I'm fairly new to this and have been going back and forth on the proper power supply I should use.
I have 135 LEDs each on 6 data pins, using 20 AWG wire. Using an Arduino Mega with a 1000 uF capacitor and a 220 ohm resistor on each pin.
Each LED according to the manufacture takes 0.3W or 60mA to power each LEDs. Thus requiring 250W or 50 Amps based on calculation. The manufacturer recommends a 100W power supply for each reel (16.4 feet).
The LED light strip themselves account for roughly 7 feet per strip, 43 feet total. The total cabling on each strip comes to 9 feet, 54 feet total.
Right now I have a 75W power supply that struggles with whites and has a lot of flickering on some colors. But almost does the job. I will probably need something bigger as I figure injecting voltage at the end might solve the issue (lights don't actually need to be very bright, it's for background/ambient purpose), running more wiring will make the display a bit less cleaner and was hoping NOT to.
My question is, should I be putting 60 Amps through using 20 AWG wire? It doesn't sound entirely safe, especially when I don't need this to be at full brightness. Should I go for the 20, 25,30,40 amp power supply instead? Should I just inject voltage at the end and find a way to hide the cabling?
I'm not entirely sure what the course of action should be to minimize voltage drop, whether it be going with more current, bigger power supply or injecting voltage at the end would be best.
"My question is, should I be putting 60 Amps through using 20 AWG wire?"
No. 20 AWG is only rated for 11 Amp.
(The Maximum Amps for Chassis Wiring is also a conservative rating, but is meant for wiring in air, and not in a bundle. )
I currently have the power connected to the power rails on my breadboard and each strip is attached to it as well, obviously. So are you saying instead of going with one large supply, to remove them from the power rails and give them their each individual supply? Not sure if I have the space for 6 power supplies. Wouldn't I need 6 wall outlets? Seems a bit overkill, maybe there's just something I'm not understanding. Thanks for the advice.
All that power going thru a breadboard? You're lucky it hasn't got hot & melted.
I would connect the strips direct to the power supply. That might be enough to solve the flickering and similar problems. If not, then add a 2nd supply, power 3 strips from each one (75W = 15A?), or a 3rd and power 2 strips from each.
Got to plan for worst case software error and you accidentally send full bright to all LEDs, don't want stuff to smoke if that happens.
All Gnds must be connected, and the Arduino supplying the signals must attach to the same Gnd.
I did a card with 165+ large (2835) white LEDs in parallel for a photo booth (55 strings of 3 LEDs). Drew less than 4A, but the 12V 4A supply was humming pretty good. So bright we couldn't tell if all LEDs were on. I was holding the card under a desk after we assembled each on to power them up. Ended up PWMing the drive transistor at a really low duty cycle and looking with sunglasses to make sure all the LEDs worked.
Turned out to be way too bright, 2nd pass only had 27 LEDs per card
Don't overload any one supply or you may find yourself opening them up to replace a fuse.
