What Is a Flexible Terminal?
A flexible terminal is a terminal for electrical supply that can be bent freely. They are a type of component used to supply electricity.
Flexible terminals can absorb thermal expansion, rapid contraction, and vibration. Unlike cables, they do not have an organic coating and can handle high currents. Due to their high flexibility, they are widely used in power generation and transformation, driving parts, etc. On the other hand, the charging section can be peeled off. Also, since the live part is exposed, it is necessary to take measures to prevent unauthorized persons from easily approaching it.
Uses of Flexible Terminals
Flexible terminals are used in a variety of industries.
For example, they are used in cranes and train pantographs to connect the electron collector to the cable terminal, ensuring both pantograph expansion and contraction, as well as a stable power supply.
They are also used for the connection of thyristors for electrolysis and for the pulling in of power receiving and transforming equipment, taking advantage of their ability to carry large currents. When bus bars are used as high-current conduits, flexible terminals are installed in the midsection to absorb elongation.
Principle of Flexible Terminals
Flexible terminals are divided into a terminal section and a flat braided section.
The terminal part consists of a bus bar with a hole in it. Bus bars are usually made of copper. The connection to the cable or other bus bars is made by fastening a bolt or screw through the hole. However, if the fastening surface is uneven, contact resistance will be high. In such cases, the fastening part will generate heat when a large current is applied, causing burnout or power loss. Therefore, the fastening surfaces are plated with solder, tin, silver, etc. to reduce contact resistance. This plating also serves to prevent corrosion.
The flat braided part is an important part that gives flexible terminals flexibility. The structure consists of several hundred strands of wires thinner than 1 mm2 in diameter, bundled and braided together. The strands are braided together in the same way as in clothing or carpets, making it both strong and flexible, and there is no need to worry about the strands breaking.
As with cables, the allowable current increases in proportion to the thickness of the conductor. The higher the allowable current, the heavier and larger both parts become.