| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a power source changer which changes power sources safely and easily, without a burden to an operator and without performing unnecessary load reduction. SOLUTION: This power source change for a power receiving circuit is composed by connecting a plurality of power sources to a plurality of corresponding groups of loads through feeders, respectively, and inserting power source change- over switches in the feeder and electric circuits which connect the power sources mutually. A changeover signal is outputted to the power source change-over switch by measuring the quantity of electricity of a group of loads to be connected to a power source objective for cutting off and the quantity of electricity of a group of loads to be connected to a power source out of the objectiv for cutting off respectively, and judging that the power sources are capable of being changed over, when the sum of the quantities of electricity measured by a plurality of quantity-of-electricity measuring apparatuses is not larger than a quantity of electricity suppliable by power sources out of the objective for cutting off, when a power source change-over command is issued.</p> |
