| 摘要 |
An electrode power meter capable of monitoring the contact status of a built-in latch relay according to the invention comprises: a built-in latch relay which includes a secondary side contact point operable to be open and closed between a closed position for supplying power from a power source side to a load side and an opened position for blocking the supply of power from the power source side to the load side, and a pair of primary side coils providing magnetic force for opening and closing the secondary side contact point; a meter control unit which is connected to the built-in latch relay, compares the input voltage of the primary side coil of the built-in latch relay with the output voltage of the secondary contact point of the built-in latch relay, determines that the built-in latch relay is at the closed position when the input voltage of the primary side coil is substantially the same as the output voltage of the secondary side contact point within a predetermined tolerance, and determines that the built-in latch relay is at the opened position when there is the input voltage of the primary side coil but there is no output voltage of the secondary side contact point. |
