A secondary distribution box, also known as a sub-distribution panel, generally supplies power to a specific area. It is designed with inner and outer doors, features a sprayed plastic exterior for safety and appearance, and also has a rainproof top suitable for outdoor work. Let's make an example for clarity: A newly constructed residential area introduces a 10kV power line to a substation. From the transformer's low-voltage side (0. It is specially designed for the special situation of the project construction site and meets the relevant construction power specifications and standards of the. From there, power is further distributed to the secondary distribution boxes located in each building, and then to tertiary distribution boxes in each unit, ultimately reaching individual households. A feeder usually begins with a feeder breaker at the distribution substation. Many feeders leave substation in a concrete ducts and are routed to a nearby pole.