Hi all, i am not new to led but new to wled.
I have a question which i only found a little similar to mine but not the same.
I have a controller board which is builded up the way that it has only 1 available data pin.
So befor i try it and perhaps get something damaged, i want to ask you, if it is possible to connect to strips to the same data pin? And what happens than with the controlling?
Will i be able to define those two as two segemnts, or will they always only work parallel?
Or perhaps didnt work at all?
The place where i want to install it didnt allow me to connect the second strip at the end of the first one and therefor i am asking this question.
If you flipped the LED strips around and told WLED they are “reversed”, you can get the head and tail of the 2 strips close to each other so you can daisy-chain the data signal from the end of strip 1 to the start of strip 2.
To answer your posted questions, yes, if both strips are connected to the same data pin, they will act exactly the same. In some situations, that’s actually desirable. Usually though it’s not which I suspect is your case.
You only need one wire from the tail of strip 1 to the head of strip 2. If it’s large enough, the voltage drop should be minimal and you can still daisy-chain the data signal between strips that way.
Thanks a lot. Sure if they act the same it makes no sense for my usecase. You always connect the end of strip 1 to the Start of strip 2. What Do you mean by flipping them both. Do you mean connect the Controller to the end of strip 1 so that the arrows showing in the wrong direction. And solder on the same point wehre you solder the data cable from the Controller to strip 1, also a data cable to strip 2? Or did i misunderstood your recommendation? Thanks again!
Let’s say you have strip 1 & 2 laid out like this:
STRIP 1 STRIP 2
WLED ESP |o----o| DATA IN : LEDs : DATA OUT |o----o| DATA IN : LEDs : DATA OUT |o
This is ideal and makes it easy.
However, if it’s like this:
STRIP 1 STRIP 2
DATA OUT : LEDs : DATA IN |o o| DATA IN : LEDs : DATA OUT |o
Where do you put WLED ESP controller? If you put it in the middle, you get a mirror entry left and right of the center where WLED connects.
If you reverse the direction of strip 1 or strip 2, things get easier. Let’s reverse strip 2 direction:
STRIP 1 STRIP 2
DATA OUT : LEDs : DATA IN |o o| DATA OUT : LEDs : DATA IN |o
Now WLED gets connected to strip 2 for end, and data out of strip 2 feeds strip 1. However, this entire thing is visually unsettling because now everything is right to left where WLED is configured by default as left to right. If you want the visual default behavior with reverse ordering, you can simply configure WLED to reverse effect direction and match the “Peek” view to the actual view.
Thanks alot. IT makes me smarter but the last solution is not beneficial because IT still connected one strip after the other. So if i want to have 2 stripe connected to the Controller directly i need a Controller with more than one data pin or i live with the mirroring.
Thank you
With the 2 strips meeting at a T, you can choose to place the wled controller at the input end either strip, swapping around physical orientation so the 2 strips meet so the data signal gets passed on.
Otherwise I recommend running a single wire from the end of the first strip back to the start so it can connect to the input data line on the second strip.
The mirror effect while nice for some things will cause you to have lower WAF/GAF/NeighborAdmirationFactor
Are you Sure with ging back to Start? Because this means in most cases more than 50cm distance and i read in many Websites that you should not have distance between Controller and LED and between LEDs more than 50 cm…
Once you are connected to the first strip, the voltage coming out is 5V, not 3.3V like coming out of the controller. That gives you a few meters of forgiveness. Using a larger data wire adds a few more meters of forgiveness. Make sense?
I use 2,5mm" , shoudl be large enough, i was not aware that out of the data pin also full power is coming out. why is the voltage hiher after the first led as directly out of the controller?
