A distribution board (also known as panel board or breaker panel) is a component of an electricity supply system which divides an electrical power feed into subsidiary circuits, while providing a protective fuse or circuit breaker for each circuit. DCDB may refer to: Digital Cadastral DataBase · Direct Current Distribution Board · Dickenson County Discussion Board. DCDB: Array Junction Box, DC Distribution Box Array Junction Box (AJB) also known as DCDB (Direct Current Distribution Box), component of an electricity. what is direct current distribution box- connections of dcdb box- uses of dcdb box- dcdb box in. dcdb and power supply instalation totorial. What is AJB? AJB (array junction box) is also known as DCDB (direct current distribution box).