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Specifications. One continuous, unbroken length shall be used to form a loop of the <br />number of turns required and the lead-in from loop to junction box. <br />L. The lead-ins from the detector shall be Type B, lead-in cable shall be insulated with 20 <br />mils of high-density polyethylene. The conductors shall be twisted together with at least 2 <br />turns per foot and the twisted pair shall be protected with a copper or aluminum polyester <br />shield. A No. 20, minimum, copper drain wire shall be provided and connected to the <br />equipment ground within the cabinet. The cable shall be provided with a high-density <br />polyethylene or high-density polypropylene outer jacket with a nominal thickness of 32 <br />mils. An amorphous interior moisture penetration barrier of nonhydroscopic polyethylene <br />or polypropylene fillers shall be provided in accordance with Section 86-1.02F(2)(c)(iii) <br />"Inductive Loop Conductors" and 87-1.03V(2) "Inductive Loop Detectors". The lead-in <br />shall be spliced, soldered and taped to the loop at the junction box. The shield shall be <br />connected to the controller cabinet ground bus. Where spade terminals are used to <br />secure the lead-in wire to field terminal blocks, the spade terminals shall be soldered as <br />well as crimped to the OF wire. All detector lead-in cable shall be continuous - no splicing <br />is permitted. <br />M. After the loop conductors are installed in the pavement, the slots shall be filled to within <br />1/8" of the pavement surface with the appropriate sealant. All excess shall be removed. <br />N. Detector loop lead-ins shall be installed in conduit from the gutter to the splice box. After <br />installation of loop wires, gutter end of conduit is to be sealed with duct seal and excavation <br />is to be filled with sand to within 1-1/2" of road surface and capped with asphalt. <br />O. All splices shall be soldered to ensure constant low resistance and must be insulated in <br />such a manner that the installation maintains resistance to ground of not less than 100 <br />megaohms. To ensure that the loop installation is correct, a continuity check of the loop <br />writing and a resistance check of this loop -to -ground shall be performed using a "megger" <br />or other suitable insulation tester, with a representative of the City Engineer present. Loop <br />readings that decrease below 20 megaohms during the guarantee period shall be <br />considered below minimum limits and shall require replacement. <br />P. The contractor shall test the detectors with a motor -driven cycle, as defined in the <br />California Vehicle Code, that is licensed for street use by the Department of Motor Vehicles <br />of the State of California. The unladen weight of the vehicle shall not exceed 200 pounds <br />and the engine displacement shall not exceed 100 cubic centimeters. Special features, <br />components or vehicles designed to activate the detector will not be permitted. The <br />contractor shall provide an operator who shall drive the motor -driven cycle through the <br />response or detection area of the detector at not less than three (3) miles per hour nor <br />more than seven (7) miles per hour. The detector shall provide an indication in response <br />to this test. <br />Q. Chevron asphalt loop sealant or equal shall be used. <br />R. Adjacent loops shall be tied to the same four -channel detector. <br />S. The number of lead -in -cable required to achieve the specified detection shall be installed. <br />T. Where Type "A" loops are indicated on the plans, except for speed monitoring installation, <br />a six-foot diameter circular loop may be installed in lieu of the shape shown on the plans. <br />The sides of the slot shall be vertical and the minimum radius of the slot entering and <br />leaving the circular part of the loop shall be 1-1/2 inches. <br />U. If any part of the loop conductor, including the portion leading to the adjacent pull box, is <br />damaged by the contractor's operations, the entire detector loop shall be replaced. If any <br />adjacent loop is damaged during such replacement, that loop shall also be replaced. <br />REV: 12-21-2020 PR <br />ATTY/AGR.2020.306/Bear Electrical Solutions (Page 33 of 35) <br />