Strip1 would get the data signal from the d1 mini routed to the other end of the strip. A very long wire. I recommend against that method. In this specific layout, I would wire from d1 mini to strip 2 data in, strip 2 data out to strip 1 data in.
hi there
i might also try to solve this problem :
how many strips per data output esp 8266 was the question .
esp is running on 3,3v this is enough voltage to drive direktly a ws281x whith a quiet short datacable .
maybe it is enough to drive 2 led strips but both strips have to follow the data direction ( or simply connect them to data in = DI
NOT to DO
dependig to ws281x they like 5v for data in but it also runs on 3,3v whith short data cable
dependig to esp8266 the output current is limited (30ma i think ) so 2 strips may consume to much ma so the voltage drops and data transfer will not work or esp blow up ( expensive smoke )
but there is a little dirty trick
connect the second strip to the output from strip1 led 1
u loose the first led on strip one but all leds behind led 1 strip 1 show the same
( in wled u can skip led1 But i never tried this because i always have strips whith max 300 leds per data out put from esp )
the voltage question :
the ws281x works like a level shifter an can drive at least 3 strips in paralell from DO data out
next dirty trick u solder direkly to ur w1 module there are more outputs ur breakout does not support
then u have enough outputs ( maybe) i think at least 8
what i do:
i run long led strips up to 300 per line
and i define them in wled to segments
this is the most flexible and effective way to do it for design and proramming
ok and i want to set some things correct
1 about data line
the data cable should be a thin cable
a 2,5mm cable acts like a condensator which will make the data signal more round which looks more like sine than a square ws281x does not accepts sine signals
and 2,5mm for data is not needed because there is no real current consumption its only a data signal
use 2,5mm for connecting to the powersource
for data it shoulb be 0,22mm
it schould be sielded like a microphone cable or a cat6 cable
that imroves the foregivnes for long data cables
also using a levelshifter 3,3v>>>>5v will improve the data quality and will make the data mote stable
the frequency for transferring data is between 400 and 800 mhz THAT IS A FREQUENCY USED FOR RADIO TRANSMISSION and is used for mobilefone communication ( in europe )
so shielding of ur data cable is a little usefull ( most important )
data direktion
ws281x has a data input which only understands input signals
this inputsignal is processed and the ws281x eliminates the data itself is showing and only transmits the rest of the data for the following leds
cause it is processed there is a definite data output which can only send data and not recive any data
ws281x is a data oneway road ONEWAY OOOOOOOOOOOOONWAY
so it will not work equal how long u try to show something whith ur leds
watch data direktion ! ( rule nr1 in serialdatasystems )
what i do for use for data cables
MICROFONE CABLE Good quality and a very good schield ( max 2 datalines)
or data cable like cat6 ( max 16 datalines)
other than with audio signals it dies not matter if the cable is shielded like a microphone cable - it’s all about the physical resistance.
So: then thicker the cable the lower the voltage drop. 0,75 mm² is good enough for supplying 5V over 5m distance.
If the first strip is too long away from the D1-mini (too long = more than 1m) then I would recommend using a level shifter from 3.3 to 5V (e.g. 74AHCT245) - with thus the first strip can be 5m away.
Hi @Def3nder
Thanks, just to prevent missunderstanding.
We Are talking about the data line regarding the microfone cable Not the Power cable.
IT is confusing how mich different opinions i found.
The guy where i bought the Controller Board says 50 60 cm between Controller and strip or between Strips should be the possible maximum. Even if his Board has a levelshifter. Longer distance will lead to not exact colors.
On another Homepage i found for distance like you said a Range extender is needed 5 Meter.
Gerrit42 above said as bigger the data cable as worse the data quality =rounded Signal.
You said of i understood IT correct, bigger cable is better because voltage drop, but is voltage drop relevant vor data cable?
Hmmm - “not exact colors” cannot be true because it’s all digital.
I personally have about 10 WLED instances up and running: with and without levelshifter and with the ESP near by the strip (20 cm) or far away (1m without levelshifter).
TLDR: thick cables are good.
Long version:
The only problem us the voltage drop.
And this is simple physics: the bigger the diameter of the cable, the lesser the resistance and with a constant current the lesser the voltage drop.
This has different influences for the Data line or the power lines: when the voltage on the data line is too big, the signal cannot be interpreted in the WS280x and it doesn’t work correctly.
Other for the power lines: if the voltage drop is too big it does display dimmed colors correctly but the lighter the LED and the more white is shines the bigger is the effect on the brightness/color - white becomes more and more yellowish.
