| 摘要 |
A switch status sensor (1) is provided for counting on/off events of a switch (3) of a water meter (5). When an on/off event is detected by microcontroller (11), the microcontroller (11) supplies a "signature" signal, which is distinguishable from electromagnetic noise to the switch (3). If this "signature" signal is detected as having passed through the switch (3) by the microcontroller (11), then it can be confirmed that the switch (3) is closed. Alternatively, if the "signature" signal is not detected as having passed through the switch (3) by the microcontroller (11), then it is verified that the switch (3) is open. Thus, the switch status sensor (1) can distinguish between false switch events caused by electromagnetic noise and true on/off events of the switch. |
