| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an improved structure of a switchboard that makes it possible to suppress abnormal heat generation by an eddy current of a board frame with simple modification just adding simple parts to an existing board frame. <P>SOLUTION: In a switchboard in which bus bars 3 of a large current are laid at the side of the board frame 2 near the frame of a steel material provided vertically inside the board, magnetic shield members 4 made of electromagnetic steel plate having high magnetic permeability and high resistance are added along the board frame 2 in regions facing the bus bars 3. Specifically, the magnetic shield members 4, which form a laminate of silicon steel plates subjected to insulation treatment on the surface, are installed along the board frame 2. <P>COPYRIGHT: (C)2009,JPO&INPIT |