So I recommend to use 0,75 mm² cables for the power lines and inject power every 4 meters (max. every 5 meters).
Same for the Data line: if you need to have a distance more than 1m without a levelshifter, use a 2 mm² and you can go far beyond the 1m. Or use a levelshifter and you can stay at 0,75 mm².
…one thing about ‘shielded cables’ (like microphone cable): I had quite disturbing random pixels being lit at the beginning of the strip while it was turned of. Turned of does mean the Data signal tells the LEDs to not display anything, however, the qhole strip has 5V power all the time.
With a lot of WLAN signals ‘flying around’ and a 5m ‘Antenna’ the will be some kind of signal interpreted as ‘turn the LED on’ and because the WS280x work with shift rehisters only the first few LEDs will do this.
I thought using a shielded cable from the D1-mini to the strip (for the Data line) could solve the issues but it did not help at all - the ‘wrong signal’ is introduced from the long LED strip rather from the Data line.
The solution is to use a relay attached to PIN12 that will turn-off the power when brightness is zero.
I think with Level shifter etc i am here on a save Position and i also have 2,5 and 0,75 cables for soldering. Perhaps using 2,5 for Power and 0.75 for data. I Was Not Sure, Important is a save solution and nothing gets Hot and burnin.
Even if i am not Sure if it will be easy to solider 2,5 mm cables on the small cuper contacst on the LED Strips
first of all there was a mistake by me ws281x Datatransferspeed 400Khz and 800Khz NOT MHZ so radio frequencies do not matter so much
the experience as sound engineer whith micrphonecables is:
that i can transfer digital data ( spdif ) over a simple good quality micropfone cable. it is able to transfer data about 10 meters and even more
i think your colour mismatch is caused by undervoltage at the power bus not at data bus
its simple because there is a decoder inside your ws281x which controls the 3 led inside and manages the data and every ws281x has its own controller
so the controller always transduces 24 bit to 3x8bit colour but if the power which is needed is not provided by the powersupply or the distance is too big u will see diferrent colours on the same strip
( the first led works fine and number 300 is bad thats caused by voltage drop over distance )
and if the undervoltage is dramatic also the controllers cant work correctly and funny things happen
to prevent that u can use more power input points on the strip whith the thick cables
to go to detail Dataline
Dataline recommondations are for transmitting a rectangle signal in dc that means 0= 0v 1=+5V @400-800 kHz
But ONLY whith 0.003 Ampere
for that we need no thick cable
Thick cables will flatten the recktangle signal and make it look more like a sinus
ws281x need rectangular data
thin cables supports the data signal ( have in mind your cat5 internetcable its 8 thin data lines and no shielding )
The microphone cable is shielded and the schield is recomended to be earthed ( simply connect to Minus )
that coveres the data line from Distorsion from outside signals
in praktice
trail and error
just try and find out
power the strips whith propper powersupply !
means 0.05mA x numbrer of leds + 500mA for the controller . thats the power u need
0.05 x 143 led + 500mA = 7650 mA
also inject power at multiple points on your strip
and if possible in the middle of your strip or on both ends
use the right diameteres matching your power needs
for calculating i normally use the " victron toolkit" from any appstore its free
Things to know
led have different colours and there for diferrent voltages they need to light up
also in ws 281x
blue is about 3,2v green about 2,4 and red around 1,8v
the light emmitting diode does need the specific start voltage because its a diode
diodes have a breakthough voltage that they become conductive and start to light up
the colour in ws281x is controlled by timing and not by led voltage
and at 5 v all 3 leds in the ws281x work correct
so calculate a voltagedrop of 1% for your main power line
if distance to power supply is the problem
think about changing to ws28xx whith 12v
And always solder verry carefully and clean ( extremly on Data ) to prevent shortcuts or cold soldering
Expensive smoke
if u overdrive the data input of ws281x u just kill it
but the last solution is not beneficial because IT still connected one strip after the other. So if i want to have 2 stripe connected to the Controller directly i need a Controller with more than one data pin or i live with the mirroring.