Is a closed busway a busway or not?

Yes, busbar is one of a kind.

Tray: A tray is a bracket that supports and puts cables. It is the abbreviation of cable tray.

Cable tray: The cable tray is divided into trough type, tray type and ladder frame type, grid type and other structures, which are composed of brackets, brackets and installation accessories.

Busway: A closed metal device composed of copper and aluminum busbars, which is used to distribute large power to the various components of the dispersion system. It has nothing to do with cable trays.

Unlike busways, it can transmit and distribute current. The tray only serves as a protective function for the outside of the cable.

The role of the busway: instead of the tray and cable tray: the tray.

If you need these things, there should be a lot of manufacturers who come to you to use their products and give you some samples, and you know that they are two completely different things and should not be mixed up.

The closed busbar is a bus system composed of metal plates (steel plates or aluminum plates) to protect the shell, conductive bars, insulating materials and related accessories.

In the process of operation, the closed bus is often affected by many factors such as the shaking of the unit, the change of the temperature difference between the inside and outside of the bus, and the aging of the sealant, which leads to the destruction of the original sealing structure of the closed bus, and the free circulation and replacement of the air inside and outside the bus, and the dust, impurities, charged particles, and water mist in the outside air will invade the inside of the bus, causing pollution to the inside of the busbar.

Separation of phase closure uses:

Separation closed bus is a kind of high-current transmission device widely used in the outgoing wire circuit of generators of 50MW and above and the branch circuit of the factory.

If you look at the name, you will know that it is a bus bar that encloses the main bus with a metal shell. Closed busbars have the following advantages:

1.It is conducive to standardization and has good interchangeability.

2.The enclosure is generally made of non-magnetic or weak-magnetic materials to reduce heat generation.

3.The bus bar is closed, and the anti-pollution ability of the system is improved, which is suitable for coal, papermaking, chemical industry and other areas with serious dust and high air humidity.

The closed busbar is composed of a current-carrying conductor, a shell and an insulating material, and the busbar housing should be made of high-quality cold-rolled steel plate with sufficient mechanical strength and a protection level of IP55. The current-carrying conductor should be made of electrical copper material in accordance with GB5585 1 5585 3 standard, and the contact surface of the conductor contact has been specially treated to make the connection part contact reliable, low heat, safe and reliable use. The insulating material should have good insulation performance, anti-aging, non-toxic, low smoke and other performance indicators.

There are two kinds of closed busbars, one kind of closed bus has a large current carrying capacity, but it is not resistant to high temperature, can only work at a temperature of 200 °C, and is generally installed on the line that transmits mains, and this kind of bus is also called dense closed bus; Another kind of closed bus can withstand high temperature, generally under the condition of 700 1000 ambient temperature, can maintain 1 5 hours of transmission operation, its current carrying capacity can reach 5000a, this kind of closed bus is called fire-resistant closed bus. The difference between the refractory closed bus and the dense closed bus is the shell part, the shell of the refractory closed bus is coated with a layer of refractory coating, while the surface of the dense closed bus is sprayed, smooth, and the anti-corrosion layer has strong adhesion. Therefore, when the bus is used in the design of fire protection line and emergency power supply line, fire-resistant closed bus bar is used.

The fire-resistant closed bus requires a relatively large space during installation, and it is inconvenient to bend, but there are fewer accessories during installation. At the same time, the fire-resistant closed busbar can prevent the damage of small animals, and it is convenient for future operation and maintenance after installation. For example, the current carrying capacity of 450 630A bus** is 1000 yuan, plus other installation costs, about 1100 yuan.

When the fire-resistant closed bus is installed, it is necessary to pay attention to the insulation resistance value of the closed bus by using the shake meter and make test records and keep records, and the insulation resistance should be greater than or equal to 20m. Because the fire-resistant closed busbar is 25m in sections.

During construction, the resistance value should be measured every time a closed bus is installed. When the copper busbar is connected, it is necessary to pay attention to the coating of conductive paste, and the bolt connection should be tightened to prevent fine seams between the copper busbars of the closed busbar. However, if the bolt is tightened too tightly (the author's experience is more than 34 N), the insulating porcelain block at the connection of the fire-resistant closed bus bar will be crushed, resulting in a decrease in insulation.

If the bolt connection is loose, when the torque of the bolt is less than 27 N, there will be a fine slit at the bus connection, resulting in poor contact and increased resistance of the busbar. When the torque is between 29 and 33 N, there is no fine slit at the connection of the busbar, and the insulating porcelain block between the busbar is intact. If the insulation resistance is less than 20m, it is that the bolt connection is too tight in one or several places, and the insulation resistance between the bus bars is broken and the insulation resistance is reduced, so the problem can only be found by the segmented method.

When the length of the closed bus is more than 80m, the bus expansion joint should also be installed, which is the bus trunk unit with axial change, which is installed in the appropriate position to absorb the axial change due to thermal expansion and cold contraction.

The difference between the bus bridge and busbar used when connecting the low-voltage side of the transformer and the low-voltage cabinet and the closed side-Xun busway:

1. How to use: the bus bridge is the most primitive and needs to be processed on site; After the busbar is supported by an insulator, the low-voltage cabinet is laid directly by the transformer; After the length of the bus bar is determined by the closed bus duct design, it can be installed directly on site after being made in the manufacturing plant.

2. Structural complexity: the bus bridge needs to cooperate with the bracket and use insulators to support the busbar; The bridge bracket of the steel structure is arranged between the transformer and the low-voltage cabinet of the busbar, and the insulator is also arranged on the bridge; The outside of the closed busway busbar is closed with a metal box, and the inside is supported by an insulator, leaving enough safe space between the busbar and the shell, 3. **: The busbar is the cheapest; The busbar bridge is second; Closed busway is the most expensive.

With the emergence of modern engineering facilities and equipment, the electricity consumption of all walks of life has increased rapidly, especially the emergence of many high-rise buildings and large-scale workshops, the traditional cable as a transmission wire has been unable to meet the requirements of the high-current transmission system, and the parallel use of multiple cables has brought a lot of inconvenience to the on-site installation and construction connection. As a new type of distribution wire, the bus tray came into being, compared with the traditional cable, it fully reflects its superiority in the high current transmission, and at the same time, due to the use of new technology and new technology, the contact resistance and temperature rise at the junction of the two ends of the bus duct and the junction of the distribution port are greatly reduced, and high-quality insulating materials are used in the bus tray, so as to improve the safety and reliability of the bus tray and make the whole system more perfect.

In fact, it is a copper bar, or other composite materials instead of cables