| 摘要 |
PURPOSE:To enable the measurement of the quantity of electric power under various kinds of rating and specification, by using a frequency divider which frequency- divides a pulse frequency signal proportional to the quantity of electric power and whose freqency division ratio can be changed and by setting the frequency division ratio from the outside. CONSTITUTION:A frequency divider 11, which frequency-divides a pulse frequency signal proporational to the quantity of electric power, is so built that the frequency division ratio of the divider can be changed by frequency division ratio setting input terminals 12-15. When the terminals 12-15 are set shown in Tab., for example, ten frequency division ratios can be obtained. As a result, various frequency division ratios can be set when a pulse frequency signal which is obtained from a power converter 4 by multiplying a load voltage VL and a load current IL by each other and integrating a signal proportional to the quantity of electric power is frequency- divided. Therefore, a wattmeter with many kinds of rating and specification can be provided by setting frequency division ratios from the outside. Thus, the productivity of the wattmeter can be heightened. |
