CHOPPERS AFFECT OPERATION OF AF TRACK CIRCUITS

Interference has been observed on US metros between the latest chopper-controlled trains and coded track circuits used for train detection as well as cab signals and ATO. The most dominant interference mechanism is inductive coupling between equipment carried on the car and the loop formed by the rails and axles under the car. Currents induced in this loop can result in transient "track clear" indications as a powered car passes over the impedance bond separating adjacent track circuits. A joint government-industry working group is developing ways of quantifying and controlling the problem.

  • Availability:
  • Corporate Authors:

    IPC Transport Press, Limited

    Dorset House, Stamford Street
    London SE1 9LU,   England 
  • Authors:
    • Frasco, L A
  • Publication Date: 1980-4

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 00316565
  • Record Type: Publication
  • Source Agency: British Railways
  • Files: TRIS
  • Created Date: Sep 16 1981 12:00AM