HELMHOLTZ COIL INSTALLATION AND CALIBRATION
Once the orthogonality is completed, both the scaling and dc
offset should be checked again and adjusted if required.
7.
Running the coils
Once the calibration of the system has been checked and is running satisfactorily, the coils can
then be used. It is recommended that the system is left running for 6 hours prior to use. If the system is
to be used daily, it should be left on permanently (though not necessarily generating field). The system
can be checked at regular intervals using the supplied equipment. Any changes to the local environment
should lead to a check of the system for DC offsets.
If you are using the coils to calibrate a magnetometer assembled into a system which contains
ferromagnetic material, the field generated inside the coils will be distorted by the presence of
ferromagnetic material within it. Best accuracy will be achieved when the complete DUT us located within
the Coil’s homogeneous volume of
1%.
Figure 15: X and Y errors
due to Z adjustment
potentiometers