Wyoming Administrative Code › Agency 053 - Workforce Services, Department of › Sub-Agency 0004 - Mining Inspector › Chapter 4 - UNDERGROUND COAL MINES › Subpart T - Diesel-Powered Equipment › Section 75.1910 - Nonpermissible diesel-powered equipment; electrical system design and performance requirements

Current through July 13, 2024
Electrical circuits and components associated with or
					 connected to electrical systems on nonpermissible diesel-powered equipment
					 utilizing storage batteries and integral charging systems, except for the
					 special category of equipment under Sec. 75.1908(d), must conform to the
					 following requirements:
(a) Overload
				  and short circuit protection must be provided for electric circuits and
				  components in accordance with Secs. 75.518 and 75.518-1 of this part;
(b) Each electric conductor from the battery
				  to the starting motor must be protected against short circuit by fuses or other
				  circuit-interrupting devices placed as near as practicable to the battery
				  terminals;
(c) Each branch circuit
				  conductor connected to the main circuit between the battery and charging
				  generator must be protected against short circuit by fuses or other automatic
				  circuit-interrupting devices;
(d)
				  The electrical system shall be equipped with a circuit-interrupting device by
				  means of which all power conductors can be deenergized. The device must be
				  located as close as practicable to the battery terminals and be designed to
				  operate within its electrical rating without damage. The device shall not
				  automatically reset after being actuated. All magnetic circuit-interrupting
				  devices must be mounted in a manner to preclude their closing by force of
				  gravity;
(e) Each motor and
				  charging generator must be protected by an automatic overcurrent device. One
				  protective device will be acceptable when two motors of the same rating operate
				  simultaneously and perform virtually the same duty;
(f) Each ungrounded conductor must have
				  insulation compatible with the impressed voltage. Insulation materials must be
				  resistant to deterioration from engine heat and oil. Electric conductors must
				  meet the applicable requirements of Secs. 75.513 and 75.513-1, except electric
				  conductors for starting motors, which must only meet the requirements of Sec.
				  75.513;
(g) All wiring must have
				  adequate mechanical protection to prevent damage to the cable that might result
				  in short circuits;
(h) Sharp edges
				  and corners must be removed at all points where there is a possibility of
				  damaging wires, cables, or conduits by cutting or abrasion. The insulation of
				  the cables within a battery box must be protected against abrasion;
(i) When insulated wires other than cables
				  pass through metal frames, the holes must be substantially bushed with
				  insulated bushings. Cables must enter metal frames of motors, splice boxes, and
				  electric components only through proper fittings. All electrical connections
				  and splices must be mechanically and electrically efficient, and suitable
				  connectors shall be used. All electrical connectors or splices in insulated
				  wire must be reinsulated at least to the same degree of protection as the
				  remainder of the wire;
(j) The
				  battery must be secured to prevent movement, and must be protected from
				  external damage by position. Batteries that are not protected from external
				  damage by position must be enclosed in a battery box. Flame-resistant
				  insulation treated to resist chemical reaction to electrolyte must be provided
				  on battery connections to prevent battery terminals from contacting conducting
				  surfaces;
(k) A battery box,
				  including the cover, must be constructed of steel with a minimum thickness of
				  1/8 inch, or of a material other than steel that provides equivalent
				  strength;
(l) Battery-box covers
				  must be lined with a flame-resistant insulating material permanently attached
				  to the underside of the cover, unless equivalent protection is provided.
				  Battery-box covers must be provided with a means for securing them in closed
				  position. At least 1/2 inch of air space must be provided between the underside
				  of the cover and the top of the battery, including terminals;
(m) Battery boxes must be provided with
				  ventilation openings to prevent the accumulation of flammable or toxic gases or
				  vapors within the battery box. The size and locations of openings for
				  ventilation must prevent direct access to battery terminals;
(n) The battery must be insulated from the
				  battery-box walls and supported on insulating materials. Insulating materials
				  that may be subject to chemical reaction with electrolyte must be treated to
				  resist such action; and
(o)
				  Drainage holes must be provided in the bottom of each battery box.