Passive Magnetic Shielding
Depending on the application, requirements and environment, passive magnetic shielding can be the most suitable solution to use, in order to reduce low-frequency magnetic fields.
Electrical equipment, transformers, medium-voltage equipment, cable trays and NMR are example of sources that can be shielded, whether it’s for protecting EMI sensitive tools like electron microscopes or lithography writers, or achieving local regulation for human exposure.
Sometimes a combination between active magnetic field cancellation and passive shielding are necessary, particularly for high end transmission electron microscope and noise free rooms (requirements <10 nT).
Lab Protect is able to provide 3D magnetic field modeling of electrical power stations, NMR stray field and perform measurements on site to offer guarantees to reach specifications.
Depending on the application, different shielding alloys are selected for efficient passive shielding. Typically, a combination of nickel-iron / silicon-iron and aluminum is used to shield AC magnetic fields. Heat treated mu-metal is applied where DC-fields needs to be reduced. When required, custom-made design is also possible.