Abstract: A remote contamination sensing device for contamination on insulation of electric power lines and substations includes a data logger and a supporting structure to which a sensing capacitor with at least two conductors is attached such that the conductors are spaced apart and insulated from each other. A capacitance measuring device, for measuring capacitance data between the conductors, is connected to the data logger. A hygrometer, for measuring the relative humidity of the ambient air, is also connected to the data logger. A first temperature sensor, for measuring the ambient temperature, and a second temperature sensor, for measuring the surface temperature of the capacitance sensor, are connected to the data logger. The measured capacitance data, relative humidity data, ambient temperature data, and surface temperature data are stored in the data logger.