Cameroon has a high potential for numerous energy resources. However, the country still relies heavily on hydropower (approximately 88%) as primary source of electricity. In spite of this high concentration on hydro, the generated energy is still very insufficient. As a consequence, the country is plagued by several electricity challenges, with approximately ten electrical outages per month, which last for an average of two hours. In this light, the country is currently investigating on the effective exploration of alternative energy sources. Among the energy resources being sorted, solar energy is the most abundant, clean, and renewable source available. PV system performance are largely dependent on location and operating conditions. Considering the heavy reliance on weather conditions, the close monitoring and evaluation of such a system can provide information on short-term or long-term corrective measures. In the context of Cameroon, it is extremely difficult to have access to reliable PV data. This is due to the high cost of PV measurement equipment or the acquisition of satellite weather data whose reliability and accuracy are still questionable. To overcome such challenges, this paper introduces a Trio-PV-systems monitor for consistent and continuous monitoring of PV systems. The Trio device is a smart system that embody an electronic hardware, desktop application and a website. The system is especially designed to provide consistent monitoring, storage, sharing as well as analytical power to engineers and scientists on solar energy related data at any chosen site. The overall system features high flexibility, with wide range weather-proof sensors, permitting the monitoring and evaluation to cut across seasons and different geographical areas. Additionally, the system is suited for PV plants of up to 100KW rating. The automated design of the system allows it to consistently operate for 12 hours within a day. In addition, the system is grid-energy independent, thus the control unit has continuous power to consistently operate the sensors and collect the data for storage and sharing. Therefore, the proposed IoT -based system is aimed at providing a reliable and continuous monitoring of the PV parameters, including PV voltage, current and power, the ambient and module temperature, the relative humidity and irradiance. The Trio-PV-system monitor has been tested and evaluated on a twelve-hour basis. The acquired results revealed satisfaction and consistency between the data collected on the desktop and that displayed on website. Graphs showing the evolution of each parameter with time can be viewed directly by use of the graphical interface provided on the desktop application. The production parameters on the chosen site can be evaluated at any location in the world by authorized users. This system will be of great use in developing countries, especially Cameroon where access to information on PV systems is costly.