TRAFFIC COUNT CAPABILITIES OF FISCHER AND PORTER TAC-DET LOOP DETECTORS AND CARD KEY SYSTEMS TRANS-SENSOR DETECTORS

THIS STUDY COMPARES THE OPERATIONAL CHARACTERISTICS, PRECISION, INSTALLATION PROBLEMS AND COSTS OF THE TAC-DET LOOP VEHICLE DETECTOR AND CARD KEY SYSTEMS TRANS-SENSOR DETECTOR AT AN EIGHT LANE FREEWAY LOCATION. THE TRANS-SENSOR IS A MAGNETIC TYPE VEHICLE DETECTOR WHICH HAS GIVEN QUITE SATISFACTORY PERFORMANCE IN BOTH LABORATORY AND FIELD TESTS. THE FIELD EVALUATION CONSISTED OF COMPARING THE TRANS-SENSOR DETECTOR COUNTS WITH DIRECT ON-SITE OBSERVATIONS AND WITH AN ADJACENT INSTALLATION OF THE WIDELY USED FISCHER & PORTER TAC-DET LOOP DETECTOR. TRANS-SENSOR PERFORMANCE IN THESE TESTS WAS SOMEWHAT BETTER THAN THAT OF TAC-DET. TWO OF THE FACTORS RESPONSIBLE FOR THE TRANS-SENSORS SUPERIOR PERFORMANCE ARE AS FOLLOWS' /1/ THE TRANS-SENSORS GREATER LATERAL SPACING BETWEEN DETECTOR UNITS IN ADJACENT LANES PRODUCED FEWER DOUBLE COUNTS FROM LANE CHANGING VEHICLES, AND /2/ THE TRANS-SENSOR WAS EQUIPPED WITH AN ADJUSTABLE TIME HOLDING CIRCUIT THAT PREVENTS THE RELAY CONTACTS FROM BREAKING BETWEEN A TRACTOR AND TRAILER OF A TRUCK RIG. THE TRANS-SENSOR THUS PRODUCED FEWER MULTIPLE COUNTS OF COMBINATION VEHICLES. INSTALLATION PROCEDURES FOR THE TWO DETECTORS ARE DESCRIBED AND COMPARED ON A TIME BASIS. THIS TIME COMPARISON IS THEN PROJECTED TO A COST COMPARISON PER STATION FOR CONCRETE AND ASPHALT PAVEMENT. /BPR/

  • Supplemental Notes:
    • Hpr-1/4/, C-1-2 /STATE/
  • Corporate Authors:

    California Division of Highways

    Bridge Department
    Sacramento, CA  USA  05914
  • Authors:
    • Wasser, C F
  • Publication Date: 1966-9-14

Subject/Index Terms

Filing Info

  • Accession Number: 00219665
  • Record Type: Publication
  • Source Agency: Bureau of Public Roads /US
  • Files: TRIS
  • Created Date: Oct 1 1994 12:00AM