Comparison Between Bus Duct and Cable
1. Price comparison of busway and cable cable:
Based on the price of the three-phase four-wire system 1000A per meter of line segment, based on the current market copper price of 40,000 per ton, the price of our company's busway is 1550 yuan per meter. The cable price is calculated at a price of 140 yuan per meter, the cost of the cable is 1120 yuan, plus the cost of the cable tray is 200 yuan per meter and 150 yuan for labor, and the actual price of the cable line per meter is 1470 yuan. Busway and cable cost similarly. But the performance of the busway far exceeds that of the cable.
2. Comparison of busway and cable installation:
The so-called plug-in busway uses plug-in method to connect the branch line to any line section on the busway trunk and install the plug-in box, so the split is very convenient. If the power supply needs to be cut off on any floor, the busway does not need to be powered off, and the normal power supply of other floors will not be affected. Generally, cables cannot be split at will; The disadvantage of prefabricated branches cannot be changed at will, and the branch connection method adopts the "C" type hoop of the opening, which can ensure the tightening force over time. In addition, the price of each branch head is expensive, so the application of prefabricated branch cables is still not widespread.
3. Comparison of busway and cable line overload:
The busway has a strong overload capacity depending on the conductor section sufficient to match the required current capacity. The busway aluminum housing is a non-conductive metal, so it has less inductance and less power consumption. The conductor ABCN interphase insulation material is made of polyester-based film with a voltage resistance of 5000V and a temperature resistance of 150°C in the United States to achieve high temperature and high pressure resistance. The normal working temperature of the insulation material used in the cable is generally 95°C and 105°C. On August 27, 2000, in disaster-ridden Russia, the world's second largest and European tallest building in Moscow's Ostankino TV Tower caught fire. The reason for this is due to cable overload. Therefore, the overload capacity of the busway is much greater than that of the cable.
4. Comparison of safety performance of busway and cable:
The busway shell is extruded and formed by aluminum alloy, and the surface is treated with electrophoretic oxidation to achieve fire and anti-corrosion performance. The current level of the busway ranges from 400A-6300A, and the cross-sectional area of the shell is several times larger than the phase area, and the grounding effect is more ideal, safer and more reliable. The insulation layer and skin of the cable are flammable insulation, and the flame retardant cable will also burn under flame. Fire-resistant cables are expensive, and only fire protection and other power sources that are not allowed to cut off fire-resistant cables are used. When a large current is required, only multiple cables can be used. Too many interfaces are easy to heat up, and long-term operation will cause the connector to turn black and scorch. Cause fire hazards. The three converters of Baosteel stopped production, that is, the high current used multiple cables to cause the connector to heat up, resulting in a fire.
5. Unique heat dissipation performance of busway:
The busway uses air conduction to dissipate heat, and the side panels are designed and combined in the form of heat sinks, and maintain uniform heat dissipation through a close-contact aluminum alloy shell. It can work for a long time in environmental places below 130°C. It can better dissipate heat. Therefore, its heat dissipation performance far exceeds that of cables. The insulation material of the cable (core insulation and skin insulation) is both an insulating material and a thermal insulation material, so when the power cable is laid in the tray, it is allowed to lay 2 layers, and the reason is to consider the heat dissipation of the cable.
6. Simple maintenance method of busway:
Once the busway is put into operation, it does not need to be repaired. Only routine maintenance is required, usually measuring the temperature rise of the housing and core bolts, the temperature rise of the joints of the inlet box, etc., and the connection of the core bolts can be checked and fastened regularly.
