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