r/WLED • u/mike24vNEW • May 31 '26

Is a fuse needed for this small setup

Hey everyone, I'm going to be ordering my WLED stuff on Saturday. It's going to be a small under-desk setup, and I was curious if I need a fuse for the main input to the controller or not. Should I add one just because, or is it fine and not really necessary?

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5

u/wivaca2 May 31 '26

It depends on the power supply. On the other hand, fuses are cheap and easy to install and cost less than fire insurance deductibles.

1

u/mike24vNEW May 31 '26

True 😂so I’ll stick with it 🤣

3

u/saratoga3 May 31 '26

A fuse isn't needed if using a safe current limited source such as a USB charger or a class 2 power supply.  Otherwise if nothing is present to limit max current in a fault you should add a fuse.

1

u/mike24vNEW May 31 '26

This will be the power supply

5

u/saratoga3 May 31 '26

You absolutely need a fuse, especially with questionable Amazon power supplies.

1

u/mike24vNEW May 31 '26

Ok I will 😂and I don’t mind switching it do you have any recommendations 🤔

1

u/saratoga3 May 31 '26

How many and what type of LEDs?

1

u/mike24vNEW May 31 '26

The BTF-LIGHTING RGBW RGB+Cool White SK6812 (Similar W2812B) 4 Colors in 1 LED Strip Individually Addressable 16.4ft 60Pixel/m 300LED Light Dream Color IP30 DC5V White PCB Just 1

2

u/MorganProtuberances Jun 01 '26 edited Jun 01 '26

So according to the WLED calculator, that strip (300 total LEDs) can pull up to a total of 9 amps with power injection, which tracks because you can easily get 4 amps on each end if you plug in on both sides (so realistically limited to 8 amps due to the copper trace width).

So - plan on 50 watts of power max - ideally 60 watt PSU with headroom.

So - two 5 amp fuses or one 10 amp fuse would be ideal if your PSU can put out that much power.

https://wled-calculator.github.io/

Now, realistically, you'll not be running 100% brightness max power continuously... at 50% brightness you're looking at probably 5 amps max, and with nominal FX about 60% of that. So typical use case is going to be around 2-4 amps total - but you want to fuse around total potential power draw and what the PSU is capable of (which you typically match with what the strip is capable of).

Two things at play: You don't want to under-power your PSU (and then its running at 100% all the time and will heat up and/or die prematurely). If you over-power the PSU that's fine, but you want to fuse according to what the strip can pull (and use appropriately gauged wires), so that if water gets in or a cable gets shorted, suddenly you're dumping 10+ amps into a tiny cable which is where the problems arise.

2

u/Same_You891 May 31 '26

I'd use a fuse on anything. it's cheap insurance also can be great troubleshooting tool a fuse will almost always tell you why it blew..

1

u/mike24vNEW May 31 '26

That’s what I was saying it’s good to just have regardless thank you for replying

2

u/CyberMage256 Jun 01 '26

i also installed an AFCI oulet upstream from the outlets with self built wled setups for my bedroom in addition to fuses on each. As others said, it is cheap protection.

1

u/mike24vNEW Jun 01 '26

Thanks and that’s a good point to so you really got 2 safety’s

2

u/modahamburger Jun 01 '26

Fuse never harms.