Busbar Channel Design Applications and Installation

Application of Enclosed Busway Trunking in High-Rise Buildings

In high-rise buildings, the architectural profession will allocate space (shafts) for the installation of enclosed busway systems. Each floor is equipped with one or more junction boxes, from which power is supplied to various electrical equipment and circuits via cables and wires.

When designing, pay attention to the following points: ① To ensure the continuity of power supply lines, consider using a double-circuit configuration and maintain a certain safety margin between the two circuits as much as possible; ② When selecting the specifications for a closed busway, increase the conductor cross-section to ensure adequate remaining capacity; ③ Increase the number of plug-in interfaces, but consider the operating height and power feeder routing, as an excessive number of plug-in ports on a vertical closed busway can make the height of the plug-in box on each floor too high, making operation and maintenance inconvenient; ④ Due to the low impedance of the closed busway, when selecting circuit breakers for the plug-in boxes, choose models with short-circuit breaking capacity that matches; ⑤ For closed busways vertically installed on shear walls, it is not necessary to provide load data to the architectural designer. The load data should be calculated using the following formula: Support point load = 0.5 × building height × (total weight of busway / total length of busway); ⑥ Since the closed busway structure is much heavier than cable trays, consider the hoisting space during design.

Closed Busway Slot Application Precautions

When selecting a design, it is necessary to verify (calculate) the dynamic stability and thermal stability of the selected model based on the system's short-circuit current value and the parameters on the sample.

2. According to the current electrical explosion-proof regulations of the safety department, enclosed busbars are not suitable for Class A or B fire and explosion-proof locations. The main reason is that the connection methods at various junctions of the enclosed busbar still do not meet the explosion-proof requirements.

3. Closed busway systems are more expensive, and their use in situations with concentrated loads or where separate power supply equipment is required is not always economically sound from a construction perspective. Moreover, the installation of closed busway systems requires advanced technical skills, naturally leading to higher installation costs. Therefore, before deciding on the use of closed busway systems, it is essential to conduct a technical and economic comparison with other alternatives.

4. Enclosed busway systems are generally maintenance-free, but in environments such as coastal areas or textile factories where they are exposed to moisture or corrosive gases, they should be coated with anti-corrosion paint and maintained every one to two years.