TESTS MADE TO OBTAIN EXTENT OF TRACK CIRCUIT INTERFERENCE

Numerous tests have been conducted by the Southern Pacific to determine the source and paths that couple electrical frequencies of alternator equipped locomotives with various rail circuits. To date, it has been determined that both EMD and GE diesel electric locomotives which are alternator equipped, do induce a signal into the rails. These signals vary from below 0.25 mv to 31 mv at frequencies from 150 to 2376 Hz measured directly across the rails. Factors affecting the voltage measured at the rail or track circuit devices are numerous. Unbalanced track circuits, condition of ballast, ground resistance, capacitive action and other environmental conditions are all involved in coupling a locomotive produced frequency with track circuit devices.

• Corporate Authors:

  Simmons-Boardman Publishing Corporation

  P.O. Box 350
  Bristol, CT  United States  06010
• Publication Date: 1971-8

Media Info

• Features: Figures;
• Pagination: p. 16
• Serial:
  • Railway System Controls
  • Volume: 2
  • Issue Number: 8
  • Publisher: Business Press International Limited

Subject/Index Terms

• TRT Terms: Alternators; Diesel electric locomotives; Interference; Track circuits
• Identifier Terms: Southern Pacific Railroad
• Subject Areas: Operations and Traffic Management; Railroads; Vehicles and Equipment;

Filing Info

• Accession Number: 00041035
• Record Type: Publication
• Files: TRIS
• Created Date: Mar 9 1974 12:00AM