: How did you do that? :see_no_evil: :face_with_monocle:
I have to convince MY wife, that "this or that new feature" is a must-have in our house! :rofl:

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Have not thought about that today...
I assume it must be a very small distortion in her DNA string :rofl:

Ok, thanks for the confirmation (and the current value)!
And I see now at this link that the LEDs at the end of the strip might have other colors due to the voltage drop:

image

The main problem is that I then have to start learning how the esp8266 works, and I don't even have time to read a CSS book to understand your tutorial from yesterday :wink:
But that might have been a good solution...

I have that name seen passing by a couple of times, but never looked it up ...
So a milight controller is a WIFI based LED strip controller:

image

But of course then I need also an extra power supply. And it looks like you need a milight LED strip, not another one?

Yes you need a power supply.

mi-light controllers come in (many) different flavors depending on the ledstrips you need a specific one (and one per strip), but are reasonably cheap. What you do need however, is something to control those controllers, either a remote and/or as we are node-red fans, something that we can use with node-red, which is another box that acts like a hub/bridge. This can also be a esp8266, but there are other solutions available too (look at milight ibox) which can be used with the node-red-milight-2 node.

sidenote - i find hue led strips easier to deal with, yes they are more expensive and are not neopixels, but still.

Just about to go to bed but want to add Neopixel LED strips are not a good option if warm white will be the most used "color". I would look into RGB-CCT strips with RGB and adjustable white color temperature. I just installed a bunch of RGB-CCT Mi-Light 24V garden LED spots and I use the ESP8266 hub software already mentioned to automate them through MQTT. I would assume they also sell RGB-CCT controllers that can be used with strips from other manufacturers (I'm not a LED strip expert though).

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Try a Wemos D1 mini they are so simple to use, even I managed several projects with them!
From Ali Express (copies) are now about 2 euro.

Ah you can't send wifi commands directly to the controllers. That is a pity ... But thanks a lot for pointing that out!

That will indeed be the case...

I have a few wemos lying here somewhere, but my Node-RED todo list is sooooo long ...

Until now I have managed to do everything wired. Last year I have digged through my whole garden to put a large amount of water-resistant CAT cable under the ground. They don't call me the "cable guy" without reason :thinking:

In fact, I started today looking for a wired setup with cables from my Raspberry to the LED strips (which is physically possible), but I didn't find anything useful...

Ah you can't send wifi commands directly to the controllers. That is a pity ... But thanks a lot for pointing that out!

You will have to send the signal over a nRF24L01 via UDP (ibox is simpler which integrates via wifi but then again, china phone home), some weird protocol they use for it.

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Slight correction to this. I think they sell a wifi gateway for their products (which might or may not be easy to integrate to Node-RED) but the lights/controllers themselves use a proprietary 2.4GHz protocol for communication. The ESP8266 firmware requires a separate (cheap and common) 2.4GHz NRF24L01 radio module to communicate with them.

I also want to note that while the protocol used is proprietary to Mi-Light (not Zigbee based either) the products do relay the commands forward to next light/controller so your custom ESP8266 controller needs to only be close to a single light.

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This setup is really not very difficult. You'll only need a single ESP8266 to hook up to the radio module with some dupont wires (if soldering is not your thing), flash the firmware over USB and then it's mostly configuration.

As a bonus Mi-Light sells great low price wall switches and remote controllers you can both directly link to the lights/controllers but also snoop by the ESP8266 firmware to do whatever. For example I set up 8 garden LED's to 4 groups/channels and with their FUT089 (or B8) remote I've got 4 more channels to play with. One went to control LIFX porch lights and another to toggle on/off 15y old 12V pathway LED's I retrofitted with some relays this summer. :slightly_smiling_face:

A couple of days ago I watched that video: https://www.youtube.com/watch?v=B8DQntdtD4E
I think it gives yo a fairly good summary on how things can be done.
GV

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To summarise the topic so far - choosing and setting up LED strips can be confusing as there's so many ways to do it. I suggest to invest some time understanding the different options to find the solution (most likely) best for your needs and budget.

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He also has a very good video on how to choose between all the different LED strip types, which I found very useful - https://www.youtube.com/watch?v=QnvircC22hU

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Thus the shelly-rgbw2 is yet another option. Here no bridge is required and you can - from Node-RED - send http requests or MQTT messages straight to the shelly controller. From their website:

Or 4 single-color led strips:

image

And it allows even dimming via PWM. But it is more expensive ...

Yes will need to do. The forest is getting bigger ...
Weren't you going to sleep?

A big advantage is the voice control via Google Home/Alexa, although be minded that if you also want to use MQTT then voice control is disabled (you can't use both! either one or the other. BUT you can use their API for http requests instead).

Otherwise, a good choice.

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From what I see here, the Shelly might be a good option for me: I can setup something fairly quickly, and it can easily be integrated with Node-RED.

But two questions about the hardware part (in case of 4 single-color led strips):

image

  1. Would it be a problem if these wires (between shelly and the led strips) is longer for one of the LED strips? For example 15 meters... Because it is not clear to me whether this is a PWM signal or not?

  2. What would be the maximum length of each individual LED strip?

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Morning everybody,

Since you need always a power cable to the LED strips, a full wireless setup will be never possible. So I have been searching last night whether a full wired setup is possible. But of course you cannot send the PWM signals through your entire house, unless you want to have visit from the radiency police :wink:

Then I remembered that a colleague of mine is controlling all his LED strips via a Raspberry and the DMX protocol. As you can see on the readme page of the node-red-contrib-udmx node, this can be done with a 13 euro usb-to-dmx-adapter to send DMX messages through your house. At the location of the LED strip you need to use a dmx-to-rgbw-controller like this one on Aliexpress for 10 euro.

The setup would look like this (with a DMX cable running next to the power cable):

Which might also be a nice solution for this cable guy ...

  1. What would be the maximum length of each individual LED strip?

it depends on the type of leds and the led strip itself, there are strips with 30, 60 or even 96 leds per meter. You will see voltage drop after X many leds (meaning the end is dimmer than the start). When buying strips, they usually indicate how many watts per meter they consume.

An example of 96 per meter RGBWW - 24watt per meter, for 10 meters you need at least a 240watt powersupply (and add some overhead). With WS2812B 5050, you can run them on 5V, lower brightness and you need a power source every meter (because of the voltage drop)

There are so many variables in this realm, good luck :wink:

Damn yes, I also need to determine the number of LEDs per meter :woozy_face:

Thanks for reminding me :woozy_face:

In the current feature request, my lovely wife only wants to have about 5 LED strips of about 1,5 meter long. But I assume that - if the result is good looking - that she wants afterwards extra strips (e.g. in the kitchen) which will be much longer ...