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19-Oct-2007
SC22 Magnetic Field Cancelling System
SYSTEM SC22
•
Protects your investment in electron
beam technology by stabilising the
magnetic field environment
•
Cancels and monitors the AC field
•
Low cost, high performance system
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Intelligent user interface
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Automated set up
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Cancels AC fields from 0.5 Hz to 5 kHz
50 x field improvement at 60Hz
•
Full 3 axis (X, Y, Z) system
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Up to 60 mG (6.0 µT) pk-pk range
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Adapts to field changes within 100 µs
•
Supports dual sensors for TEMs and
high gradient fields
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USB monitoring port
Overview
Today’s high performance electron beam tools
are very sensitive to changing ambient magnetic
fields. The fields move the beam causing loss of
resolution and measurement accuracy. The
SC22 system reduces the ambient AC field and
restores the resolution and accuracy.
The SC22 system comprises a Magnetic Field
Control Unit, an AC Magnetic Field Sensor and
three multicore cables, which are installed in the
room where the field is to be cancelled.
Each power amplifier in the control unit drives a
current through its cable to create a field of the
opposite sign to the change in ambient field.
The magnetic field sensor measures the
resulting field and real time negative feedback
reduces the ambient field by the loop gain of the
system.
The
system
is
dynamic,
automatically
responding to field changes within 100 µs. AC
Line fields (50/60 Hz) are reduced by 50 x.
The SC22 does not cancel DC field changes
from sources such as elevators, trains and
traffic. The larger SC20 system is available to
cancel both AC and DC fields.
SPICER CONSULTING
SPICER CONSULTING, Eden Laboratory, Broadmead Road, Stewartby, Bedfordshire, England MK43 9ND
Tel: +44 1234 765773 Fax: +44 1234 765778 E-mail: [email protected] Web: www.spicerconsulting.com
