[Code of Federal Regulations]
[Title 30, Volume 1]
[Revised as of July 1, 2006]
From the U.S. Government Printing Office via GPO Access
[CITE: 30CFR77]

[Page 649-650]
 
                       TITLE 30--MINERAL RESOURCES
 
  CHAPTER I--MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR
 
PART 77_MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK 
AREAS OF UNDERGROUND COAL MINES--Table of Contents
 
     Subpart J_Low- and Medium-Voltage Alternating Current Circuits
 
Sec.  77.906  Trailing cables supplying power to low-voltage mobile 
equipment; ground wires and ground check wires.

    On and after September 30, 1971, all trailing cables supplying power 
to portable or mobile equipment from low-voltage three-phase resistance 
grounded power systems shall contain one or more ground conductors 
having a cross-sectional area of not less than one-half the power 
conductor. Such

[[Page 650]]

trailing cables shall include an insulated conductor for the ground 
continuity check circuit except where a no less effective device has 
been approved by the Secretary to assure continuity. Splices made in 
low-voltage trailing cables shall provide continuity of all components.