The secondary spot network bus is concurrently fed by two or more primary feeders via network transformers. Spot Networks are used for customers with the highest reliability requirements. Customers demanding a much larger amount of power may be connected directly to the primary. However, many electrical beginners don't know how to install and connect the distribution box. (1) Wiring method of distribution box 1) Generally, the incoming line of. Core idea: Distribution lines are the local electric circuits that carry power from distribution substations to customer service areas. Engineering use: Engineers review feeders, laterals, transformers, protective devices, voltage drop, loading, switching, and reliability. The. The best distribution system is one that will, cost-effectively and safely, supply adequate electric service to both present and future probable loads—this section is intended to aid in selecting, designing and installing such a system.