Wireless system for detecting high intensity current impulses applied to ground grids

Grounding system is an essential element for personal and electrical installations safety; for this reason, it is very important to evaluate the grid operational conditions. To draw a diagnosis of a ground grid it is necessary to determine its electrical characteristics both in industrial frequency and in surge conditions. The electrical characteristics are obtained from the injection of electrical current in the grid and its propagation effects are measured, i.e, several voltage signals are acquired at different points of the ground. The signal analysis is fundamental for the adequate evaluation of the grounding system operational conditions. This paper presents the development of a data acquisition system for assessment of grounding systems operational conditions when the grid is subjected to electrical current surges. The system is portable and capable to transfer data voltage signals acquired at different points of the ground employing a wireless network. The data acquisition system is based on a dsPIC 30F3011 microcontroller. The system has been tested and validated by using an impulse generator with an 11 kV capacitor charging. The system can be used to evaluate the degradation of the grounding grid and provide a predictive diagnosis.