638 660.14 -CONDUIT : Conduit runs shown on the Plans may be changed to avoid underground obstruct ions with the written approval of the Engineer. Approximate lengths of conduit are shown on the Plans. The Contractor shall determine the exact lengths of conduit in the field. The ends of all conduits, whether shop or field cut, shall be reamed to remo ve burrs and rough edges. Cuts shall be made square and true so that the ends will butt or come together for the full circumference thereof. Standard conduit couplings shall be used for joining all metal conduit. Slip joints or running threads will not be permitted for coupling conduit. However, expansion fittings shall be installed where the conduit crosses an expansion joint on a structure. Continuity through the expansion fitting shall be provided by means of # 6 AWG copper wire jumper. Conduit run s on the surface of structures shall be secured with galvanized malleable iron clamps spaced not more than five ( 5) feet apart. The threads on all ferrous metal conduit shall be painted with rust preventative paint before couplings are made up. All coupl ings for metal -type conduit shall be tightened until the ends of the conduit are brought together, providing a good electrical connection throughout the entire length of the conduit run. Where the coating on metal conduit has been damaged in handling or installing, such damaged places shall be painted with an approved rust preventive paint. Exposed ungalvanized threads on metal conduit resulting from field cuts shall be painted with an approved rust preventative paint. All metal -type conduit ends shall b e threaded and shall be capped with a standard pipe caps until wiring is started. When caps are removed, the threaded ends shall be provided with conduit bushings. Conduit bends, except factory bends, shall have a radius of not less than six times the in side diameter of the conduit. Where factory bends are not used, conduit shall be bent, without crimping or flattening, using the longest radius practicable. A # 12 AWG galvanized pull wire shall be installed in all conduits which are to receive future co nductors. At least two ( 2) feet of pull wire shall be doubled back into the conduit at each termination. All conduit runs shall be free of dirt, debris and excessive moisture before cable is pulled. Existing underground conduit to be incorporated into the new system shall be cleaned with a mandrel or cylindrical wire brush and blown out with compressed air. Conduit shall be laid to a depth of not less than eighteen ( 18) inches below finished grade in all areas, except that conduit may be laid on top of and secured to the existing pavement within new curbed medians being constructed on top of the pavement. Rigid metal conduit shall be placed under existing pavement by approved jacking or drilling methods. Pavement shall not be disturb ed without permission from the Engineer. In the event obstructions are encountered, upon approval of the Engineer, small test holes may be cut in the pavement to locate obstructions. Jacking or drilling pits shall be kept two ( 2) feet clear of the edge o f any type of pavement wherever possible. Water jetting will not be permitted. Conduit terminating in pile or pedestal bases shall extend four ( 4) inches vertically above the foundation and shall be sloped towards the hand -hole opening. At all conduit t ermini, the conduit shall enter the outlet from the direction of the run. Conduit size shall be the same for terminal point to terminal point. No reducing couplings will be permitted. If it is determined by the Engineer that it is impractical to bore th e conduit under concrete or asphaltic pavement due to unforeseeable obstructions, the Contractor may, with the Engineer's permission, cut the existing pavement. The pavement shall be cut along neat and true lines by means of a concrete saw. The depth of the trench shall be as specified and the width shall be the minimum required for proper excavation and backfilling. The trenching operation, along with 639 replacement operation, shall be performed according to Standard Detail TES -04. Concrete shall be allow ed to set for a minimum of 49 hours without being exposed to traffic. At no time shall more than one -half of the roadway be closed for any conduit placement operations. Conduit to be placed beneath railroad tracks shall comply with the following: The co nduit shall be rigid metal type, two ( 2) inches minimum size and shall be placed to a minimum depth of five ( 5) feet below the bottom of the tie. The near side of each conduit jacking pit shall be constructed not less than twelve ( 12) feet from the center line of track. When the jacking pit is to be left overnight it shall be covered with substantial planking.
660.15 Junction Boxes :
Junction boxes shall be installed at the locations shown on the Plans or, in long runs, they shall be spaced at not over 200 feet intervals. The Contractor may, at his own expense and with the approval of the Engineer, install additional junction boxes to facilitate his work The tops of junction boxes installed in the ground or in sidewalk areas shall be flush with the surrounding grade or pavement. Concrete junction boxes shall be poured in place. However, pre -cast junction boxes may be used, when in the opinion of the Engineer, the surrounding subgrade has sufficien t bearing qualities to support the box and cast iron frame. All junction boxes shall be set on at least twelve ( 12) inch bedding of aggregate base material as shown on the Plans. Grouting shall be done prior to the installation of conductors. No junctio n boxes shall be set on uncompacted ground. Concrete work shall be done in accordance with the applicable requirements of subsection 660.8. The Contractor shall be responsible for reconstruction and/or replacement of all damaged junction boxes. Damage junction boxes shall be defined as any junction box more than two (2) inches below grade, or is covered by the area roadway surface. The adjustment of the junction box shall include the complete excavation and shall conform to Specifications, Secti on 660.8 and 660.15. All conduit, cable and attached appurtenances shall be incidental to this junction box. The adjustment of the junction box shall be as per detail and shall conform to Specifications Section 660.8 and 660.15.
660.16 Wiring :
Sufficient five -conductor signal light cables shall be provided to perform the functional operation of the signal system and, in addition thereto, one spare conductor of a size equal to the largest signal light conductor in th e run, except neutral, shall be provided throughout the signal light system. No more than two signal heads shall be on the same conductor run. When two signal heads are on the same conductor run, they must be of the same signal color sequence. All signa l light conductors shall be run continuously without splices from the terminal block located in a cabinet, compartment, or signal head, to a similarly located terminal block, unless otherwise specified on the Plans. Signal light conductors shall not run t o a terminal block on a standard unless they are to be connected to a signal head that is mounted. All spare wires shall be placed on a special terminal block mounted in the controller cabinet for this purpose. Five-conductor IMSA cable as specified shal l be provided for all signal light circuits. This cable shall consist of red, orange, green, black and white insulated wires. The insulation color shall correspond as nearly as possible to the associated signal sequence color.