INDUCTIVE LOOP DETECTORS: THEORY AND PRACTICE

The need for an easily installed and relatively inexpensive system to provide passage and/or presence detection for traffic control purposes has led to substantial use of an inductive loop system. In the past, a lack of standardized performance criteria has hampered the design, installation, and maintenance of loop detector systems and resulted in a considerable amount of experimentation during the installation phase. This Implementation Package provides a users manual for design application and performance testing of inductive loop detector systems developed by the Department of Traffic, City of Los Angeles, California. It is based on a study of many of their approximately 3,000 loop detector field installations. The purpose of the study was to determine the causes of failure or intermittent operations and to develop aids for the design, test, and maintenance of these systems. Basic theory of loop detector operation is also presented along with a discussion of loop size and shape. Installation procedures used in the Urban Traffic Control System (UTCS) in Washington, D.C., are presented with other discussions of practical ways to deal with the installation of loops across pavement joints. A detector trouble-shooting procedure, with detail instructions and data recording forms, is presented in the Appendix in a form suitable for removal and use by individual technicians.

• Record URL:
  • https://rosap.ntl.bts.gov/view/dot/68056
• Corporate Authors:

  Pinnell-Anderson-Wilshire and Associates, Inc

  7540 LBJ Freeway, Suite 707
  Dallas, TX  United States  75251
• Authors:
  • Pinnell, C
• Publication Date: 1976-1

Media Info

• Media Type: Digital/other
• Features: Appendices; Figures; Photos; References; Tables;
• Pagination: 107 p.

Subject/Index Terms

• TRT Terms: Building; Design; Facilities; Installation; Loop detectors; Maintenance; Manuals; Performance tests; Sealing; Undersealing; Vehicle detectors
• Uncontrolled Terms: Design criteria
• Subject Areas: Construction; Design; Highways; Maintenance and Preservation; Operations and Traffic Management;

Filing Info

• Accession Number: 00135917
• Record Type: Publication
• Report/Paper Numbers: FHWA-RD-IMP-76-2 Final Rpt.
• Contract Numbers: DOT-FH-11-8123
• Files: NTL, TRIS
• Created Date: Sep 4 1976 12:00AM