Benefit to doubling up PSU connection?

[Cornelius]

I've got a 12V PSU running to a 6 way fuse box, then that to my DC barrel connectors and out to the LEDS with various injection points.

Right now I have one cable running from the V+ and one from the V- running to the fuse block. Is there any added benefit (or bad idea) to running a second cable from the V+ and V- into the fuse block?

See images attached. And Thanks!

(12V 360W, running 15M of WS2811 (It's what I had laying around)).

 

[i13]

The extra screw terminals on the power supply are there so that you can connect multiple fuse boxes. That said, doubling the cables to the same fuse box would make sense. Every cable has some amount of resistance and therefore voltage drop along its length. Doubling the cables halves the resistance and therefore the voltage drop too. It also doubles the current that can flow before the cables can no longer handle it. Note that it is important that none of the cables break if you're running this much current because the remaining cable will be overloaded.

It is generally a good idea to make the cables between the power supply and fuse box as short and thick as possible. Thicker cables have lower resistance and voltage drop happens over distance.

 

[Cornelius]

The extra screw terminals on the power supply are there so that you can connect multiple fuse boxes. That said, doubling the cables to the same fuse box would make sense. Every cable has some amount of resistance and therefore voltage drop along its length. Doubling the cables halves the resistance and therefore the voltage drop too. It also doubles the current that can flow before the cables can no longer handle it. Note that it is important that none of the cables break if you're running this much current because the remaining cable will be overloaded.

It is generally a good idea to make the cables between the power supply and fuse box as short and thick as possible. Thicker cables have lower resistance and voltage drop happens over distance.

Thanks, That's what I was hoping. I cut some extension cords for this cabling, it should be 16 gauge braided at a minimum, most likely 14. I've got good crimpers and connectors to double these up. Thanks for the advice!

 

[TerryK]

A few thoughts. First your country avatar indicates the USA. Most extension cords in the US are 16 AWG and it is not uncommon to find 18 AWG in the cheaper ones. 14 AWG and heavier are available of course but one needs to read the 'fine print' and they are of course more expensive. The connections in the graphic look rather light weight to me, 16 possibly, I'm would be a little skeptical if they are 14 AWG although judging wire AWG from a photo is a 'shot-in-the-dark'. Be that as it may, as others have suggested, keep them reasonably short.

Amperage capacity of the supply and fused distribution block will determine wire size and the running of a single or multiple connections between them.

12 Volt and 360 Watt loosely calculates to 30 Amp. That means that for a single pair (+ and -) of conductors between the supply and distribution block, you should use 10 AWG. 12 AWG will work although I suggest only short lengths. There's some variance in the NEC ampacity charts (number of conductors in a raceway, ambient temperature, and all that stuff).
If the supply can shove 30 Amp, what is the rating of the fused distribution block? It needs to be at least 30 Amp too. If not, then fuses need added between them to limit the current to the fuse block.
One also needs to consider the amperage rating of the terminals. Aside from a best guess on terminal ratings as manufacturers seldom indicate terminal ratings, 30 Amp terminals are fairly common and having those on a 30 Amp supply would indicate a single conductor (10 AWG) would suffice. For lighter amperage terminals (again with a 30 Amp supply), the terminals would need strapped at the supply ideally or multiple conductors which may bring supply to distribution block fusing into the mix.

 

[algerdes]

Simply, combining two 12 awg wires creates a 9 AWG connection. https://www.wirebarn.com/Combined-Wire-Gauge-Calculator_ep_42.html