A shielded cable comprises a conductor that is enclosed by at least one cable shield (conductive sleeve). This shielding protects the inner conductor from electromagnetic influences. It also prevents electromagnetic radiation emanating from the signals carried by the conductor from escaping into the environment. Multiple cable shields can be used to improve shielding strength.
For variable speed operation of three-phase asynchronous motors (e. g. in conjunction with centrifugal pumps), it is recommended that the connection cable between the frequency inverter and motor terminal box be shielded.
A coaxial cable is an example of this type of cable.