§ 690-332. Load center
Purdon's Pennsylvania Statutes and Consolidated StatutesTitle 52 P.S. Mines and MiningEffective: January 5, 2009
Effective: January 5, 2009
52 P.S. § 690-332
§ 690-332. Load center
Transmission voltage shall be reduced to machine utilization voltage by a portable transformer or load center of adequate capacity for the equipment powered by it. The transformer shall be of the dry type, ventilated, nonventilated or sealed, substantially constructed and completely enclosed in a metal case. The metal enclosure shall be connected to the high-voltage system ground conductor in the high-voltage cable. Complete load center construction shall render it essentially fireproof. In addition to these requirements, the following shall be observed:
(1) Connection of the high-voltage cable to the load center shall be made through a cable coupler of the type described in section 331(c).1
(3) The restriction of section 330(4)2 pertaining to transformer connections and use of zig-zag grounding transformers also apply to the load center.
(4) The transformer secondary neutral, direct or derived, shall be connected to machine trailing cable safety ground conductors through a ground current limiting resistor capable of limiting ground fault current to 25 amperes or less. The inby side of the resistor shall be grounded to the load center frame if no DC equipment powered from a common mine DC system can contact the frames of AC equipment powered by this load center. In the event there is a possibility of frame contact between AC equipment and DC equipment supplied from a common DC mine system, the inby side of the resistor may be insulated from the load center frame and shall be solidly connected to the DC ground system.
(5) The load center shall be equipped with a main secondary breaker of adequate interrupting capacity with tripping devices which shall feed individual machine breakers located either in the load center or external to it in a separate distribution center. External utilization voltage connections shall be made through receptacles arranged so that they cannot be uncoupled under load.
Credits
2008, July 7, P.L. 654, No. 55, § 332, effective in 180 days [Jan. 5, 2009].
52 P.S. § 690-332, PA ST 52 P.S. § 690-332
Current through Act 13 of the 2024 Regular Session. Some statute sections may be more current, see credits for details.
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