Choosing a power supply for led

sprite

Member
I have been reading up on things about diy led. I built a fixture with 3 blueacro half stars that are 24w each. It lists the channels as 12v fit reach channel on a single star. I used 3 stars and my power supply is 48v 96w. I'm not really giving all the volts the LEDs can handle am I?


Sent from my iPhone using Tapatalk
 
Oh boy..
First.. Do NOT connect power to them until we figure out what you are using....
Please post a link to the exact LED modules you are using..


From what I see on their website their clusters are just LEDs only and as such need to be powered by a constant current power supply not a constant voltage power supply..

A 48W 96W power supply is how one would typically specify a constant voltage power supply which cannot be used by itself without an upstream constant current module like a meanwell LDD,etc.. or their own blueacro drivers..
Like these..
https://blueacro.com/acroiq

Do you have those too?
 
Oh boy..
First.. Do NOT connect power to them until we figure out what you are using....
Please post a link to the exact LED modules you are using..


From what I see on their website their clusters are just LEDs only and as such need to be powered by a constant current power supply not a constant voltage power supply..

A 48W 96W power supply is how one would typically specify a constant voltage power supply which cannot be used by itself without an upstream constant current module like a meanwell LDD,etc.. or their own blueacro drivers..
Like these..
https://blueacro.com/acroiq

Do you have those too?



Yeah I have their driver... Sorry I left that out


Sent from my iPhone using Tapatalk
 
X2, either that or ditch the 48 V powersupply and get two AC to DC constant current power supplies like this https://www.ledgroupbuy.com/inventronics-42w-driver-700ma/ (Just an example, I would go with a meanwell personally) Fewer parts may help and it is the simplst way to put together a build. How are you planning on controlling it?



I have the blue acro driver. I'll be controlling it with my reef angel set on 0-5 pwm


Sent from my iPhone using Tapatalk
 
They are working... Wired in series.It's that if my power supply is 48v and reach channel on 1 Star is 12v and I have 3 stars. Wouldn't my power supply need to be 72v? Or is the driver just delivering 12 volts to reach channel across all the stars?


Sent from my iPhone using Tapatalk
 
Here is my build

dea31489070781df88cf4fcc7d4b10a2.jpg



Sent from my iPhone using Tapatalk
 
Is there somewhere I can go to read how to choose a power supply for a build. I have a 4th star I'm thinking of adding to this string but I'm not positive my current power supply will be enough for it or I'll have to seperate them into 2 strings each.


Sent from my iPhone using Tapatalk
 
Is there somewhere I can go to read how to choose a power supply for a build. I have a 4th star I'm thinking of adding to this string but I'm not positive my current power supply will be enough for it or I'll have to seperate them into 2 strings each.


Sent from my iPhone using Tapatalk

you only really need to know 2 things to ballpark a power supply..
1)Diode V(f) at your desired current and how many in the string.
If unequal strings take the highest voltage one.
IF you want to do things REALLY "official".. Set your channel on 100% and measure the voltage across the plus/minus for that string while on.
CAUTIOUSLY of course
https://electronics.stackexchange.c...s-vf-in-order-to-pick-an-appropriate-resistor
BLYB4.png

Crude but explains how to gather the required info.
Think of the one diode pictured as your serial string of diodes..
Think of the power supply as your driver.
Don't need the resistor either..
Just check voltage parallel and amps series.
It's a lot easier than it sounds.
ONLY need to check amps to SET your driver if you are using a variable current one.
Don't really need to check things like Meanwells w/ built in set point.
IF you accidentally under volt your string yet have enough voltage to power the diodes somewhat then an amp check would confirm it. Because you don't have enough voltage at the diodes they won't draw enough current and will then test lower than the drivers setpoint.
Testing amps (as pictured) allows you to adj. your driver 's current.

Once you measure your current voltage of all 3 pucks then divide by 3 and that will get you the fairly exact voltage required for 1 puck..
Then take that x4... This assumes all pucks channels in a row are the same.
Otherwise just ballpark from the V(f) or test when all 4 are hooked up

That voltage will change by the amount of current your driver is set for..
More current, higher voltage.
The driver acts as a voltage regulator.. only changing it as needed to keep a steady state current..

2)As to amps.. easiest "ballpark' is just add number of channels w/ whatever current you are driving them at..

Say you have 2 channels, each at 1A ..2A capable power supply..
To get really fancy take the ACTUAL voltage you measured for each channel and multiply it by the drive current.
Will give you actual watt/channel.
Add them up and buy accordingly.

Say you measure the real voltage at 22.5V and driving them at 700mA
15.7W
Say the other channel measures 23.3v and you set it to 1A
23.3W

So use a 24V power supply capable of outputting 15.7 + 23.3W = 39W (1.625A)...
(CAUTION, some drivers "lose" a few volts from ps to string.. i.e you may have a 24V power supply but the driver is only capable of outputting 22V Amount of "loss" is driver dependent)
Add at least 10% to the watt capability for a fudge factor
42W or whatever..

Like I said earlier # of drivers and add the current . In the example 1.700

Just remember voltages add in series and current divides in parallel (not recommended to put them in parallel though, just add another driver,,

did this writeup late.. so hopefully any error s someone will correct
 
Last edited:
You tube is always a clear choice


Is there somewhere I can go to read how to choose a power supply for a build. I have a 4th star I'm thinking of adding to this string but I'm not positive my current power supply will be enough for it or I'll have to seperate them into 2 strings each.


Sent from my iPhone using Tapatalk
 
Back
Top