please provide me the correct circuit diagram of this project.

Most of the energy meters are designed to bill as per the units of energy consumed. These meters need to be manually read by people in order to provide monthly/quarterly bills. We here propose a prepaid energy billing meter. The system is designed to allow amount of energy to be used as long as the account has balance pending. It also allows the operator to recharge the user account using GSM. The system first accepts account recharge and allows to use only limited units of energy as per recharge and then cuts off the supply. The prepaid electricity billing meter could be widely used to provide a new more customized electricity billing system, where users may recharge when they intend to use that facility. It also consists of a GSM modem that allows the operator to recharge the meter remotely using am SMS message. This puts forward an innovative electricity billing and “use as needed” electricity usage scheme. It also eliminates the need for manual electricity meter reading tasks.