Laminated insulated soft busbars, also known as flexible busbars, are made of multi-layer anti-corona flat thin copper conductors superimposed, and the outer layer is made of extrusion to cover the insulation layer.
1. Structural composition
The conductor of the flexible busbar adopts T2 soft copper strip, which can be divided into bare copper and tinned copper. Copper strip specifications are 6×0.5, 9×0.8, 15.5×0.8, 20×1, 24×1, 32×1, 40×1, 50×1, 63×1, 80×1,100×1, the number of lamination layers is generally 2 to 12 pieces directly, and the current carrying capacity is between 125A-1600A.
2. Insulating layer
The insulation layer of flexible busbar is currently available in two materials: specialty polyvinyl chloride (PVC) and thermoplastic elastomer (TPE). TPE has the characteristics of low smoke and halogen-free.
Second, production standards
Flexible busbar has not had a special standard in the world before, the United States borrowed UL758 electronic wire standard for production certification, China’s earliest reference to GB/T5023 insulated cable standard and UL758 electronic wire standard began to manufacture.
Third, the product characteristics of flexible busbars:
1. Easy to process and form
Since copper conductors can slide freely within the insulating layer, flexible busbars require unlimited bending and torsional characteristics. The copper bandwidth thickness ratio is different, so that the soft busbar can be easily bent in the thickness direction, but the width direction has high rigidity, so that the flexible busbar can bend out any space configuration with bare hands or using simple tools, which is convenient for installation and wiring.
2. High ampacity
Due to the skin effect, when passing through alternating current, the current inside the conductor is actually very small, the current is concentrated in a thin layer near the surface of the wire, and the multilayer flat conductor structure of the insulated soft bus bar makes the same conductor cross-sectional area can carry a larger passing current. This reduces the amount of conductor material, which saves both weight and layout space.
The following is a comparison of the cross-sections required for flexible busbars and ordinary cables under three types of ampacity:
Flexible busbar VS normal cable
3. Easy installation
After the flexible busbar is bent and perforated, the spatial shape of the structure can avoid the interference area, and it can easily return to the original shape after bending during installation, and the contact surface and the terminal post can be directly fixed slightly, eliminating the complex connection fixation of traditional cables and busbars.
Comparison of installation layouts
Fourth, the application of flexible busbars
Due to the excellent characteristics of flexible busbars, it has become the first choice for electrical wiring, and will gradually replace the application of cables in electrical wiring, and the hard busbars with non-main structure will also be gradually replaced by soft busbars.