| 摘要 |
PROBLEM TO BE SOLVED: To provide a power measurement unit eliminating the need of setting work for voltage of a load connected to a branching breaker, and capable of accurately measuring power without a setting error.SOLUTION: Voltage detection means detects voltage from a conductive bar for supplying AC power supply of a single-phase three-wire system. Current detection means 38 detects current flowing from a branching breaker connected to the conductive bar to a load side. The current detection means 38 is installed so as to make a phase of current detected by a load of 100 V and a load of 200 V oppose to a phase of the voltage detected by the voltage detection means. A computing section previously holds information about a phase of current of a load R100 of 100 V and a phase of current of a load R200 of 200 V detected by the current detection means 38 to the phase of the voltage detected by the voltage detection means. The computing section determines the voltage of the loads from the phase of the voltage detected by the voltage detection means and the phase of the current detected by the current detection means 38, and computes power on the basis of the determined voltage of the loads. |
