Change List for this Rule

 

General Order 95

 

Section IX

 

Joint Poles or Poles Jointly Used


92.4    Grounding

 

A.    General

The following rules cover the grounding or isolating of communication cable systems, as defined herein. Systems include cables, messengers, and guys, or a combination of these facilities at the supply or communication level.

The term “cable” means stranded conductor or a combination of conductors that includes Fiber Optic Supply Cable, Fiber Optic Communication Cable, or Non–Dielectric Fiber Optic Cable as defined in
Rule 20.4 .

The term “messenger” is defined in
Rule 22.3 .

The term “guy” is defined in
Rule 21.5 . The definition of “exposed” as applied to a guy in Rule 21.5–C shall also apply to cables and messengers.

 

B.    Applicability

The grounding of exposed communication cable systems includes cables with metallic shields, sheaths, or messenger(s). The isolating of exposed guys includes both overhead and anchor guys. Exposed communication cable systems are those that are subject to power contacts, power induction, or lightning. Cables, messengers, or guys are subject to power contacts and power induction if they:

 

(1)     Are attached to the same pole as a supply conductor; or

 

(2)     Cross a supply conductor; or

 

(3)     Are within 8 feet horizontally and any distance vertically of a supply conductor(s); or

 

(4)     Are attached to the same pole which supports an existing exposed messenger or guy, even though that pole does not support supply conductors of more than 250 volts.

 

C.    Material and Size

 

(1)    Grounding Conductors: The grounding conductors of the communication messenger system shall conform to each of the following requirements:

 

a)    The grounding conductor from each ground rod (ground electrode) to the base of the pole shall not be less than 1 foot below the surface of the ground.

 

b)     The conductor from each ground rod (ground electrode) to the base of the pole shall not have less ampacity and mechanical strength than the grounding conductor from the base of the pole to the messenger.

 

c)     The grounding conductor from the ground rod (ground electrode) to the messenger shall be continuous, unless suitable electrical compression connections are used.

 

d)     The grounding conductor shall have a minimum ampacity equivalent to No. 6 AWG copper.

 

(2)    Ground Rods (Ground Electrodes): Ground rods on the communication messenger system(s) shall conform to each of the following requirements.

 

a)    Ground rods shall be corrosion–resisting metal rods or pipes (or equivalent in electrical properties)

 

b)    Ground rods shall not be less than 5/8–inch in diameter by 8 feet (total) in length; this may include two (2) four–foot joined sections.

 

c)    Ground rods shall be driven into the ground so that one end of the ground rod is at a minimum depth of 8 feet below the surface of the ground. The top end of the ground rod shall not be less than 1 foot below the surface of the ground.

 

d)    Pole–butt plates or wrappings shall not be used either in lieu of the aforesaid ground rods or pipes, or as electrodes supplementary thereto.

 

e)    The driven ground rod(s), pipe(s), or equivalent shall be located 24 inches or more from the surface of the pole.

 

D.    Location of Grounds on Exposed Cables with Metallic Shields, Sheaths, or Messengers; and on Exposed Guys

 

(1)    Exposed Cables and Messengers: The exposed communication cables and messengers shall be grounded:

At all deadend poles and at intervals not greater than every one–quarter of a mile (1320 feet).

 

(2)    Exposed Guys: Communication guys exposed to supply conductors energized at 22,500 volts or less shall be insulated. Also, see Rules 86.6 , 86.7 and 86.8 .

The grounding of exposed cables, messengers, and guys is in addition to the ground connections at individual services.

Grounding of exposed messengers near supply electric substations may be constrained by technical requirements with cooperation between supply and communication companies.

 

Note:    Added October 9, 1996 by Resolution SU–40.