Operating principle

In a measuring coil a material sample is exposed to a defined magnetic field and magnetic flux is created in the sheet steel. The required electric current is supplied by a power amplifier. The current is measured by means of a temperature-stable precision resistor being free of induction (shunt) or via field coils.

Determination of the polarization by measurement of the induced voltage, and then conversion and integration by means of a 16-bit processor. Parallel recording of the H and J sizes with separate recording systems guarantees absolutely simultaneous measurement. Faults in measurement caused by phase displacement are thereby ruled out.

From the differentiated and integrated parameters the processor system can calculate all the above mentioned values. There are no sources of faults such as analogue multipliers and integrators. Measurement is by means of sinusoidal polarization. By using a control algorithm the secondary voltage can be checked and controlled sinusoidally. The nominal voltage is supplied by a highly stable, quartz-controlled digital sinus generator. Amplitude and frequency are set by the processor unit according to the sample data entered (weight, density, desired frequency, nominal, polarization etc.).

Measuring coil systems

• Epstein frame for frequencies of 50 Hz / 60 Hz according to IEC 60404-2
• Epstein frame for frequencies of 400 Hz according to IEC 60404-2
• C 510 measuring coil for punched parts, cuts and strip
• Single strip measuring coil for Epstein strips, following IEC 60404-3
• Single sheet measuring coil according to IEC 60404-3 (500 x 500 mm)
• Module for rings, transformer cores and stators
• Custom-made Epstein frames, single sheet and single strip measuring coils

Operation, Measurement and Evaluation

MPG Expert software for easy operation of the instruments enables completely free parametering and structuring of the measuring processes. MPG Expert can be run under Windows.