Let's take this shitty led apart and let's design a better one!

Eraserhead

Well-Known Member
Those Cidly panels have two 15 LED arrays connected to one power supply, there's a chance the drivers are failing, or the LEDs do not have built in protectors which keeps the current complete even if the LED burns out. Some LEDs have protectors, some do not.
 

patrikantonius

Active Member
So how would one array failing cause the other to burn out?
From what I understood, each driver provides two arrays with electricity, and the two arrays are wired in parallel
If the drivers are 1.4 A, in normal running conditions each panel receives approx 700 mA, but if one of the panels fails the other would then get the full 1.4A from the driver which would be dramatic.
 

Gastanker

Well-Known Member
From what I understood, each driver provides two arrays with electricity, and the two arrays are wired in parallel
If the drivers are 1.4 A, in normal running conditions each panel receives approx 700 mA, but if one of the panels fails the other would then get the full 1.4A from the driver which would be dramatic.
Ah, that makes more sense. I thought I read that the drivers were wired together in series as well as the arrays, not a single driver to two arrays in parallel.
 

Rasser

Active Member
The modules definitely should have all been burnt, there were still two of them remain, you have been lucky enough.
Each Apollo driver runs two modules and all drivers are connected as a series, this is why the Cidly claims- if one driver gets burnt, the other drivers will continue running the whole lamp in a good condition.
Yes, of course, this design could have been a great one if the LEDs had not been burnt too often. But unfortunately, the fact is at the opposite-their LEDs get more problems than their drivers.
What is the disadvantage of connecting all drivers together in a series? It means the total input current will never change however many LEDs or modules have been burnt.
Let me explain it more clearly- if one orb gets burnt, the total input current is still the same as before because all drivers are connected as a series, it means the rest running LEDs have to tolerate far more input current than ever before, and in fact, they have been driven at 700mA. And after one module gets burnt, the remain LEDs could be run at 800mA, 900mA.... and the more orbs get burnt, the more input current the rest LEDs have to tolerate... finally all of them get burnt if you don't turn off the lamp quickly.
For instance, the Apollo 4, if one orb gets burnt, each orb of the other three ones will have to tolerate more 1/3 input current, each LED will be run at 700mA+700mA x 1/3=700+233.33...= 933.33...mA, let's imagine what will happen....

Thank you very much.

I noted the link when I removed the fan grills, but did not think much about it, I thought maybe it's the new
protection system, but it looks like it's the new disaster system.

I have just remove the link from the unit.

 
I don't know much about LEDs/electricity so this might seem really stupid and be totally ass backwards but...

I thought these constant current drivers varied in voltage out but not mA out (or they wouldn't be constant current). So if you had say two 350mA 25-100v supplies in series they would put out 700mA between 50-200v based on what the LEDs are pulling. So if you had two 700mA arrays that each ran at 75v and you lost one then the second array would still be receiving 700mA but it would pull 75v total instead of the previous 125v.

Is this not true? I thought the whole reason behind using constant current drivers instead of constant voltage was to ensure mA delivery didn't fluctuate. Does the voltage not drop when the array burns out?

Like if I used this Mean Well driver: Mean Well LPC-35-700 constant current driver
Which operates at 700mA 9-48v; I could have it running 4 3wLEDs or 12 3w LEDs and all that would differ is the voltage, not the mA.
Yes, there is no doubt that the driver is definitely a constant current one, but it outputs total 1.41A, not 700mA. And there is another point at the electrics connection tech.
1. parallel connection- the input current will be double but the input voltage will not change (say:two orbs, each one built with 10x3W red LEDs 2.6V, 5x3W blue LEDs 3.8V, 15 LEDs connect as a series, 5x3.8+10x2.6=19+26=45V, the input current is 700mA, connecting these two orbs as a parallel connection, the input current will be 700x2, so they at least need a 45V,1.4A driver.);
2. series connection- the input current will not change but input voltage will be double or multiple(say:one 50W UFO 40x1W red LED 2.2V, 10x1W blue LED 3.2V all run at 350mA, run them in a series connection, 40x2.2+10x3.2=88+32=120V DC, but the input current is still 350mA).
There might be a good point to the cidly- it seems they are really going to avoid the high DC output and control it under 45V. We know, 100V DC could be more dangerous than 220V AC if there is an electric shock occurs.
 
Thank you very much.

I noted the link when I removed the fan grills, but did not think much about it, I thought maybe it's the new
protection system, but it looks like it's the new disaster system.

I have just remove the link from the unit.

Those white substances are just for convenient connection just like a computer electronics connection, but protector IMO.
 
From what I understood, each driver provides two arrays with electricity, and the two arrays are wired in parallel
If the drivers are 1.4 A, in normal running conditions each panel receives approx 700 mA, but if one of the panels fails the other would then get the full 1.4A from the driver which would be dramatic.
You are right, and they combine all drivers together, if one orb failed, those 700mA will spread to the rest orbs.
 

foreverflyhi

Well-Known Member
I posted this in another thread, I highly recommend seeing the video and maybe playing with the construction kit to get a hand on the basics when you get the time.

A guy on youtube is explaining it's functions Here and giving a crash course in ohm law.

Click image for site.




Edit: Someone really stoned said in a post above "
The modules start lighting up at about 27 volts so it's difficult to test them without a laboratory power supply."

Now the question is, why not just use 3 9V batteries in series Dohh, there is plenty of light in the LED's at 27V
to see if they are working and are all shining the same.

