What is a terminal block? | Significance and Types Marathon BUSSMANN Power Distribution Block, 620 A Max. Amps, Number Of Poles: 3 - 4XK20|16500-3 Power Distribution Block Catalog Power Distribution Blocks are devices designed for centralized electrical distribution. They typically include input terminals, output terminals, and common busbars, making wiring more organized and safer Power distribution blocks (PDBs) and terminal blocks serve distinct purposes in electrical systems, despite their similar appearances. PDBs are specifically designed to split power from a single input to multiple outputs, handling higher current capacities and voltage levels