| 摘要 |
PROBLEM TO BE SOLVED: To realize reduction of the size of a switch by simple means.SOLUTION: A watthour meter includes a terminal part 13 having power supply side terminals 1S to 3S connected to a commercial power supply, and load side terminals 1L to 3L connected to a load. The watthour meter has an internal circuit where a first switch 16 for connecting/disconnecting the power supply terminal 1L and 3L to/from the load side terminal 1L and 3L is connected to two pairs of the power supply terminals 1S and 3S and the load side terminals 1L and 3L, out of the three pairs of the power supply side terminals 1S to 3S and the load side terminals 1L to 3L. The remaining pair of the power supply side terminal 2S and the load side terminal 2L are short-circuited in the terminal part 13. A second switch 17 for connect/disconnecting the remaining pair of the power supply terminal 2S and the load side terminal 2L of the terminal part 13 is disposed as a switch separated from the first switch 16.SELECTED DRAWING: Figure 1 |
