The difference between dense insulated busway and air insulated busway

The difference between dense insulated busway and air insulated busway

The standard of dense insulated busway is defined as: "After covering the bare busbar with insulating material, place it close to the channel housing". The standard of the air-insulated busway is defined as: "The busbar is supported in the housing with an insulating gasket and insulated by air medium." The main difference between the two is the structure and insulation. When choosing the type of busway, comprehensive consideration should be given to their technicality and economy. From the perspective of selection and application, the performance and characteristics of two different forms of busway are analyzed.

The analysis of densely insulated busbars from a processing point of view, the manufacturing process is more complex; in terms of safety performance, insulation requirements are relatively high. Its advantages are: large current carrying capacity, good energy saving effect, good dynamic thermal stability, small size, good heat dissipation, low temperature rise, and is very suitable for large current transmission.

The air-insulated bus bar is analyzed from a processing perspective, and the manufacturing process is relatively simple; in terms of safety performance, the insulation requirements are lower than the dense insulated bus bar, and its insulation method is more flexible (wrapped or not wrapped), and it is convenient to tap. The disadvantages are: poor current carrying capacity, temperature increase, large impedance value, poor heat dissipation, and is not suitable for transmission of large current.

Current-carrying capacity (current-carrying capacity) is an important indicator for evaluating busbar products. A large number of test data has proved that the current-carrying capacity of densely insulated busbar troughs is superior to that of air-insulated busbars: current-carrying capacity of conductors of the same specification It differs by one current level or even more. 

The main reason for the poor current-carrying capacity of the air-insulated busbar is the large impedance value, large loss, and poor heat dissipation, resulting in a small allowable current. This is especially prominent in air-insulated bus ducts with large currents. For example, "A busbar slot uses densely insulated busbar slots, the current density can be selected around 1. SjAm; air-insulated busbar slots can only be selected around 1.2A/mmZ. In this way, under the same current conditions, the latter's cross-section (conductor) is much larger, resulting in increased costs and wasted resources.