Third level distribution box: refers to the final junction box of each electrical appliance, which can be movable and fixed. Electrical equipment is installed under the switch box, forming a three-level distribution. In addition to installing leakage protectors in the final switch box, a first level leakage protector should also be installed. (3) Power distribution from tertiary switch boxes to electrical equipment must follow the “one machine, one switch” principle, with no branching allowed. Each switch box shall connect to and control only one associated piece of electrical equipment (including sockets). According to the hierarchical. Switchboard construction must ensure that all bare conductors and live parts are securely fixed to maintain required clearances and creepage distances. Built to meet specific safety and. It's better to replace the 2.