Kett LE-373, Руководство по эксплуатации

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• LH-373
( E d d y C u r r e n t m e a s u r e m e n t m e t h o d : F o r
measuring the thickness of insulating coatings on
non-magnetic metal substrates)
An eddy current is produced in the surface of a metal
when a coil through which a current of fixed frequency
is brought near the metal. This eddy current and the
voltage at the ends of the coil change in proportion to the
distance between the coil and the metal surface. This
change can be determined from the current value and
this is used to calculate the thickness of the coating.
• LE-373
(Electromagnetic measurement method : For
measuring the thickness of non-magnetic coatings
on magnetic metal substrates)
When an alternating current electromagnet is brought
near iron (or other magnetic metal) the number of
magnetic flux lines passing through the coil changes in
proportion to the distance, thereby causing a change
in the voltage at the ends of the coil. This change in
voltage is determined from the current value and this is
used to compute the thickness of the coating.
• LZ-373(Dual Electromagnetic and Eddy Current Type)
The model LZ-373 is a dual type coating thickness tester which features both the electromagnetic and Eddy Current
measurement methods.
Induction coil
Insulating Coating
Non-Magnetic Metal
Thickness D
High-Frequency
Power Supply
Current
Change i
Low-Frequency
Power Supply
Non-Magnetic Coating
Iron • Steel
Thickness D
Electromagnetic coil
Current
Change i
i