Open source embedded data logger design for PV system monitoring

The monitoring system in photovoltaic power generating system is very important and crucial in some cases for evaluating, troubleshooting and in decision making issue. This paper proposes very simple and low cost an embedded data logger with the high reliability and high precision for monitoring PV power generating system. The data logger meets all of the relevant requirements in terms of accuracy included in the International Electro technical Commission (IEC) standards for PV systems. The implementation process, including design and development of the hardware and software, is explained in detail. The electrical and meteorological sensor outputs are first conditioned according to microcontroller analogue to digital converter input needs using precision electronic amplifier and active filter circuits and then digitized and processed using 32 bit ARM Cortex M4 core microcontroller. Some sample deployment and measurement results are also presented to demonstrate the usefulness of the monitoring system.