The application of unmanned aerial vehicles (UAVs) in the industrial sector is becoming more and more common, currently in the energy sector they are used to carry out the inspection of transmission lines and infrastructure of electrical networks. When transporting electrical energy, transmission lines emit extremely low frequency (60Hz) electromagnetic fields. This research work proposes the design, conceptualization, simulation and implementation of an electronic system that, when connected to the UAV, allows the detection of a magnetic field when performing visual inspection operations on electrical transmission lines. UAVs are described, the fields emitted by the transmission lines are studied, and finite element simulations are performed to evaluate whether the project can be viable. The objective is for the air vehicle to be able to determine the electric or magnetic field strength and communicate to the UAV flight controller the intensity to act and achieve self-protection from the effects of the transmission line fields.