Applicability of Magnetic Sensors in Interlocking Systems

Rail interlocking systems follow the progress of technology and train speeds. Nowadays, new systems are designed based on microcontrollers and reliable software, requiring many hours of testing to ensure their proper functionality and bug-free coding. However, in many countries, there are still older relay solutions implemented that are not envisaged to be upgraded in the near future partially due to costs but mainly due to the fact they function very well, being based on a highly reliable element: the relay. However, specialized maintenance personnel are becoming more difficult to find, so automation systems that check the proper relay functionality are a key element to ensure a longer lifetime of existing systems. In this article, the authors present a monitoring solution based on magnetic sensors that proved capable of provide reliable information about the relays, hence revealing the first step in a relay automated control system.