Power Distribution Backplanes
A distribution board (also known as panelboard, breaker panel, or electric panel) is a component of an electricity supply system that divides an electrical power feed into subsidiary circuits, while providing a protective fuse or circuit breaker for each circuit in a common enclosure.
These power supply backplanes carry 12V power from the power supplies to the power distribution board over a pair of bus bars. They also delivers 3.3V standby power over a three-pin wire cable.
Figure 1: An example of a Power Distribution Board