General Order 95
Section V
Detailed Construction Requirements for Supply Lines
(Class H, L and T Circuits)
54.6 Vertical and Lateral Conductors
A. Unprotected Conductors (See
Rule 20.9–E
for definition)
Unprotected conductors may pass laterally on a pole or structure
or vertically from one level on a pole or structure to another level, but
shall not pass within the climbing space; shall not pass within the working
space, except as permitted by Rule 54.7–B2
; shall not pass between conductors of any other circuit, except between
pole–pin conductor positions; and shall clear the conductors of other circuits
by distances not less than the following:
|
Highest Voltage Classification of Conductors Concerned |
Minimum Radial Distance between Conductors |
|
0 - 5,000 Volts |
11.5 inches |
|
5,000 - 7,500 Volts |
17.5 inches |
|
7,500 - 20,000 Volts |
24 inches |
|
20,000 Volts and above |
36 inches |
EXCEPTION: The minimum radial distances in this rule shall not apply to uncovered, grounded, non-dielectric fiber optic cables in transition on metallic structures, which must comply with Rule 38, Table 2, Case 16a.
Where unprotected vertical conductors are in excess
of 12 feet in length, additional supports shall be installed so that the
maximum length of conductor between supports is not more than 12 feet.
The clearances in the above tabulation do not apply between taps in buckarm
construction, the clearances specified in
Table 2, Case 16
, being directly applicable.
For clearances between street light drop wires and cables, other conductors
and metal boxes, see Rules 58.5–B3
and 92.1–F5
.
Unprotected conductors, installed as specified in this rule
(54.6–A)
and in Rule 54.4–D9
are not vertical or lateral runs as defined in
Rule 22.6
.
In lieu of the foregoing, vertical and lateral conductors may be installed
as specified in Rules 54.6–C
and 54.6–D
.
Note: Revised January 6, 1968
by Decision No. 73455 and October 9, 1996 by Resolution SU–40.
B. Ground Wires
Ground wires shall have a conductivity and
mechanical strength at least equal to that of No. 8 AWG medium–hard–drawn
copper wire; they shall not be installed on the top surfaces of crossarms;
and they shall have clearances of not less than 1.5 inches from hardware
in accordance with the provisions of Rules
52.7–B
and 52.7–C
.
Note: Revised October
9, 1996 by Resolution SU–40.
That
portion of the ground wires
attached on the face or back of wood crossarms or on the
surface of wood poles and structures shall be covered by a suitable protective covering (see Rule 22.8)
EXCEPTION: Ground wires of 0 - 750 volt circuits or equipment are not required to be covered where installed on crossarms supporting 0 - 750 volt conductors.
Minor separation, warping, and/or cracking of the protective covering is allowed, provided the ground wire is not exposed.
Ground wires of common neutral systems
are specially required to comply with the provisions of Rules
59.3–C
and 59.4
in addition to the provisions of this Rule 54.6–B
.
Ground wires installed on the
surface of service and meter poles (see
Rule 22.6–E
for definition) which terminate in effectively grounded meter or equipment
enclosures not more than eight feet above ground are not required to be covered
by a suitable protective covering (see Rule 22.8
for definition), provided they are encased in rigid steel conduit or No.
8 AWG minimum armored copper ground wire is used.
Note: Last
paragraph added July 26, 1966 by Decision No. 71009.
C. Lateral Conductors
(1) Lateral Runs: Lateral conductors installed as specified in this
Rule 54.6–C
are known as Lateral Runs.
(2) Conductors of 0 - 750 Volts: Lateral conductors of 0 - 750 volts
may be installed with less than the radial clearances between conductors,
specified in Table 2, Cases
16 and 17
, and with less than the clearance from the center line and surface of
pole, and from the surface of crossarm, as specified in
Table 1, Cases 8 and 9
, provided such conductors are suitably insulated and placed along the
bottom surface of crossarms. Such conductors when installed along the bottom
surface of crossarms and protected by plastic conduit having the properties
of the material specified in Rule 22.8–B
shall be considered to be suitably protected and allowed in the climbing
space.
Note: Revised February 13, 1980 by Resolution No. E–1863, May 22, 1990 by Resolution
No. SU–5 and January 19, 1994 by Resolution SU–25.
(3) Conductors of More than 750 Volts: Lateral conductors of more
than 750 volts may be installed with less than the radial clearances between
conductors, specified in Table
2, Cases 16 and 17
, and with less than the clearances from centerline and surface of pole,
and from the surface of crossarm, as specified in
Table 1, Cases 8 and 9
, provided such conductors are suitably insulated and are protected by
the plastic conduit specified in Rule 54.6–C2
, such conduit being placed along and attached to the bottom surface of
crossarm.
Note:
Revised January 19, 1994 by Resolution SU–25.
(4) Extent of Run: The suitable protective covering (see
Rule 22.8)
required for protection by this Rule 54.6–C
shall extend on the bottom surface of the crossarm and in no case shall
the covering be terminated at clearances from the centerline of pole less
than specified for conductors in
Table 1, Case 8
.
