What Is Shielded Cable

Shielded cable is a special cable that is shielded and insulated around the cable to reduce electromagnetic interference (EMI). The shielded cable can make the external electromagnetic radiation and magnetic field radiation directly enter the ground without interfering with the inner wire. In general, the shielded cable has two layers. The shielding layer, the mesh braided wire is to prevent magnetic field radiation, and the aluminum foil layer is mainly used to prevent electromagnetic radiation. The shielding layer must be grounded in order to have a good shielding effect. When the external electromagnetic field with higher frequency passes through the shielding layer, it will generate eddy current and be lost.

Shielded cable is a special cable with mesh braided wire on the outer layer of the cable. Cable shielding means that the mesh braided wire on the outer layer of the cable has been grounded at one end, so that the external electromagnetic radiation and magnetic field radiation can directly enter the ground without affecting the inner wire. produce some disturbance. Better shielded cables generally have two layers of shielding, the mesh braided wire is used to prevent magnetic field radiation, and the aluminum foil layer is used to prevent electromagnetic radiation. Generally, coaxial cables are used for cable television, leads from frequency converters to motors are used, shielding is required for power supplies where there is interference, and analog leads are also used.

Shielded cables require anti-interference to prevent external electromagnetic fields from entering the line. Generally, lines with high frequency and low signal level need to use shielded cables. The most common one is the cable TV coaxial cable. In addition to the inner conductor, there is usually a layer of metal mesh outside for shielding, which is also one of the signal loops. In addition to the core wire of the copper wire, the core wire of the communication cable is wrapped with a layer of aluminum foil and grounded to play a shielding role.