1. Advances in EMC Measurements on Railways

2. Origins of EMI in Railways

3. Difficulties With Railway EMC Measurements (Fast) Moving EUT Large EUT Complex Radiation Propagation Mechanisms Poor Control of Measurement Environment Transient Emissions –from traction motors –from power supply arcing

5. The Measurement System Three Spectrum Analysers giving: –constant monitoring of a chosen frequency range Two Further Spectrum Analysers: –to detect transient emissions (amplitude & repetition) –set to single frequency (zero span) –wide input bandwidth –two analysers allow for test site variations and spurious radio signals Camera: –to record an image associated with each plot

6. Transient Detection Tuned Receiver / Spectrum Analyser –good dynamic range –readily available in EMC laboratories –good response when wide bandwidths chosen Fast Sampling Oscilloscope –All signal information can be captured instantaneously

15. Variations in Emissions

16. The System Aids In: Measurement of EM emissions from railway systems dynamically Separation of continuous and transient events –Increasingly important as digital communications become more widespread Rapid assessment of rolling stock characteristics Monitoring and assessing variations and degradations