Soken tester - is a portable single yoke instrument for assessing the
power loss
A power outage (also called a powercut, a power out, a power failure, a power blackout, a power loss, or a blackout) is the loss of the electrical power network supply to an end user.
There are many causes of power failures in an electricit ...
in
electrical steel laminations.
It has been developed for quick assessment of power loss in electrical steel sheet without the need for cutting and annealing, as it is the case for standardised methods like
Epstein frame
An Epstein frame or Epstein square is a standardised measurement device for measuring the magnetic properties of soft magnetic materials, especially used for testing of electrical steels.
The International Standard for the measurement configur ...
.
The power loss can be estimated at 1.0
T, 1.5 T and 1.7 T and two frequencies 50 Hz and 60 Hz. Lamination thickness can be set within a range from 0.01 mm to 0.99 mm and there is no option for selecting the material
density.
The power loss is measured as a product of
magnetic field
A magnetic field is a vector field that describes the magnetic influence on moving electric charges, electric currents, and magnetic materials. A moving charge in a magnetic field experiences a force perpendicular to its own velocity and to ...
and
flux density
Flux describes any effect that appears to pass or travel (whether it actually moves or not) through a surface or substance. Flux is a concept in applied mathematics and vector calculus which has many applications to physics. For transport ph ...
. Both these signals are detected from the magnetising yoke, which is contained in an aluminium head (55 mm in diameter as shown in the photo). The flux density is measured from a secondary winding wound on the yoke. For that reason there is a great influence on the measured values, hence great care should be taken that the measuring head is placed on a clean and even sample. The measurement is based on similar principle as employed in the standardised
single sheet tester.
The manufacturers of the instrument claim that its
measurement uncertainty
In metrology, measurement uncertainty is the expression of the statistical dispersion of the values attributed to a measured quantity. All measurements are subject to uncertainty and a measurement result is complete only when it is accompanied by ...
is lower than 5% (as referred to results from Epstein frame).
The Soken tester has been developed in the second half of 20th century initially as a relatively cheap and easy to use analogue device, but recently also digital devices are available.
References
{{DEFAULTSORT:Soken Tester
Magnetism