In the face of the strong current required by huge load, safe and reliable power transmission and transformation equipment must be selected, and bus duct will be the ideal choice. Next, let's talk about the principle of bus duct system and the relevant contents considered in selection and installation.
Bus duct system is generally used in the connection between transformer and distribution cabinet and the power supply system with tree dry wiring from the distribution center (distribution panel and cabinet) to the load. The current grade of the system is usually 250 ~ 6300A, the rated voltage is 400 ~ 1000V, and the protection grade is IP40 ~ IP68. According to the number of conductors, three-phase four wire system and three-phase five wire system are configured (independent PE bar is added, and some manufacturers provide aluminum alloy shell as the form of integral grounding PE).
The bus duct system is generally composed of the following units: feeder bus (without socket) or plug-in bus (with socket) linear section unit; Incoming (outgoing) line units that interface with transformers, distribution cabinets and other equipment; The reversing unit includes L-shaped unit, T-shaped unit and Z-shaped unit; Expansion unit has expansion joint and bus unit; The plug-in unit has a plug-in box unit. All units are usually designed by the bus duct manufacturer according to the standard, or non-standard design can be adopted after on-site measurement according to the needs of the project, so as to meet the needs of users and installation.
The selection of bus duct is generally considered from the following aspects: fire protection requirements, insulating materials should have good flame retardant and heat resistance, do not release toxic gas at high temperature, and prevent chimney effect in structure. Dense insulated bus duct should be preferred. If air insulation type is selected, fire blocking partition should be set for each unit in the trunking shell; For particularly important places, in order to ensure the maintenance of emergency power supply in case of fire, fire-resistant groove shall be selected.
As for the installation site, consider the protection grade of the trunking shell, followed by the influence of the building structure on the shape, installation support form and span of the trunking: in the indoor special workplace, such as the high-capacity substation, in order to improve its heat dissipation effect, the bus duct with IP30 grade can be used; For ordinary indoor work, such as floor electrical shaft and distribution room, in order to ensure safety, bus duct of no less than IP40 grade shall be selected; Indoor damp places or places with splash prevention requirements.
In order to ensure that it can still work normally in case of splashing, bus duct with grade no less than IP54 shall be selected; Resin insulated bus duct can be used outdoors or in places with special requirements, such as anti water spray, anti wave and anti-corrosion; In places with large span, shell reinforced bus duct shall be selected; The rated current should be comprehensively considered from the aspects of technical performance, heat dissipation effect and price. At present, aluminum alloy shell low impedance dense insulated bus duct with good heat dissipation performance and low energy consumption is widely used in the market.
The advantages of power transmission and transformation of bus duct can not be compared and surpassed by ordinary power cables, especially to meet the needs of economic and reasonable wiring of high-rise buildings and large-scale factories. When you choose bus duct, we will solve the increasingly complex control problems in the construction field with good solutions to ensure the safety and reliability of power transmission. For more information, you can visit www.sddlqj.com Cn consultation!