For solar PV applications, RS-485 communications are used due to inherent noise immunity. Adding iCoupler isolated RS-485 transceivers provides a safe, reliable, and EMC robust solution for solar PV network communication interfaces.
RS-485 has several uses, the primary use being remote monitoring of power generation, power point trackers, and energy storage status (battery storage). For solar applications like energy storage communications is critical, as it alerts the user of power generation and consumption activities within their solar installation. Several systems strategies may be installed such as bill management, PV self-consumption, demand charge reduction, and backup power. Backup power is the most popular, especially in the U.S., due to the various hurricanes causing havoc in the states of Texas and Florida.
Solar generation, energy storage, and domestic consumption in a typical, 24-hour day is illustrated in figure 1. It is the primary reason why systems are designed for bill management in a solar system. During night time when there is no irradiation on the solar panel, energy consumed will be purchased from the grid where the grids are lowest. As soon as the sun rises irradiation appears on the solar panels, power is generated, and domestic self-consumption begins where any solar generation is either used in the household or is diverted to charge the energy storage unit. This allows bill costs to be controlled by reducing the energy drawn from the grid and using solar generated energy where low feed-in tariff areas are available from utility companies.