Wiring from the power supply to the LEDsUpdated a day ago

Choosing wire size

Remember that the power coming out the DC end of the PSU, although at a lower voltage, will now be at a considerably higher current: eg for a 300W 120V input, 24V output supply, the mains input current is 300/120 = 2.5A, but the output DC current is 300/24 = 12.5A. So this of course makes a huge difference to the choice of wire size – you cannot use the same type of wire to wire up both sides to the PSU. Ohm’s law will produce an ever-increasing loss of voltage in the wiring as the current and the length increases, and this in turn will show up as dimming of the LED brightness and warming of the wiring.

Avoid using long wires with large currents; it is better to locate the power supply closer to the center or to use additional power supplies. Long wires are prone to voltage drops (dimming) and fires (due to overheating).

Feeding long strips

Inside the LED strip there is not much space for heavy wire, with the result is that the thin copper will cause a noticeable voltage drop (and therefore dimming). The thinner the LED strip, the worse the voltage drop becomes. For longer lengths, the strips should be fed from both sides or broken into smaller sections and fed from separate supplies or transformers with multiple outputs, as shown in the example below.