Subchapter 5. Electrical Safety Orders
Group 2. High-Voltage Electrical Safety Orders
Article 6. Grounding (Formerly Article 55)

§2739. Grounding of Systems and Circuits--General.

(a) Grounding of high-voltage systems and circuits is permitted, but is not mandatory unless specifically required elsewhere in these regulations. Where high-voltage systems are grounded, the applicable requirements of this Article 6 shall apply.

(b) If the system is to be grounded, a grounding connection shall be made to the system neutral if available. This connection shall be made at or on the source side of the service entrance equipment.

(c) Grounding connections shall be arranged to prevent objectionable current in the equipment grounding conductor during normal system operation. The temporary current carried by the equipment grounding conductor during fault conditions, while the grounding system is performing its intended protective function, is not objectionable.

(d) Grounding equipment and connections shall have ample thermal capacity to carry safely any current which may be imposed on them by the system.

(e) Grounding connections shall be clamp type, pressure type, welded, or other approved type.

(f) Grounding electrodes shall be of corrosion-resistant material and of adequate size, number, and location to effectively ground the system.

(g) Local piping systems, well casings, building frames, and the like shall not be used as system grounding electrodes unless their resistance to ground will be maintained low enough to insure effective grounding.

(Title 24, Part 3, Section 3-250-150(a)-(g).)

(h) A system neutral derived from an adequately rated grounding transformer shall be permitted to be used for grounding a high-voltage system.

(Title 24, Part 3, Section 3-250-151.)

(i) High-voltage systems supplying portable high-voltage equipment covered by Section 2743 shall be grounded.

NOTE: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code; and Section 18943(c), Health and Safety Code.

HISTORY

1. Editorial correction including renumbering of former Article 55 to Article 6 filed 11-2-83 (Register 83, No. 45).

2. Amendment filed 12-10-87; operative 1-9-88 (Register 88, No. 1).