摘要 |
A magnetic flowmeter generates an alternating potential (V19) representing flow. A controlled current (I12) excites the flowmeter with first and second amplitudes of current. A correction output (I26) represents the first and second amplitudes. A circuit (36) connected to the correction output (I26) and the alternating potential (V19) oscillates at a frequency representing the alternating potential corrected for variation of the first and second amplitudes. Frequencies of the oscillations at first and second amplitudes are measured (38). An output is calculated (39) as a function of a subtraction of the first and second measured frequencies such that the effect of offset is reduced.
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