Original General Order
Detailed Construction Requirements for Supply Lines
(Class H, L
and T Circuits)
57.8 Bonding and Grounding
The provisions of Rules 57.4, 57.6 and 57.7 for grounded cables, and grounded messengers, are applicable only to cables having metallic sheaths, and to messengers, which are effectively grounded at both ends of each run and at intermediate points not exceeding 800 feet apart. Where such a metal sheathed cable is supported on a messenger, each section of cable between splices shall be permanently bonded to the messengers at not less than two locations.
Cables not bonded and grounded as specified above shall conform to the requirements for unprotected supply conductors with the modifications provided in the several parts of Rule 57.