Note:
Revised November 21, 1990 by Resolution No. SU–6.
(5) Option: In Lieu of the foregoing lateral conductors may be installed
as specified in Rules 54.6–A
and 54.4–D9.
Note:
Revised May 1, 1961 by Resolution No. E–1088; June 7, 1965 by Decision
No. 69071 and January 6, 1968 by Decision No. 73455.
D. Vertical Runs
(1) Vertical Runs: Vertical conductors installed as specified in
this Rule 54.6–D
are known as Vertical Runs.
(2) Runs Less than 18 Inches from Pole Centerline: Vertical conductors
may be installed with less than the radial clearances between conductors,
specified in Table 2, Cases
16 and 17
, and on the surface of poles or less than 18 inches from centerline of
pole provided such conductors are suitably insulated and covered throughout
by a suitable protective covering (see Rule
22.8
for the definition of suitable protective covering). This protective covering
is not required over suitably insulated vertical conductors in metal conduit
attached to metal poles, towers, or other structures provided conduit and
structure are metallically connected and effectively grounded.
Note:
Revised January 19, 1994 by Resolution SU–25.
(3) Runs 18 Inches from Pole Centerline: Vertical conductors may
be installed with less than the radial clearances between conductors, specified
in Table 2, Cases 16 and 17
, and at a distance of more than 18 inches from the centerline of any pole
provided that such conductors are suitably insulated and covered by suitable
protective covering. Such conductors shall be located outside of the climbing
and working spaces and shall not pass between conductors of different ownership
except between the pole pair and at a clearance therefrom of no less than
6 inches.
Note:
Revised January 19, 1994 by Resolution SU–25.
(4) Option: In lieu of the foregoing, vertical conductors may be installed as unprotected conductors, specified in Rules 54.6–A and 54.4–D9 .
(5) Runs within 8 Feet of Ground: Vertical conductors installed as specified in Rule 54.6–D2 and 54.6–D3 , and which extend within 8 feet of the ground shall be treated as risers. Runs which terminate in the top of enclosures which afford ample mechanical protection to the runs may extend within 8 feet of the ground but not less than 6 feet of the ground without being treated as risers.
(6) Runs Encased in Grounded Metal Covering: Vertical conductors
where encased in grounded metal conduit, sheath, or shield, shall be treated
as risers.
Note:
Revised February 7, 1964 by Decision
No. 66707; June 7, 1965 by Decision No. 69071; January 6, 1968 by Decision
No. 73455 and July 22, 1968 by Decision No. 74342.
E. Risers
(1) Encased from Ground Level to 8 Feet above the Ground: Risers
from underground cables or other conductors shall be encased from the ground
level to a level not less than 8 feet above the ground (see Figure 54–4
A
& B
) in:
a) Securely or effectively grounded iron or steel pipe (or other covering at least of equal strength); or
b) Nonmetallic conduit, provided that risers of circuits in excess of 750 volts shall have an effectively grounded metallic shield. Such conduit shall be of material as specified in Rule 22.8–B ; or
c) Nonmetallic U–shaped moulding, provided that risers of circuits in excess of 750 volts shall have an effectively grounded metallic shield. Such U–shaped moulding shall be of a material as specified in Rule 22.8–B , and the U–shaped moulding shall be installed with a backup plate (to effectively encase the cable or conductors) of similar type material.
(2) Covered from 8 Feet above the Ground Level and above: All risers
from underground cables or other conductors which pass through an unrelated
conductor or cable level shall be covered or encased by material as described
in Rule 54.6–E1
or by a suitable protective covering as described in
Rule 22.8
from a distance of 8 feet above the ground to:
a) Not less than 18 inches above supply conductors.
b) Not less than 36 inches above communication conductors for supply risers of 750 volts or less; and
c) Not less than 48 inches above communication conductors for supply risers of 750 - 7500 volts; and
d) Not less than 60 inches above communication conductors for supply risers of more than 7500 volts.
When iron or steel pipe, or other material not meeting the minimum insulating
efficiency as specified in Rule
22.8–B
is used it shall be terminated or covered by suitable protective covering
where within a vertical distance of 8 feet from communication conductors
or cables, or unprotected supply conductors.
(3) Covering Joints: Where two sections of suitable protective covering
join together (at joints) they shall be covered to prevent exposing the
underground cables or other conductors by:
a) The extension of either or both such coverings; or
b) A coupling of equal material; or
c) A strap of equal material.
(4) Climbing Space: Protective coverings for risers, other than wood
meeting the requirements of Rule 22.8
, are not allowed in the climbing space.
(5) Clearance between Insulated Conductors: The radial clearances
between conductors, specified in
Table 2, Cases 16 and 17
, are not required between suitably insulated conductors or cables in the
same riser.
(6) Clearance from Centerline and Surface of Poles: Suitably insulated
riser conductors or cables can be installed with less than the centerline
and surface of pole clearances specified in
Table 1, Cases 8 and 9
respectively.
