The concept of power harvesting works towards the development of self-powered devices not requiring replaceable power supplies. The increase in power used by the electronics has led to a reduction in battery life and has limited the functionality of the devices. In an effort to extend the life and to reduce the volume of the electronics, researchers have begun investigating methods to obtain energy from the ambient energy surrounding the device. In this work the authors focused on the characterization of a piezoelectric vibration harvesting device to be applied in a train derailment detector system, in which the harvesting device supplies the wireless transmission unit sending warning messages to the trains driver. In what follows the attempt to harvest energy by means of a specific architecture to be placed, according to the project specifications, on the train gear, is presented.