50Hz 60Hz AC Electromagnetic Flowmeter 4-20mA 316L Stainless Steel / Hastelloy Material

An AC Electromagnetic Flowmeter Refers To An Electromagnetic Flowmeter

An AC electromagnetic flowmeter refers to an electromagnetic flowmeter that excites the excitation coil with industrial frequency (50Hz or 60Hz) sinusoidal alternating current.

Core technologies

• Mechanical zero adjustment method: An early approach, which involves manually adjusting the position of the transformer core in the signal loop to generate a reverse compensation voltage. This method is cumbersome and has limited effectiveness.
• Hardware quadrature suppression circuit (mainstream solution): A portion of the excitation current is diverted through a 90° phase-shifting circuit to produce a compensation voltage that is equal in magnitude and opposite in phase to the quadrature interference. This compensation voltage is then injected into the signal loop to cancel out the interference.

Comparison with Modern Mainstream Excitation Techniques

The AC electromagnetic flowmeter is a great transitional technology that solved the problem from 0 to 1, but due to inherent defects, it failed to achieve optimization from 1 to 100. It marked the turning point of the electromagnetic flowmeter technology from the exploration period to the mature period. Its historical lessons directly pointed out the development direction of modern electromagnetic flowmeters - low frequency, digitalization and intelligence.