| 摘要 |
PURPOSE:To establish small capacity of power failure compensating power supply, by counting the input pulses with the non-volatile counter at normal time and by performing count with electronic counter at the failure such as power failure, and by transferring this to the non-volatile counter after the power is restored. CONSTITUTION:The stator of the three wire type transmitter 8 is connected to RS type FE1, and counting is made by inputting the output of FF1 to the non- volatile counter 3 via OR gate 2. On mains failure, the control circuit 7 turns off the power supply for the counter 3 with the signal from the power failure detection circuit 6. To other circuits, power supply is supplied from the power failure compensation battery. Simultaneously, the selection circuit 4 is operated and the pulses from FF1 are counted with the electronic counter 5. When power is restored, the circuit 7 is operated with the circuit 6 and the power supply is fed to the counter 3. Also, pulses are fed to the counter in the circuit 7 until they are in agreement with the count value of the counter 5, and if they are in agreement, the value is fed to the counter 3. Accordingly, during power failure, count is made with the electronic type counter less in power consumption and the capacity of battery can be less. |
