Innovative concepts in magnetic shielding

In collaboration with VTT Automation, Euroshield Inc - one of the leading European manufactures of electrically and magnetically shielded enclosures - has developed a new cost-effective magnetic shielding concept. For a typical enclosure size of 3 m x 4 m x 2.5 m the shielding factor exceeds 60 dB at low frequencies and rises above 90 dB at frequencies beyond 10 Hz. This concept, which is based on two passive aluminium+mumetal shielding structures. For the passive shield, a new modular assembly technique has been developed and the pneumatically operated door gives and almost seamless wall surface in the closed position. In the active stage the demagnetizing coils installed in the passive shielding are used a noise filed sensors. In this way no external sensor are needed, a large number of signal are available for optimization of the shielding performance and a natural integration of spatially in homogeneous noise fields, corresponding to the shape of the shield, can be utilized.