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Pioerpaolo

Power supply unit

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Hi guys, as object, I wanted to know kindly, how to calculate the power of the power supply to add to the existing 1-8 Ch bank, to drive a chain of 340 pixel LEDs, having already the first power supply on the controller as described above, on first 8 channels of 150watts. I tried with 150 pixels and they light up perfectly, adding others, going on in the chain, the light fades, as already known. Do I have to add the missing power, calculating where a low light starts to come from? Type 4 chains of 50 pixels = 15watt x 4 = 60 watts ?? Maybe a 100 watts? Can you shame me? Thank you and sorry my English translated online.

 

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Strings of 100 nodes (12V) should work fine.  If you are running 5V, the WIRE will not support the current and you need to Power Inject   at the Mid point or the End. The Watts are not your problem if you math is correct.

C-----B-------M------E

C is controller

B is begin of string

M is Mid point (50,51)

E is the End of the string

Cut ONLY the + lead of the string at M if the power supply is NOT THE SAME as the controller to avoid clashes (Data and common MUST go thru)

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I use a lot of high power pixels in the string, so I ought to use power injection.

Usially i do power injection, like shown in the picture (it's an example for 150 pixels string with injection every 50 pixels) (red - (+), black - GND, green - DATA). There is one important thing in case of using different power supplies: the GND of all power supplies must be the common.

 

Pinj.png

Edited by Valentin

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therefore the auxiliary power supplies are in parallel,

how to calculate the power to add? I calculate the watts that it absorbs between M1 and M2, and so on? Example a string of 340 bulbs, 0.3watt bulb, which power I put on the controller and how much on the various M1, M2, M3, M4 .....

 

thhaks

 

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45 minutes ago, Pioerpaolo said:

therefore the auxiliary power supplies are in parallel,

how to calculate the power to add? I calculate the watts that it absorbs between M1 and M2, and so on? Example a string of 340 bulbs, 0.3watt bulb, which power I put on the controller and how much on the various M1, M2, M3, M4 .....

 

thhaks

 

No, they are not in parallel, because there are led strings between them.

In your case (340 bulbs):

0,3W*340 = 102W. Using a 80% rule, u should have 102/0,8=127,5W power supply (i don't counting the controller power, because it will be enough to feed it). U shouldn't make inparallel the (+) wires of power supplies (only the GND wires).

So, in case of 12V leds u shold inject a power every 100 leds, but in your case better to start from the 51st led, then 151, then 251, then 340.

I tryed to show that on the picture.

I think it's better to start from 51st to prevent the overloading of power slot of controller. In that situation the controller will power only about first 20-30 leds, but the main power load of the string will be on the additional power supplies.

To prevent cutting of string connectors i use triple-side connectors (3pin male - 2pin female - 3pin female). It makes power injection simpler.

Pinj.png

Edited by Valentin
lang

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I your picture I'm hoping it's all the same power supply and not multiple.  If you are using multiple power supplies DO NOT connect the V+ together, just the V-.

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59 minutes ago, Little_b said:

I your picture I'm hoping it's all the same power supply and not multiple.  If you are using multiple power supplies DO NOT connect the V+ together, just the V-.

in my picture are different power supplies. Power injection with one power supply it's very simple thing. And of course u shouldn't connect V+ together directly, but u can connect it through the led string.

I have some more drawings with 4 power supplies for better understanding what i mean.

 

Edited by Valentin

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18 minutes ago, Valentin said:

in my picture are different power supplies. Power injection with one power supply it's very simple thing. And of course u shouldn't connect V+ together directly, but u can connect it through the led string.

I have some more drawings with 4 power supplies for better understanding what i mean.

 

There is no Thru. +12 and Gnd  are all just connections (traces from in to out. Only Data is the Thru (the chip)

You are relying in the parasitic resistance of the wire and Led trace to dissipate the unbalance currents. Your supplies will NOT share evenly.

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Conventional wisdom with multiple power supplies is to separate the B+ between the power supplies.  However as a general rule of thumb, you can get away with multiple power supplies when there are lots of pixels between the power injection points.

Using the drawing that Valentin posted a few hours ago, this would likely work fine, but I will point out that unless those are very small power supplies, that is massive overkill.  You don't need a separate power supply for each 50 pixels.  If those are 5 volt pixels, you should be able to use two injection points and if 12 volts, just one.  And in either case, using the same power supply.  The common 350 watt power supplies used by many of us could easily your 340 pixels with plenty of capacity to spare.

3 hours ago, Valentin said:

To prevent cutting of string connectors i use triple-side connectors (3pin male - 2pin female - 3pin female). It makes power injection simpler.

Pinj.png

 

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On 2/9/2019 at 02:28, Valentin said:

No, non sono in parallelo, perché ci sono stringhe di led tra di loro.

Nel tuo caso (340 lampadine):

0,3 W. * 340 = 102 W. Usando una regola dell'80%, dovresti avere un alimentatore 102 / 0,8 = 127,5 W (non conto la potenza del controller, perché sarà sufficiente per alimentarlo). Non dovresti realizzare in parallelo i cavi (+) degli alimentatori (solo i cavi GND).

Quindi, in caso di led a 12V, devi inserire una potenza ogni 100 led, ma nel tuo caso è meglio iniziare dal 51 ° led, quindi 151, quindi 251, quindi 340.

Ho provato a mostrarlo sulla foto.

Penso che sia meglio iniziare dal 51 ° per evitare il sovraccarico dello slot di alimentazione del controller. In quella situazione il controller alimenterà solo circa i primi 20-30 led, ma il carico di alimentazione principale della stringa sarà sugli alimentatori aggiuntivi.

