| 摘要 |
For measuring the current cost of an appliance, current cost-measuring apparatus includes a line voltage unit, which plugs into an electric outlet and into which the appliance is plugged, and a remote light-weight portable cost-measuring unit. It is adapted to measure varying current utilization in a lower range or in a range eight times as great. A current transducer within the line voltage unit delivers both signals of both levels to the remote unit, which includes a high speed voltage-to-pulse converter, which has a somewhat limited straight line range of operation, and a low speed calculator unit. Their inconsistency is resolved by feeding the pulse output to a multi-stage binary divider at whose eleventh and fourteenth output stages are output taps. Since the division at the fourteenth stage is eight times that at the eleventh stage, selecting the higher divisor output compensates for selecting the higher level of signal of current used. Such selection permits advantageous use of the straight line range of the voltage-to-frequency converter. The frequency divider issues output pulses for chain addition by a computer chip of a cost figure per kilowatt hour. Using the fourteenth divisor stage, one output pulse is issued for about sixteen thousand input pulses; the input pulses themselves are not accumulated. Hence the computer chip with an associated display of the type used in inexpensive pocket calculators is sufficient to reflect cost of current utilized over a substantial period of time.
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