EMI-shielded sleeve

protectionbraidedfor pipes

Environments where many electrical/electronic devices are working at the same time may create problems due to irradiation of electrical noise or due to electromagnetic interference (EMI). The electrical noise can seriously influence the correct function of all equipment. Electrical noise is a form of electromagnetic energy leaked by electrical devices such as vacuum cleaners, generators, transformers, relay controls, power lines etc. It can travel through power lines and signal cables, or fly through space as electromagnetic waves causing failures and functional degradation. In order to secure the correct function of an electrical equipment, precautions shall be taken against unwanted noise. The basic methods are (1) shielding, (2) reflection, (3) absorption, (4) bypassing. Merely from the conductor’s perspective, the shield layer that normally surrounds the power carrying conductors, acts as reflector for the EMI radiation and at the same time, as a way to conduct the noise to the ground. Therefore, since the amount of energy that reaches the inner conductor is attenuated by the shielding layer, the influence can be enormously reduced, if not fully eliminated. The attenuation factor depends on the effectiveness of the shielding. Indeed, different degrees of shielding can be chosen in relation to the level of noise present in the environment, the diameter, the flexibility and other relevant factors. There are two ways to create a good shielding layer in conductors.