i am making a arduino project using 5v ws2812b 300leds/meter. Its going to be a motion activated led strip that runs along the side of the stairs. I will be using 3.5m of the led strip so 210leds at 60mA so if all white on full power they will consume 12.6 amps.
I have a 5v 40a meanwell power supply so plenty of overhead. I will put a 1000uf capacitor on the positive and ground leads of the wires just before they reach the leds and 480 ohm resistor on the data line.
I am concerned with voltage drop over 3.5 meters so i will run the wire along the led strip and inject power every meter. My question is what gauge wire should i be using?
The psu will be under the stairs so wire will be 5m long. I am worried about heat and would like some advice about any safety or fire concerns i should be thinking about.
Should there be a fuse in the circuit?
This is the best schematic i can find to show how its wired, where would the fuse go? Power is coming in from both ends of the led strip, would this suffice for a 3.5m strip
Best Answer
The recommended wire size for 13A is 19AWG (which is hard to find) so get 18AWG. 3.5m of 18AWG wire is about 0.12Ω, which would be about 1.5V of loss. So a larger size of cable or paralleling the wires (multiple strands of 18AWG) might be the best way to go.
If you're worried about something shorting and heating up, then yes, put a fuse in. A 20A fuse would ensure that you don't blow the fuse but protect against short circuits.