The development of innovative non-destructive testing (NDT) methods to improve the efficiency, reliability and safety in the railway transport system is a topic of the railway research. A new measurement system, based on infrared camera acquisitions is considered in this paper. The continuous sliding contact between the wire and the pantograph strip and break arcs leads to a temperature gradient. The quality of the current collection can be evaluated by monitoring the infrared emission at the contact point. Measurements carried out during high speed test runs and a post processing of the data collected have revealed the effectiveness of the proposed sensor for detecting the losses of contact, in order to evaluate and test the performance of running pantographs and of the contact wires