Project Data
 Slideshow
VitaTech Engineering was contracted to design, install
and test an AC extremely low frequency (ELF) dual-substrate magnetic
shield in a first floor laboratory in Marlborough, MA. Extremely low
frequency (ELF) magnetic fields emanated into a first floor laboratory
generating electromagnetic interference (EMI) in the color CRT computer
monitors (screen jitter), laboratory test equipment (digital noise)
and in-house development projects. The field source was from the main
electrical switchgear (480V/277V 1600 amp) and two electrical closets
adjacent to the laboratory.
A 1,600 square-foot dual-substrate magnetic
shield was installed over two days on the first floor EMI affected
laboratory wall and floor areas adjacent
to
the main electrical switchgear room and two electrical closets. The dual-substrate AC ELF magnetic shield installed in
the first floor laboratory complies with (actually exceeds) the final
performance objective of less than 5-mG (actually between 1-2 mG) over
95% in the shielded areas measured 1-meter from the shielded wall and
floor under all building load conditions.
Magnetic Shield Images
Building with Shielded Lab in Marlborough,
MA
Before Shield
A three-dimensional spatial representation of the mapped area over a superimposed
reference grid. The before shield 1-meter magnetic field levels peaked
at 281 mG.
After Shield
A three-dimensional spatial representation of the mapped area over a superimposed
reference grid. The after shield 1-meter magnetic field levels were between
0.6 - 1.72 mG.
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