From a performance perspective, the main differences between bus ducts and cables are as follows:

1. The current carrying capacity of the bus duct is better than that of the cable

Better than cables within the current carrying range. At present, cables can only reach a cross-sectional area of 1000mm and a rated current of 1600A, but these large-sized cables are rarely used in practical applications and engineering due to their large volume and weight. Engineering power distribution generally uses cables of 400mm or less, requiring multiple cables to supply power simultaneously. The maximum rated current of the bus duct can reach 6300A, and its strong current carrying capacity is the foundation of the cable.

2. The heat dissipation performance of bus ducts is better than that of cables

The insulation material of the bus duct has good heat dissipation performance (core insulation and sheath insulation), which is both an insulation material and a thermal insulation material. Therefore, when laying power cables on cable trays, a maximum of two layers are allowed to be laid. The reason is to consider heat dissipation. The busbar trunking adopts air conduction for heat dissipation, and the heat is dissipated through tightly contacting steel shells. Therefore, its heat dissipation performance is comparable to that of cables, and the heat dissipation performance of cables is evident.

3. Bus duct is almost maintenance free

The daily maintenance of bus ducts usually involves measuring the temperature rise of the casing and core bolts, as well as the temperature rise of the incoming box joints. If the core bolt is grade 4.8, it needs to be tightened regularly. If grade 8 is used, it should be tightened regularly Grade 8 high-strength bolts do not require regular tightening. However, due to limitations such as material wear, aging, and short lifespan, it is necessary to regularly inspect, maintain, and even replace cables.

4. Bus duct can prevent overload and fire

On August 27, 2000, a high-rise building suddenly caught fire at the Ostankino TV Tower in Moscow, Russia. The reason is caused by cable overload; The shutdown of Baosteel's three converters was also caused by a cable fire. The insulation layer and outer skin of ordinary cables will burn, and flame-retardant cables will also burn under flames. They will only burn after the flames have left. Fire resistant cables do not burn, but they are expensive. Fire resistant cables can only be used for firefighting and other power sources that are not allowed to be cut off. The casing of the bus duct is made of metal and will not burn. Even if the insulation material of the copper busbar burns, the flame will not escape outside the bus duct.

5. Bus duct is more convenient for cables

The so-called plug-in bus duct refers to the use of a plug-in method to connect the power supply of the main line to the branch line. There is a plug-in box port every few meters, so it is tapped. Very convenient. The cable needs to be tapped on site, which has poor reliability. Even prefabricated branch cables have obvious drawbacks. They mainly need to be customized for factories. The branch connection method uses an open "C" - shaped clamp. Can we guarantee a long time? Tightening force? In addition to the high price of each branch head, prefabricated branch cables have not yet been widely used. Any floor needs to cut off the power supply, and the bus duct does not need to be powered off. Just remove the plug-in box of the bus duct when it is unloaded.

6. Bus duct has stronger overload capacity

The strong overload capacity of the busbar depends on the high operating temperature of the insulation material used. The insulation material used for bus ducts is over supported and uses materials with a working temperature of 105 ℃. The working temperature has been set. Radiation cross-linked flame-retardant winding tape (PER) and radiation cross-linked polycarbonate heat shrink tubing above 140 ° C. The normal working temperature of the insulation material used for cables is generally 95 ℃ and 105 ℃, so the overload capacity of the bus duct is much greater than that of the cable.