Magnets are essential componets in motors, position sensors, and many other devices and systems. Rare-earth magnets and electromagnets must produce the proper magnetic fields and magnetic flux for their intended applications. If your company uses magnets in production, then your QC department typically must measure magnetic fields in the air and magnetic flux in a surface when a magnet arrives at incoming inspection. Gaussmeters and fluxmeters can make those measurements.
Two articles on EDN by Jeffery Dierker, senior consulting engineer at Lake Shore Cryotronics, give you basic information about how gaussmeters and fluxmeters work, what features to look for, magnetic probe types, and how to use the probes. Ensure magnetic components meet specs explains the basics of magnetic fields, including units of measurement such as flux, flux density, magnetic-field strength, and permeability. You know the unit names: Oersted, Maxwell, Gauss, Tesla, and Weber.
Use gaussmeters and fluxmeters for manufacturing quality covers specifications, features, and applications, including how to use Hall-effect probes to maximize measurement quality. Dierker notes:
The user must ensure that the magnetic field is perpendicular to the probe sensor active area in order to achieve the most accurate reading. An even better option is to maximize the field reading by slightly rotating a transverse probe during test.
Fluxmeters can be mated with Helmholtz coils to measure magnetix flux. The figure below, Figure 7 in "Use gaussmeters and fluxmeters for manufacturing quality," shows how to use a slide fixture to move a magnet through a Helmholtz coil. The figure assures us that the magnet passes though the same way each time, providing for repeatable measurements.
A slide fixture can control magnet orientation
and motion path for better repeatability.