641 requirements of Military Specification MIL -T-7928. Splices shall be insulated by one of the following methods:
i.Cast insulation of self -curing epoxy resin which is compatible with the wire insulation to form a moisture resistant joint. The resin shall be resistant to weather, with aromatic, straight chain solvents, and shall not sustain combustion. The resin shall be cured into molds of dimensions suitable for the splice. ii. A minimum of two thicknesses of electrical insulating pad, composed of a laminate of 0.085 -inch thickness of electrical grade polyvinyl chloride and a 0.125 -inch thickness of butyl splicing compound with removable l iner. Pads shall be applied to the splice in accordance with the manufacturer's recommendations. The ends of the applied pad shall be wrapped with the polyvinyl chloride tape half lapped over the conductor insulation. iii. Heat shrinkable insulating tub ing shall be applied after completing the splicing procedure shown on the Plans. Insulation over the connector shall consist of a heat shrinkable, mastic lined, heavy wall polyolefin cable sleeve or cover, to which heat shall be applied at a temperature g reater than 120EC until the sleeve or cover shrinks and covers the connector, and the mastic material has flowed completely around the cable to form a waterproof insulation. Electrical tape shall be UL approved and be one of the following types:
i.Self-fusing, oil and flame -resistant, synthetic rubber. ii. Pressure sensitive, adhesive, polyvinyl chloride, 0.007 inch minimum thickness. Where polyvinyl chloride tape is used for a final layer, an electrical insulating coating shall be used which sha ll be fast drying, resistant to oil, acids, alkalies and corrosive atmospheric conditions and compatible with the tape. All splices shall be noted on the Plans and approved by the Engineer. Unless otherwise specified, shown on the Plans or directed by th e Engineer all signal system conductors shall run continuous and unspliced from terminal to terminal. Signal system conductors shall include but not be limited to power service wires, signal circuit conductors, controller panel wiring, controller wire har ness, loop lead -in and loop wire. System interconnect cable shall be continuous and unspliced from controller cabinet terminal to controller cabinet terminal.
660.17 Power Service :
The power connection shall be made to a single -phase 120/240 volt, three -wire, 60Hz, AC supply. The approximate location of utility service points may be shown on the Plans; however, the Contractor shall determine the exact location of the power supply. Each signalized intersectio n or control unit shall have a separate power service and no more than one power service shall be utilized per intersection or unit. Electrical service installation and materials shall conform to the requirements of the serving utility. The service equip ment shall be installed as soon as possible to enable the utility to schedule work well in advance of the completion of the project. Enclosed circuit breakers, external to the controller cabinets, shall be provided in the power service. Four single -pole breaker units rated at 30 amps each are required. The breaker enclosure shall be weathertight with a top hinge cover, hasp for sealing cover and provisions for padlocking the cover. The Contractor shall provide an all -weather padlock and two sets of keys with each power service. Circuit breakers shall be approved and listed by the Underwriter's Laboratory. 642 Breakers # 1 and 2 shall provide power for the signal control equipment (controller cabinet). Specifically circuit breaker # 1 shall power the controller circuits and # 2 shall power the flasher and associated circuitry. These two circuits must be of the same polarity. Breakers # 3 and 4 are spare terminals to accommodate future lighting circuits and breakers 3 and 4 must be of opposite polarit y to provide a 240 volt circuit. The Contractor shall make all arrangements for connection to the power supply and shall obtain a meter and meter socket from the power company at the time these are required. The Contractor shall furnish, install, pay ins tallation fee and provide all materials necessary for the power connection not provided by the power company. All external power service wiring from the service head or service point on shall be enclosed in rigid metal conduit; this includes equipment gro und wires. When complete and in place the power service shall provide in the signal controller cabinet, two separate fused 120 VAC, 60 Hz power sources rated at 30 amps each of the same polarity or phase.
660.18 Testing :
660.18.1 Operational Field Tests: Upon completion of the installation of a traffic signal
system, operational field tests shall be run on each and every part of the system. After the initial field tests are run satisfactorily, the Contractor shall conduct a continuous 12 -hour operating test for approval. Upon successful completion of the 12 -hour test and with the approval of the Engineer, a 30-day test period will then be initiated. Final acceptance of an installation will not occur until 30 days of system operation are completed and termed satisfactory by the Engineer. A final inspection may be conducted by the Division at any time prior to completion of the 30-day test. At the option of the Engineer, equipment found to be defective during this inspection may warrant the renewal of the full or any part of the operational test period. In addition, the Contractor shall be responsible for equipment malfunctions that occur during any test period. The Contractor shall repair or replace any defective equipment within 24 hours after bei ng notified by the Engineer. After the repair has been effected, the Engineer may at his option renew any or all of the operational test period.
660.19 Method of Measurement :
660.19.1 Signal Controll ers: Signal controllers shall be measured as a complete unit in
place by intersection or control location. This item shall consist of the complete electrical mechanism for controlling the operation of traffic control signals, including the timing mechani sm and all necessary auxiliary equipment mounted in a cabinet or other enclosure. Included under signal controllers shall be traffic adjusted master controllers and computers and associated equipment. This item shall include cabinets or other enclosures as required.
660.19.2 Detectors :
660.19.2 1-Traffic Detectors: Traffic detectors shall be measured per unit complete
and in place, mounted in a cabinet or enclosure as required. This item shall consist of the detector tuning unit only. The roadway traffic sensors, such as loops, and associated cables outside of cabinet, shall be included in "Miscellaneous Signal" items. Any supplementary cabinets or other enclosures as required for the detector tuning units shall also be included in "Miscel laneous Signal".
Source: West Virginia Standard Specifications for Road and Bridge Construction, 2023 Edition. Pages 661–662 of 1,006.