SunSpec Modbus is a communication protocol which is based on a client/server architecture. The protocol offers easy and reliable communication between a client and one or more servers (in this case the inverters). Either a direct, serial connection via RS485 between devices is possible (Modbus RTU) or communication via a network (Modbus TCP). The manufacturer-independent data models defined by SunSpec Alliance contain parameters and settings for the monitoring and control of systems for decentralised energy resources (DER) at component level.