| 摘要 |
An ampere-hour meter has a current generator 4 connected across a resistance 3 through which the load current passes, generator 4 charging a capacitor 11 with a charging current which is proportional to the current in the load circuit, but is independent of the voltage across the capacitor 11, a bistable 10 which is triggered each time the voltage of capacitor 11 reaches a given value so that capacitor 11 is discharged by a transistor 12, and a counter 6 which advances by one unit after a given number (e.g. one) of discharges of capacitor 11. The charging current of battery 1 may be monitored by a second such counting arrangement to allow the state of battery charge to be deduced, or one up/down counter may be arranged to indicate this. <IMAGE> |
