Code of Virginia (Last Updated:July 28, 2020) |
TITLE 45.1. Mines and Mining |
CHAPTER 14.3. Requirements Applicable to Underground Coal Mines |
ARTICLE 11. Electricity |
SECTION 45.1-161.186. Power circuits |
A. All underground power wires and cables shall have adequate current-carrying capacity, shall be guarded from mechanical injury, and shall be installed in a permanent manner. B. Wires and cables not encased in armor shall be supported by well installed insulators and shall not touch combustible materials, roof, or ribs; however, this shall not apply to ground wires, grounded power conductors, and trailing cables. C. Power wires and cables installed in belt-haulage slopes shall be insulated adequately and buried in a trench not less than 12 inches below combustible material, unless encased in armor or otherwise fully protected against mechanical injury. D. Splices and repairs in power cables shall be made in accordance with the following: 1. Mechanically strong with adequate electrical conductivity; 2. Effectively insulated and sealed so as to exclude moisture; 3. If the cable has metallic armor, mechanical protection and electrical conductivity equivalent to that of the original armor; and 4. If the cable has metallic shielding around each conductor, then the new shielding shall be equivalent to that of the original shielding. E. All underground high-voltage transmission cables shall be: 1. Installed only in regularly inspected airways; 2. Covered, buried, or placed on insulators so as to afford protection against damage by derailed equipment if installed along the haulage road; 3. Guarded where miners regularly work or pass under them unless they are 6 1/2 feet or more above the floor or rail; 4. Securely anchored, properly insulated, and guarded at ends; and 5. Covered, insulated or placed to prevent contact with trolley circuits and other low-voltage circuits. F. New high-voltage disconnects installed on all underground electrical equipment shall automatically ground all three power leads when in the open position. All high-voltage disconnects that are rebuilt or remanufactured after July 1, 2011, shall meet this standard. G. All power wires and cables shall be insulated adequately where they pass into or out of electrical compartments and where they pass through doors and stoppings. H. Where track is used as a power conductor: 1. Both rails of main-line tracks shall be welded or bonded at every joint, and cross bonds shall be installed at intervals of not more than 200 feet. If the rails are paralleled with a feeder circuit of like polarity, such paralleled feeder shall be bonded to the track rails at intervals of not more than 1,000 feet; 2. At least one rail on secondary track-haulage roads shall be welded or bonded at every joint, and cross bonds shall be installed at intervals of not more than 200 feet; and 3. Track switches on entries shall be well bonded. Code 1950, §§ 45-82, 45-82.1; 1954, c. 191; 1966, c. 594, § 45.1-78; 1993, c. 442; 1994, c. 28 ; 1996, c. 28 ; 1999, c. 28 ; 2005, c. 28 ; 2011, cc. 28 , 28 . |