摘要 |
An optical-electronic demand meter using an optical metering outfit (MOF) is disclosed. The optical-electronic demand meter includes: a light emitting device driving circuit for sending light rays through an optical fiber to an exclusive optical MOF; a light receiving device driving circuit for receiving optical voltage and current signals as modulated optical signals from the optical MOF so as to convert them into electrical signals; a zero point adjusting circuit for adjusting the zero point of the converted electrical voltage and current signals; a multiplying circuit for multiplying the output voltage and current signals so as to form power signals; an active/reactive power separating circuit for separating the power signals into active power signals and reactive power signals; a power summing circuit; an effective value converting circuit for converting the absolute values of power into effective values; a voltage/frequency converting circuit for generating pulses of frequencies corresponding to the output of the effective value; an integrating and displaying circuit 90 for calculating and integrating the pulse signals, and for storing and displaying the integrated data; and a power source circuit. In the demand meter, there is not required a separate insulating device, and the demand meter is capable of carrying out reliable arithmetic operations and integrations for the proper amount. |