StacksVerified U.S. regulatory reference

30 CFR §75.701-3

Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗
For the purpose of grounding metallic frames, casings and enclosures of any electric equipment or device-receiving power from a direct-current power system with one polarity grounded, the following methods of grounding will be approved:
  1. (a)A solid connection to the mine track;
  2. (b)A solid connection to the grounded power conductor of the system;
  3. (c)Silicon diode grounding; however, this method shall be employed only when such devices are installed in accordance with the requirements set forth in paragraph (d) of § 75.703-3; and
  4. (d)Any other method, approved by an authorized representative of the Secretary, which insures that there is no difference in potential between such metal enclosures and the earth.