Need help with extremely complicated ws2812b strips project!

Projects
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Hello everyone,

I have been reading through this thread and would like to address some of the discourse taking place. While most of it has been helpful and kind, there have been multiple instances of “unsportsmanlike conduct”, for lack of a better term.

Our forums guidelines outline the expectations held of each and every user. I’d like to bring attention to a specific heading:

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There’s nothing wrong with disagreeing, as long as you remain respectful. I appreciate that the vast majority of these posts have been constructive. Our forum is a place for makers of all backgrounds and expertise to come together to help each other, make cool stuff, and have fun. There is no place in our community for disrespect.

I’m glad to see that the discussion has “reset” to an extent and is now once again heading in the right direction. If the conversation deteriorates once more we will likely lock the thread.

Thanks everyone, good luck on this project, and happy making!
Zach
Technician | Core Electronics

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Then you’ll never understand. You’ll never get an idea of what exactly I’m trying to get to, how it shows (visuals) and you knowing less of the project and how it functions and it would only lead to more misunderstanding and confusion. A video that lasts nearly 5 minutes to show you exactly the results I’m aiming for and you choosing not to see something that I can’t put into words isn’t going to get us anywhere.

The power of each LED strip is 43.2Watts, which is 8640mAh. Tell me which 18650 batteries can match that power capacity.

That’s exactly my statement, thank you for re-confirming it. If the LEDs don’t lit up for brief instances yet are powered on, the powerbank detects that as an off mode and would need to be manually switched on again. That’s what I was talking about.

Well, here is another recommendation. I would look further into this. Thanks for confirming.

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Thank you. Now I’ll fill you in the info:

The measurement from the tip of sleeve to the base/bottom of the jacket is measured at exactly 1m. So if we use two 144LEDs per metre strip (exactly no trimming the size of the strip) for the left and right sides, it should fit to scale.

Now when measuring the length of pants, from top to bottom is at 92cm. So roughly 8cm less of the 144LEDs strip. But I’ll try my best to calculate:

Each diode is 3.65mm (0.00365 meters)
One ws2812b 144LEDs strip by default is 1 meters and we only need two 92 cm/0.92 m of the strips. My maths isn’t that quick so probably would give you a headstart.

The jacket would more than likely have no need to separate into 2 segments as it depends on the flexibility and position of the LED strip, as it’s perpendicular flexibility is different to the pants (which when bending the physical pressure affects the structure and thus the durability of the LED strip). The pants are more likely to be divided into 2 segments since the bending angle at the kneecap can be very acute.

We’ll focus on just the jacket and pants for now, but if you have no issues with adding on the glove, then read on:

Since the glove isn’t requiring more LEDs unlike the rest of the outfit and is using a slightly different LED strip, in this case 60 LEDs per meter, we would measure the hand vigorously coming down to the following measurements:

Length of hand/index finger: 18.94cm
Diameter of hand (middle of palm): roughly 10cm
Fingers of the hand (from tip of finger to base of palm): thumb - 12cm
Index - 17.5cm
Middle - 18.94cm
Pinky - 14cm

Hope its more than enough info, let me know if you need any more. :+1:

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You have provided enough description so that I understand what you are trying to do in sufficient detail to see that you are going about it the wrong way.

For instance, the figure you have quoted for your required power assumes that your ‘effect’ is to have all the LEDs at bright white all the time. That does not agree with your original description of the project: “…effects such as fading/glowing/shimmering, movement-like animations, wipe-effects, etc.” You can’t do that with solid bright white - you need to use colours. Once you use colours your current requirement drops. For instance, if you use only red or green or blue then you will require about one third of the figure you have calculated. Most other colours will be similar, and if they aren’t then it is possible that you will adjust them anyway to achieve a consistent level of brightness along the strip, because the effects require that consistency in order to look good.

Your calculation of required battery size might be technically correct, but it doesn’t apply to your particular implementation. And to make that assessment all I have to know is that you are intending to have effects other than a solid bright white.

Your power requirement is going to affect the number and size of batteries, the layout of the wiring, the wiring sizes, the heat you will need to dissipate and so on - important basic design questions.

That’s why I keep saying that until you construct a sample strip, build some effects that match what you are looking to achieve and actually test that sample, you can’t make the decisions that you need in order to start building.

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Jeff, to be fair, this would have been my starting position! So that one is on me.

My view is that you start with the “max” or worst case; if that is easy to do, then do that as you will have 0 issues.
If that is out of reach, then wind back via acceptable “cuts” in the needs.

If, at any point you want every led to be on white, even for a short period of time, then the power supply and wiring needs to support it. But if that is never the case, then that is an acceptable cut back (as you say) to reduce the actual power needed. If you want every LED to be on white at the same time, but the power cant keep up, then the net result will be dimming and potentially some LEDs not even turning on.
So to start simple, It would have been my point to work out max power needs, as a starting position just to keep things moving.

Edit:
I think this seems like a good overview and worth a read.

