METHOD OF CONTROLLING MAGNETO-INDUCTIVE FLOW RATE METRE Russian patent published in 2009 - IPC G01F1/60 G01F25/00 

FIELD: physics measurements.

SUBSTANCE: invention is intended for self-diagnostics of flow rate metre. The proposed flow rate metre comprises a fluid medium measuring tube and a magnetic field system incorporating, at least, one filed coil carrying, intermittently, excitation current I_m. In control, voltage U_H, exciting current I_m at the given moment, is varied from the second value U_drv to constant third value at time interval t₂ to decrease I_m from its maximum to preset finite I_cont. Note here that the third voltage value is selected to be smaller than U_drv. To define the third time interval t₃ that corresponds to reaching I_cont, I_m is periodically recorded. This allows defining the first time constant t_short for the magnetic field system that corresponds to time interval t₃ - t₂, and/or the second time constant t_rev + t_short, for the magnetic field system, that corresponds to time interval t₃ - t₁. To define the flow metre diagnostics state representing its operating state at the given moment, t_short is compared with the preset first reference value, and/or t_rev + t_short is compared with the preset second reference value.

EFFECT: higher accuracy in defining flow metre fault during current measurement cycle, simplified procedure.

4 cl, 12 dwg