The working principle of the single-phase cost-controlled smart electric energy meter is that the measured AC voltage and current are sampled with high precision and sent to a dedicated electric energy metering chip. After a series of digital processing, they are converted into pulse frequency signals proportional to active power and sent to the microprocessor , The microprocessor will time-sharing and accumulate the pulse signal according to the time period charge rate to obtain the total power and the power of each charge rate, and save the results in the data memory. The microprocessor performs the functions of displaying and exchanging information with the outside at the same time.
Real-time calculation of electricity bill in the electric energy meter, its main functions include:
① When the remaining amount is less than or equal to the set alarm amount, the electric energy meter can remind the user by sound, light or other means; the overdraft amount should be recorded in real time. When the overdraft amount is lower than the set overdraft threshold amount, the electric energy meter will issue an off Electric signal, control load switch to interrupt power supply;
After the electric energy meter receives the effective renewal of electricity bill information, the overdraft amount is first deducted. When the remaining amount is greater than the set value (default is zero), the electric energy meter can be placed in the allowable closing state through remote or local methods. The power supply is restored locally.
②The remaining amount cannot exceed the maximum stored value of the electric energy meter allowed by the design; the maximum stored value is determined by the display digits of the electric energy meter.