General Information; Measuring Magnetic Susceptibility; The Sensors - Bartington MS2 Operation Manual

The circuitry within the MS2 meter powers the sensors and processes the measurement
information produced by them. The measurements are obtained digitally using a time dependent
method. This results in precise and repeatable measurements. The sensors are independently
calibrated and are therefore fully interchangeable between MS2 meters.

4. General Information

4.1. Measuring Magnetic Susceptibility

Magnetic susceptibility corresponds to the ability of a material to be magnetised in an external
field. Bulk (volume) susceptibility χ
material: χ = μ - 1 and where μ
vol r
The MS2/3 instruments rely on the change of inductance in an inductor when the permeability of
its core is changed.
The reference state is measured when the sensor contains only air (the permeability of air is
approximated as the permeability of a vacuum). Taking a reading with a sample will then give the
permeability of the material.
Any thermally induced sensor drift needs to be eliminated by occasionally obtaining a new 'air'
value, to re-establish the zero reference. This is done by pressing the 'Z' button on the MS2
meter (see Front Panel
The magnetic susceptibility value is displayed digitally and output via a serial interface.
For further information on calculating the magnetic susceptibility and how it is related to
magnetic permeability, see

4.2. The Sensors

Each sensor subjects the sample to a non-saturating field that has the advantage of measuring
initial susceptibility without destroying any sample magnetic remanence. When measuring non-
metallic samples, the sensors are particularly insensitive to sample conductivity.
BARTINGTON INSTRUMENTS
can be directly related to the relative permeability (μ
vol
is the ratio of permeability of material/permeability of vacuum.
r
Controls).
Appendix 5. Calculating Magnetic Susceptibility.
Page 9 of 82
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r
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