A Low-Cost Dual-Processor IoT Testbed for Real Time PV Monitoring: Fault Emulation and Threshold-Based Alerting

Currently, commercial single chip IoT monitors used in PV education have problems with ADC noise from the built-in Wi-Fi and expensive/unpredictable PV arrays. In this paper, we introduce a second processor-based testbed for emulating PV in off-grid settings, which is built with minimal cost. The major innovation here is the decoupled design, which uses an Arduino Nano (ATmega328P) to process analog signals (voltages, currents, temperature, irradiance) so that analog signals are not corrupted by digital signals created by the ESP32’s WIFI. In addition to passive loggers, Solar Sync has controlled fault injection capabilities to simulate partial shading, overcurrent and thermal drift in a lab environment. It was tested for 96 hours under a 2W resistive load, and was highly stable (avg 12.06V, low SD) and delivered MQTT data to a web dashboard that has real-time graphing and automatic alerts. The platform is AI ready and has a cost of less than $45 and it connects between Renewable Energy theory and hands on IoT training, giving resource constrained academic labs an accessible, repeatable solution.