My PSU outputs 5A max, so we’re not talking crazy thick wires here. But generally speaking best I could do is use much thicker cable, maybe 2 in parallel for each? Is that right?
it depends on what voltage drop you're want to see.
For example 5 Amps, 2 meters (total length 4 meters) solid round pure copper wire:
- diameter 0.1 mm, R = 8.546 Ω, voltage drop = 5 * 8.546 = 42.73 V
- diameter 0.5 mm, R = 0.3418 Ω, voltage drop = 5 * 0.3418 = 1.71 V
- diameter 1 mm, R = 0.08546 Ω, voltage drop = 5 * 0.08546 = 0.43 V
- diameter 2 mm, R = 0.02137 Ω, voltage drop = 5 * 0.02137 = 0.11 V
- diameter 3 mm, R = 0.009496 Ω, voltage drop = 5 * 0.009496 = 0.05 V
- diameter 4 mm, R = 0.005341 Ω, voltage drop = 5 * 0.005341 = 0.03 V