It covers lots of things everyone have been talking about.
i.e. how they worked out max power needs, then comments on how, with cleaver programming you can reduce that need.

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That’s not unreasonable, but OP has already stated that they will be using effects, so while all bright white could be worst case as far as instantaneous current is concerned, it is not applicable in considering battery capacity requirement. That worst case is relevant to battery/adapter maximum current capability and (to some extent) to wiring gauge and lengths. But the point is still the same (and reinforced by the article you reference): until OP has an actual example in front of them to look at and measure, everything is just conjecture.

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Where did I mentioned that? If you refuse to understand by even not watching the video to get an idea, you actually are jumping into assumptions.

Good day.

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Can we please go back to the simplicity of the lengths, amount and density of strips like before instead of taking sides and defending others? I hoped that people actually have a bit more open-minded approach for a beginner instead of just telling them what they did wrong but not filling in what is the best solution with minimal risks and less setbacks?

I appreciate the input but I feel if we can’t do things one at a time without suddenly defending someone else’s criticisms then we aren’t giving each other an easy go.

Please return to reading thru my answer for measurements requirements and provide the relevant answers so we can get thru this one at a time, or else have a good day

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The full quote is "For instance, the figure you have quoted for your required power assumes that your ‘effect’ is to have all the LEDs at bright white all the time. " I am not claiming that you ever mentioned that’s what your effect would be, but rather that in doing your calculation for the battery power needed you have assumed that’s what it would be. That statement is correct - you have used a figure of 50mA per LED, which is full bright white. Based on your description of what you want to do I believe that you will actually be using colours (including white). That means your calculation of the power required in the batteries is higher than you actually require. It also means that it is not possible to calculate ahead of time what power you actually need, because the effects you will use have not been coded yet. It’s possible to make some guesses, or to build for worst possible case, but it would be preferable if you set up an example and did actual measurements.

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There you go. Absolute ignorance. Each LED on any of thise strips supplies 0.3 watts, equivalent to 60 mAh, not 50.

Full white is when I use those colors as an animation preset, but NONE of my animation presets use all LEDs at 100% brightness and that all LEDs are all white at any given time.

Please do me a favour, spare yourself of this staunch approach and be like Michael, focusing on 1 aspect at a time to know where to go from the start. FOR A BEGINNER.

I’ll prefer not to argue over this 100% bright white for all LEDs again, so if you can’t come up with anything more realistic then I bid you good day.

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60mA is the figure that Adafruit uses, but the spec sheet says 16mA per LED or 48mA per device. There are likely differences between different manufacturers: the usual figure that is used is 50mA. But the difference is moot - whether you are using 48mA, 50mA or 60mA you are overestimating the battery power needed for your particular application. By how much? That’s impossible to know without knowing what your effects require, but they don’t exist yet. We can guess, but would that be any better than your own guess? We can calculate worst case - that will work, but it will likely lead to a design that is much larger and more expensive than you really need. Why not just make the example up and test it? You will get a result that is not only reliable but if that result turns out to be impractical or too expensive you can adjust things to find an arrangement that makes the project practical and affordable.

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If you can’t do it like Michael here does, which is one step at a time, simple info to get a head start, in this case the size, density and amount of LEDs, then we are stuck in this circle of “depends on” or “whether or not” which can result in numerous, unrealistic answers/results which is a guessing/experimenting cycle.

Refer back to the 2nd last post I replied to Michael for size, density, length measurements of the LED strips.

The most basic, essential parts I need to know is:

• what AWG wire size should I use? Say if others stated that size 18 is ideal due to optimisation and better robustness, and that LED strips don’t need to withstand that many Amps, can that claim be true, and you agree it’s the best size to test on ESP32-S3 or any ESP module? Without any power source for now?

•Others also added that small power banks deliver around 3-4amps at 5V and can come with form factors that is considerably compact and miniscule. I know that you mentioned numerously that regardless of capacity they are not ideal for PSU (unless a KeepAlive module is hooked onto it), that either Lipo batteries or 18650 battery packs with a voltage booster to get to DC 5V is sufficient. Either confirm or disagree with those other experts’ statements is credible.

•would battery packs support AAA or AA batteries rather than 18650 batteries deliver adequate power?

•A diagram of how the arrangement can be done. Eg. One PSU powering the LEDs strip thru the power wires, and a lesser-capacity PSU powering the MCU, but both the DATA and GNIO wires are connected together between the MCU and the LED strips.

There, those 3 queries to get me started. I’ll test the software/programs/apps once I have the necessary AWG wires.

The power details are also in the previous comments (see above).

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You have three sizes to consider - ESP power, Signal, and LED power. AWG18 is a good general purpose size for ESP power, but AWG20 would work just fine. Signal could be same or smaller, but size might be based on the routing necessary and the strains it will be subject to. It’s the LED power that depends most on the current. Your calculation of 144 LEDs at 60mA per LED requires AWG14 for a 1m run, but my claim is that you will actually need much less than that, so AWG16 would likely work. The link that connects ESP power ground to LED power Ground (if you need it) would be fine at AWG18 or AWG20. Of course, the final version could have runs for LED power longer than the 1m I have assumed for the prototype, requiring heavier wire, but you won’t know that until you have determined the number of batteries and the layout.