One could always add a 1.5V battery to the chain and 28.5V is so far from 36V where the module draws 700mA(the maximum "allowed") so it's safe.
It should also be easy to connect the 3 batteries together, but I think you have to cut the plug off the wire to the module to test it on the 27V battery, you can always use cable joints if it turns out that the module is fine.



should i make this a test??
 

foreverflyhi

Well-Known Member
The modules definitely should have all been burnt, there were still two of them remain, you have been lucky enough.
Each Apollo driver runs two modules and all drivers are connected as a series, this is why the Cidly claims- if one driver gets burnt, the other drivers will continue running the whole lamp in a good condition.
Yes, of course, this design could have been a great one if the LEDs had not been burnt too often. But unfortunately, the fact is at the opposite-their LEDs get more problems than their drivers.
What is the disadvantage of connecting all drivers together in a series? It means the total input current will never change however many LEDs or modules have been burnt.
Let me explain it more clearly- if one orb gets burnt, the total input current is still the same as before because all drivers are connected as a series, it means the rest running LEDs have to tolerate far more input current than ever before, and in fact, they have been driven at 700mA. And after one module gets burnt, the remain LEDs could be run at 800mA, 900mA.... and the more orbs get burnt, the more input current the rest LEDs have to tolerate... finally all of them get burnt if you don't turn off the lamp quickly.
For instance, the Apollo 4, if one orb gets burnt, each orb of the other three ones will have to tolerate more 1/3 input current, each LED will be run at 700mA+700mA x 1/3=700+233.33...= 933.33...mA, let's imagine what will happen....
you are right and i have results from the test to prove this.
 

foreverflyhi

Well-Known Member
So how would one array failing cause the other to burn out?
simple, cheap design.
the question should not be why, but how we can improve this for our future led unit?
ill write that down on our list of improvements

Those Cidly panels have two 15 LED arrays connected to one power supply, there's a chance the drivers are failing, or the LEDs do not have built in protectors which keeps the current complete even if the LED burns out. Some LEDs have protectors, some do not.
how can we improve on that?
 

foreverflyhi

Well-Known Member
so pretty much this test should clarify what Rasser, davemedinis, patrikantonius, Along with others had previously said.

i first plugged in the unit as it previously was,
row "A" had module2 full blast and module3 dimmed
row "B" had module 3 full blast
the rest of the modules do not work.

i then unpluuged everything (keep in mind i will be conducting test the with same wiring as it origninally was)
photo (16).jpgphoto (10).jpg


i first wanted to start with row A and the working module2 and driver2.
driver2+module1=nothing
driver2+module2=full blast
photo (14).jpg
driver2+module3=dimm, this tells us that module3 is broken and driver2 is working.
photo (13).jpgphoto (11).jpg
driver2+module4+nothing
photo (18).jpg
this is when the test goes sour,

driver1+module1=nothing
driver1+module2= full blast, then within 10 seconds it starts to blink multiple times, then its dimms
photo (13).jpg
driver1+module3=dimm, same as before, once agian this could be a indication that driver works, but then agian this driver and module2 completly just failed!
driver1+module4=nothing

so i dont feel the need of posting the rest of the results of row A results are the same as the others.(unless u absoultly need them)

ok so now row B
i decided just to start with driver1
driver1+module1=nothing
driver1+module2=nothing
driver1+module3=fullblast, but within seconds the same occures, it blinks then it dimmed, however it didnt dimm as much as module2 from row A, it still has some power, but by no means full blast
photo (15).jpg
driver1+module4=nothing

the rest of the results are the same, i dont feel the need to post, unless otherwise.

ok so now what does this test tell us? it can mean alot of things
i think these leds and modules are busted, just like it was stated earlier, each one would eventually go out.
so whats next?
how should we further test these modules and or drivers?
how can we redisign this led unit?'
how can we upgrade it?
 

Rasser

Active Member
"driver1+module2= full blast, then within 10 seconds it starts to blink multiple times, then its dimms"

That was what I saw when trying to run the driver with only one module connected.
(I think the driver has current sensing on it two outputs, so if it's measure 700mA on one channel and not the other it's shuts down.
I'm not sure, but the behavior of the driver points in that direction.)


Thinking about what a dummy load could look like: 36.8V / 0.7A = 51ohm's
A halogen flood light on 250 or 300W should make the driver think a module is connected,'
and will then not start to blink and shutdown so a real module can be tested on the other channel,
or as a driver test with two dummy loads connected.
250W / 120V = 2.0A = 120V / 2A = 57ohm
300W / 120V = 2,5A = 120V / 2A = 48ohm.

And 1000 watts if the light bulb is a 230V model.

Edit: I Read your results as this - we have gone from whats is broken to "Okay what do we got on this spacecraft that's good"
Module 1 & 2 are at full blast(or that's how it appears) - the 4 drivers are properly working ok, connecting the two working modules
or a dummy load to each one of them should show that.


15 LED module pcb see though btw:
 

Rasser

Active Member
Hi.

What about constructing a test circuit to test the individual RED LED's on those modules that are dark.

A 9V volt battery and a 15 Ohm 5W resistor some wires and you up and running, can find a resistor use a 12V 10W halogen light bulb.



 

Rasser

Active Member
Just saw this great short multimeter tutorial, that covers what it should.

[video=youtube;bF3OyQ3HwfU]http://www.youtube.com/watch?v=bF3OyQ3HwfU&feature=g-vrec[/video]

What the status on the situation with the broken panel ;-)
 
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