| 摘要 |
An arrangement for generating DC magnetic fields of alternating polarity for the magnetic-inductive flow measurement by means of a field coil which is connected via alternately controlled switching members to a DC voltage source, wherein during the reversal time following the change-over of the switching members a capacitor is connected to the field coil to form a resonant circuit separate from the DC voltage source and the capacitance C of the capacitor in dependence upon the desired reversal time DELTA t has substantially the value <IMAGE> wherein L is the inductance and R the ohmic resistance of the field coil. |
