Development Of The Energy Management Terminal Unit Based On Dual MCUs

In the electric energy billing system, Energy Management Terminal Unit (Its acronym EMTU is used in the following) is the middleware between main station and rates devices(Power Meter),It has main functions of electric energy data acquisition,processing,storing,transmitting and infrared communications, and so on. Sampling is required sometimes. According to the differences of rates devices, EMTU acquires data from Power Meter by the way of electricity statute or pulse periodically. The data will be Stored selectively, meanwhile, It provide the real-time or historical data to master with the format and content that is fit for the metering master.In recent years, with the development of GPRS technology, Its application is grew rapidly. It has characteristics with flow-on charges, always-online, transmission stability. The embedded GPRS communications module is designed based on our research. This paper designs EMTU with the core MCU MSP430F449 (hereinafter referred to F449) and the supplemented MCU MSP430F2012 (hereinafter referred to F2012).Furthermore, the idea that updating the main MCU's programs by GPRS communications module online solves the old problem that updating programs is difficult in old ways. This paper focuses on the hardware and software of EMTU,the principle of remote on-line update and implementation, infrared communication theory and switching current range idea.The terminal has been put into operation in the northeastern region, the system runs stable, with good performance,cost-effective,good economic returns.