Per evitare il taglio dei connettori delle stringhe, uso connettori a triplo lato (3 pin maschio - 2 pin femmina - 3 pin femmina). Rende più semplice l'iniezione di potenza.

Pinj.png

thanks for the advice, I meant in parallel on the pixel line, obviously

 

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On 2/9/2019 at 06:11, k6ccc said:

La saggezza convenzionale con più alimentatori è quella di separare il B + tra gli alimentatori. Tuttavia, come regola generale, è possibile cavarsela con più alimentatori quando ci sono molti pixel tra i punti di iniezione di potenza.

Usando il disegno che Valentin ha pubblicato poche ore fa, questo probabilmente funzionerebbe bene, ma sottolineerò che, a meno che non si tratti di alimentatori molto piccoli, questo è eccessivo. Non è necessario un alimentatore separato per ogni 50 pixel. Se questi sono pixel da 5 volt, dovresti essere in grado di utilizzare due punti di iniezione e, se 12 volt, solo uno. E in entrambi i casi, utilizzando lo stesso alimentatore. I comuni alimentatori da 350 watt usati da molti di noi potrebbero facilmente i tuoi 340 pixel con molta capacità di riserva.

 

Sorry if I ask you another question. I did as recommended by you, I only carry the data cable on the strings, I remove the positive to have no returns and feed the string with another power supply. In doing so, however, the bulbs flicker and make random color games, can you tell me what I can do? Initially I thought it was the data cable about a meter long between the bulbs and others of the same string, because I surrounded the Christmas greetings writing, I then thought about the small cable, but nothing changes. what can I do? thanks in the meantime

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18 minutes ago, Pioerpaolo said:

Sorry if I ask you another question. I did as recommended by you, I only carry the data cable on the strings, I remove the positive to have no returns and feed the string with another power supply. In doing so, however, the bulbs flicker and make random color games, can you tell me what I can do? Initially I thought it was the data cable about a meter long between the bulbs and others of the same string, because I surrounded the Christmas greetings writing, I then thought about the small cable, but nothing changes. what can I do? thanks in the meantime

Is your scheme like the scheme in the picture?

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The V- of the two power supplies needs to be tied to each other.

 

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I did it through the cables coming from the previous bulbs, do I have a cable from power supply to power supply?

 

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Just now, Valentin said:

Il tuo schema è come lo schema nella foto ?

The only change, as advised by Jim, is the negative shared with others

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yes, GND should be shared.
What's voltage of the strings? 5V or 12V? If 5V, they should be powered each 50 pixels. If string of 100 pixels: power it from start and frome the end of string.

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4 minutes ago, Pioerpaolo said:

I did it through the cables coming from the previous bulbs, do I have a cable from power supply to power supply?

 

I would recommend a good solid V- connection between the different power supplies.  Remember that V- is not only power return, but also the return for the data.

 

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Just now, k6ccc said:

Consiglierei una buona connessione V solida tra i diversi alimentatori. Ricorda che V- non è solo il ritorno di potenza, ma anche il ritorno per i dati.

 

Tomorrow I try with better tightening, I did a little flying with automatic mammoths to do tests and not having to do and undo trying, you say they could be those? Since this year is the first time I use the non-LOR pixcon16, I wanted to use 340 pixels to exploit fewer channels for the outline of the house, do you think it is right to do it or rather halve the strips and use more channels.

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U should check it step by step (every step should show estimated result):

1) check first 50 pixels;

2) connect second 50 pixels;

3) power the second 50 pixels from the 1st power supply;

4) connect 3rd 50 pixels and power it from the 2nd power supply.

5) and so on...

every step u should check any changes. In case of improper lighting, check every component.

Such way helps to find out the reason.

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grazxie valentino, that's exactly what I did. Tomorrow I will try to share the two V- of the power supplies, I will do better tightening and not flying ....... I will keep you informed, meanwhile, thanks

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On 9/8/2019 at 4:27 PM, Valentin said:

yes, GND should be shared.
What's voltage of the strings? 5V or 12V? If 5V, they should be powered each 50 pixels. If string of 100 pixels: power it from start and frome the end of string.

So let’s say I’m using your 2.1 example for my 12V pixels. Multiple strings with data connected along the way. Rather than run a 16 foot wire between each V- on the power supply, could I also connect the V- between  each strip and “T in” the V- from each power supply?

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1 hour ago, DocBrown86 said:

So let’s say I’m using your 2.1 example for my 12V pixels. Multiple strings with data connected along the way. Rather than run a 16 foot wire between each V- on the power supply, could I also connect the V- between  each strip and “T in” the V- from each power supply?

I think I see what you are doing. You are using many small (low amp) PS  located at the inject point.

I think most that do Power inject run from a big centralized PSU with numerous fused outputs.

The purpose of tying the negatives together is to reduce noise on the power in relation to the Data input (node 1)

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1 minute ago, TheDucks said:

I think I see what you are doing. You are using many small (low amp) PS  located at the inject point.

I think most that do Power inject run from a big centralized PSU with numerous fused outputs.

The purpose of tying the negatives together is to reduce noise on the power in relation to the Data input (node 1)

Yes. I’m putting small waterproof supplies I got off of Amazon at each stripe starting point.

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1 minute ago, DocBrown86 said:

Yes. I’m putting small waterproof supplies I got off of Amazon at each stripe starting point.

Good luck, you might want to stock up on some ferrite cores (loop both + and - thru the doughnut a couple of turns (similar to what LOR   does with the USB cable). That should kill some of the hash that escapes smaller units

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