Accuracy Based On Positioning And Direction - MAGSYS IGM11 Operating Instructions Manual

Industrial Gaussmeter IGM11 Operating Instructions
Chapter 3 Function of the Gaussmeter
As B as well as B is measured in the unit Tesla, the magnetic field measured on the
r
outside is often mixed up with the remanence.
Please note that a magnet without back iron only shows a value clearly below the rema-
nence on the surface. Due to the local and geometry-dependent measurement, the
remanence of the workpiece cannot be checked reliably with a gaussmeter.

3.2.3 Accuracy Based on Positioning and Direction

Since the measuring value depends on the position, an accurate and repeatable meas-
urement depends on the exact positioning of the probe during the measurement.
The measurement on the pole center of the magnet is most uncritical. When moving the
probe on the pole surface of the magnet, the measuring value hardly changes at first.
When changing the distance though, the measuring value varies considerably.
The smaller the magnet to be measured, the stronger even slight misalignments change
the measuring value. For quality-related research it is essential to ensure the positioning
accuracy.
Since a Hall probe only records one field strength vector, the correct alignment relative
to the magnet is important.
Please be particularly careful when measuring at the zero point at pole transitions. By
slightly tilting the probe, you measure additional lateral field shares that seem to dis-
place the zero passage.
In normal applications, a maximum flux density value is usually determined at a given
position. The measuring probe is placed in position and varied in location and direction
until the maximum is found. The device supports this measurement with the peak hold
feature.
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