| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a structure for extending the branch circuits of a distribution board that does not cause the phase interruption by the neutral conductor to impress an overvoltage to a load, even when branch switches for a 100V load and a 200V load are incorporated together. <P>SOLUTION: Three conductive bars that are each electrically connected to three terminals at either the primary or secondary side of a main switch connected to a single-phase three-wire wiring line via branch wirings are positioned at different heights to each other. At one side of a unit 51 of an extension branch switch, the negative side common terminal T1, which the conductive bar that is connected to one voltage line (L1 phase) is inserted into and connected to, is positioned at the height corresponding to the L1 phase conductive bar, whereas a selective terminal T2, which either one of the conductive bars of the other voltage line (L2 phase) and the neutral line (N phase) is inserted into and connected to, is positioned in such a way as to move freely between the height corresponding to the conductive bar of the L2 phase and the height corresponding to the conductive bar of the N phase. <P>COPYRIGHT: (C)2004,JPO |
