With cross-tie disconnector “DT”, the power of line A can be switched to branch A1, bypassing the busbar. The busbars are then accessible for maintenance. Each branch requires only one circuit-breaker, and yet each breaker can be isolated without interrupting the power . The starting point for planning a switchgear installation is its single line diagram. This indicates the extent of the installation, such as the number of busbars and branches, and also their associated apparatus. Designing a substation involves not only the visible equipment and ratings but also the less apparent factors—operational. Do you know how to correctly apply the NEC requirements for switchboards, switchgear, and panelboards? Article 408 covers the specific requirements for switchboards and panelboards that control power and lighting circuits. Currently, Thor is the Technical Department Manager at Weisho Electric Co.
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