| 摘要 |
<p>In this power-measuring device (1), a set-phase-relationship storage unit stores whether a load connected to a three-phase four-wire power supply is inductive, capacitive, or neither; that is, whether each phase current (Ia to Ic) lags, leads, or is in phase with that phase voltage (Va to Vc). The power-measuring device determines whether or not said stored phase relationship matches an obtained phase relationship. This makes it possible to detect a misconnection that could not heretofore be tested for; specifically, the case in which the primary conductor of each current transformer (4a to 4c) is connected backwards, with voltage terminals (3a to 3d) connected correctly.</p> |