Don’t use a power bank - it will only cause trouble and in any case is unlikely to provide the current that the LEDs require. Use a battery bank with a battery voltage of ~8V - for example two or more LiPo such as 18650. It will need a regulator to provide 5V. Make sure the regulator is rated to power the LED strip - the regulator will likely be rated much lower than the battery maximum discharge rate. You will find, however, that the price of the unit goes up considerably as the current requirement increases - that’s why knowing ahead of time just what maximum current you require is so important. But for the case you have mentioned you will need to power one strip. If you are using a ESP with a 3.3V regulator on board then you can power that from the same 5V output of the battery bank, but a nicer option would be a battery bank that has a separate low current 5V or 3.3V regulator built in. What is sufficient in terms of mAh capacity depends on how long it needs to run for - the calculation has been mentioned above.

The wiring doesn’t change much if it’s one PS or two.

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Note that for your prototype you can use the PC USB power as the ‘low capacity battery bank’, simplifying the initial setup. But you still need the ground connection between the two power sources.

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So AWG 18-20 for ESP32 power/MCU connection, assuming a different size for Data and Ground?

So AWG 16 for direct connection between the PSU and the LED strip?

I’m taking that on the less-risky/most effective side, I need both AWG 20 and AWG 16 wires?

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So AWG 18-20 for ESP32 power/MCU connection, assuming a different size for Data and Ground?

So AWG 16 for direct connection between the PSU and the LED strip?

I’m taking that on the less-risky/most effective side, I need both AWG 20 and AWG 16 wires?

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So it’s better to have 2 sizes of AWG (16 & 20) rather than either 16 or 20 to cater to voltage requirements for the PSU and MCU?

Also since JST SM 3 pin LED connections cable size is AWG 22, is it wise to use hookup cables with the same AWG size? Or still use whichever size you recommend to be on the safe side?

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It depends on what you mean by ‘better’. It might be cheaper to go with just the one big wire size, because you would buy just one big spool. It doesn’t provide any advantage with things like voltage drop and wire heating. It might be better for pushing leads through seams in the clothing, if that’s needed. It might be better for durability, but likely worse for flexibility. It could be either easier or more difficult for soldering, particularly to small components. In short, it depends. Try it and see.

You have the link to the wire size calculator - fiddle with the numbers and see what the effects on things like voltage drop and dissipation are with different wire sizes. Then look at the wire prices in the shops and check against your budget. Then make a decision. It’s your project.

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Then again, I would want to be on the safe side and not risk a electrical fault. Given the size of the tabs on a ws2812b and the best size that not only fits the tabs and is flexible (especially if this is wearables-related and wires can again be resoldered) but also is low-risk/non/less-fault I think you know better.

Even if this is my project, I am no expert and leaving the wire parameters for endless pondering makes me concerned in increasing the budget and experimenting on more wires increases the expenses and resources wasted. I’ve worked on things and left myself to decide on the components with minimal queries and massive research attempts have led to the failures that ended up as results. I can’t risk another waste of costs and resources to attempt something that leaves me with without expert advice and more failures that can’t be reverted and resources that cannot be used/reused further. So take this as me relying on the best advice before attempting to risk/make it work than have endless experimenting that gets me nowhere and piling up on unused resources. I’ve been there already and will not repeat that again.

Just please tell me the best AWG size. Just one number. That’s all I ask. And provide the reason why it is preferable for ws2812b strips with DC 5V and 43.2 Watts.

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There is no single best. There is not just one number. You have been provided with suggestions (in many cases based on actual experience) that would cover most situations adequately. But with the variables involved - current, length, acceptable voltage drop, acceptable heat dissipation and so on - you have to make the decision. If it turns out to be wrong, change it. That’s what project development is all about. Don’t get bogged down in endless pondering - make a decision, accept that it has compromises, go ahead and start building, and change things if you think it could be done better.

2 Likes
104

The Seeed Studio XIAO ESP32-S3 doesn’t get detected even after flashing the WLED software onto the microcontroller. The WLED app requires that microcontroller (when connected to an LED strip) be provided/linked to an IP Address or URL which is nowhere to be found. Assuming that can be obtained when flashing the WLED software onto the ESP32-S3, it apparently doesn’t have the supposed option to enter wifi SSID login details so that the WLED app can detect it’s presence. Yes, I have done all suggested steps such as pressing on the boot mini-button and then releasing it once its connected to a PC, installed necessary drivers for the microcontroller to be verified, flashed different boards/software versions (4/8/16MB flash, with/without OPI, etc.) but so far all efforts have been futile. Does Seeed Studio XIAO ESP32-S3 module come included with its own built-in IP address or URL? Or it can only be configured after flashing the correct software?