| 摘要 |
PROBLEM TO BE SOLVED: To prevent a window frame from being fixed in the wrong direction. SOLUTION: An accommodating board main body of this watthour meter accommodating board is constituted of a base 1 and a cover 20. A window frame 30 is detachably fixed to a window hole 21 in the front surface of the cover 20. Inclination angles of a pair of slant surfaces 32a, 32b facing each other and interposing an exposure hole 31 are made nearly equal to the inclination angles of slant surfaces 25a, 25b of the cover 20, whose inclination angles in the vicinity of the window hole 21 periphery are mutually different. As a result, when the window frame 30 is fixed opposite in the vertical direction, the inclination angles of the slant surfaces 25a, 25b of the window frame 21 do not coincide with the inclination angles of the slant surfaces 32a, 32b of the window frame 30, and it can be easily judged that the window frame 30 is fixed in the wrong direction. Thereby the window frame 30 can be prevented from being fixed in the wrong direction (vertically reverse direction). |
