Many customers often encounter the problem of coil selection when choosing a fluxmeter to measure magnetic materials. Because a fluxmeter can only measure the magnetic flux of a magnet with a coil. The coils may be monolithic coils, fixed B coils or Helmholtz coils.
1. As for the single coil, you can wind it on the sample yourself, or you can make a sleeve larger than the sample, put the sample inside and pull it out for testing.
2. A fixed B coil is used for testing, basically one test coil for each sample size.
3. Helmholtz coils can be used for testing. Helmholtz coils can be used to measure a range of sample sizes (this requires the customer to provide a minimum and maximum sample size).
Fluxmeters that measure with Helmholtz coils are usually more commonly used.
Because when using a fluxmeter (table), a permanent magnet is usually used to "put the method", and the magnetization of the sample is related to the magnetic flux of a set of planar coils. This method is intuitive and effective for each sample of different specifications, but has disadvantages It is necessary to use coils of different sizes and strictly use thin samples. The preparation of detection coils is difficult, troublesome and inefficient. However, measuring the magnetic flux with Helmholtz coils can solve the above problems to a certain extent, so measuring the magnetic flux with Helmholtz coils in one magnetic flux is the best method
