On-line automatic measurement of contact resistance of metal to carbon relays used in railway signaling

Abstract

The contact resistance of metal to carbon relays is a vital quality parameter. The manual measurement system is tedious, error prone and involves lot of time, effort & manpower. Besides, it is susceptible to manipulation and this may adversely affect the functional reliability of relays. To enhance the trustworthiness of CR measurement, an On-line automated measurement system having a testing jig attachment and specially designed software was developed. When the relay was fixed on the testing jig, the software measured the CR and results were ported on an internet website. Thus, accurate & reliable CR values were available in real time, easily and swiftly. © 2011 Springer-Verlag.