Tektronix TCP300A, Руководство пользователя

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Glossary
Hall device
A thin, rectangular piece of semiconductor material located in the core of the
current probe. The Hall device uses the Hall effect for DC and low-frequency
AC measurements.
Hall effect
The effect that produces a voltage potential in the Hall device when magnetic
lines of
fl ux pass through the device. The voltage potential is directly
proportional to the magnetic fi eld strength. The voltage polarity is determined
by the magnetic fi eld polarity. A bias supply is required to produce the Hall
effect. The TCP300 and TCP400 Series current probes use the Hall effect for
DC and low-frequency AC measurements.
insertion impedance
The equivalent series impedance introduced to a test circuit when the current
probe is clamped around a test conductor.
magnetic susceptibility
A fi gure expressing the amount of current induced into the probe by an
external magnetic fi eld of known intensity. The lower the fi gure is, the less
the probe is in fl uenced by external magnetic fi elds.
saturation
A condition that occurs when the magnetic fi eld strength in the probe core
exceeds the maximum level that the core can absorb. When saturation occurs
the probe no longer responds linearly to an increase in magnetic
fi eld strength,
resulting in measurement inaccuracies. A current overload condition will
cause core saturation. After saturation occurs, the probe core usually retains
residual magnetism, which continues to produce inaccuracies until the probe
is degaussed. The probe should be degaussed after saturation occurs.
62 TCPA300/400 Ampli fi ers and TCP300A/400 Series Current Probes User Manual