If current branches off throughout the run, each portion gets considered with its wire size and corresponding current. Applicable portions that are in series accumulate the voltage drop percentages.

Example:

Load 1 and Load 2 are both 5A loads.

Circuit 1 is the main branch circuit to both Load 1 and Load 2.

Load 1 is connected immediately at the end of Circuit 1.

Circuit 2 continues from the position of Load 1, onto Load 2.

Voltage drop across circuit 1 is 1%, based on the gauge/length of Circuit 1 and a combined load of 10A.

Voltage drop across circuit 2 is 0.8%, based on the gauge/length of Circuit 2 and a load of 5A.

The voltage drop from the source to Load 1 is 1%.

The voltage drop from the source to Load 2 is 1.8%.