(7) Metal Poles, Towers and Other Metallic Structures: Protective
covering (suitable) is not required over risers encased in effectively grounded
nonclimbable metal poles or in iron or steel pipe attached to a steel pole,
steel tower or other metallic structure provided the iron or steel pipe is
effectively grounded and is metallically connected to such metal structure.
Note:
Revised February 7, 1964 by Decision No. 66707;
June 7, 1965 by Decision No. 69071 and September 12, 1973 by Decision No.
81872; February 13, 1980 by Resolution E–1863; March 9, 1988 by Resolution
E–3076 and January 19, 1994 by Resolution SU–25.
F. Termination of Risers and Runs Encased in Metal
Conduit
Where risers and runs are covered or encased with suitable protective
covering (Rule 22.8
) see Rule 54.6–G
.
Where risers and runs are encased in metal conduit or other materials
not meeting the minimum insulating efficiency as specified in
Rule 22.8–B
(suitable protective covering), e.g. lead risers encased in metal conduit,
and such metal conduit or other conducting material extends within 4 feet
of any supply conductor level the following rules shall apply.
(1) Terminals, Terminal Fittings, and Weather Heads: Grounded portions
of terminals, grounded terminal fittings, and grounded weather heads of
risers or runs shall not extend above the level of line conductors to which
their terminal leads are connected except:
a) Where the line conductors are installed in vertical configuration
in partial underground distribution; or
b) Where the line conductors are deadended on the same crossarms that
the grounded portions of the terminal, grounded terminal fitting, or grounded
weather head is attached and no line conductors supported on those crossarms
extend past the grounded portions of the terminals, terminal fitting, or
weather head, and no buck arm construction is involved; or
c) Where conductors in excess of 7,500 volts are installed in vertical
configuration on crossarms, and the grounded portions of terminals, grounded
terminal fittings, or grounded weather heads are mounted on the same crossarms
which support the conductors to which the terminal leads are connected.
(2) Climbing Space Obstructions: Terminals, terminal fittings, and
weather heads of risers or runs are not allowed in the climbing space.
(3) Clearance from Centerline of Pole: For clearance of energized
portions of terminals and their unprotected leads from centerline of pole,
see Table 1, Case 8
.
EXCEPTION:
In partial underground distribution (
Rule 22.5) energized portions of the terminals may be less than the clearances from
centerline of pole specified in
Table 1, Case 8, Column E
(15 or 18 inches) but shall not be less than 6 inches from the surface
of the nonclimbable metal pole and grounded metal surface associated therewith.
(4) Vertical and Radial Clearance from Conductor below: All exposed
grounded surfaces of terminals, terminal fittings, weather heads, cables
or conduit bends, or suitably insulated cable surfaces of risers and runs
shall be at least 18 inches vertically and 18 inches radially from the next
unprotected conductor level below. (See Figure 54–4
A
& B
).
(5) Protection from the Grounded Metal Conduit, Terminal Fitting, or
Weather Head at the Upper End of Vertical Runs or Risers on Wood Poles:
Any exposed grounded metal conduit, grounded terminal fitting, or grounded
weather head at the upper end of the vertical run or riser on wood poles
within distances from the centerline of pole less than as specified in
Table 1, Case 8, shall be protected by a wood crossarm or wood block placed above it at
a distance not exceeding 4 inches.
EXCEPTIONS: The wood block may be omitted if the exposed grounded
metal conduit, grounded terminal fitting, or grounded weather head at the
upper end of a vertical run or riser of 750 volts or less is:
a) On the same side of a pole as, and not more than one foot below a
transformer; or
b) Not more than 6 inches and not less than 3 inches below the lowest
conductor of a rack, and such conduit, fitting, or weather head is approximately
centered in the vertical plane under the rack.
(6) Exposed Suitably Insulated or Grounded Surfaces: Exposed suitably
insulated or grounded portions of cable, conduit bends, terminal fittings,
terminals, and weather heads, located at the upper end of vertical runs
or risers supported on climbable poles or structures should be arranged
with as little exposed surface as practicable. Such cable or conduit bends
are not required to be covered by a suitable protective covering (See
Figure 54–4
A
& B
) provided that no portion of their exposed surfaces are within the climbing
space.
(7) 0 - 750 Volt Terminal Fittings and Weather Heads: The grounded
terminal fittings, grounded weather heads, and unprotected cables or leads
to and from risers or runs of 0 - 750 volts installed on the surfaces of
poles shall not be or pass within the climbing space, but may have a clearance
of less than 15 inches from centerline of pole (
Table 1, Case 8
) and less than 3 inches from the surface of pole or crossarm (
Table 1, Case 9
). It is recommended that cables from such terminal fittings and weather
heads be suitably insulated and, where practicable, carried as protected
lateral runs on the bottom surface of crossarms (See Rule 54.6–C
).
(8) Vertical Clearances from Lead Wires and Drip Loops to Other Conductors:
The vertical clearances between the lowest point of lead wires (See
unprotected conductor Figure 54–4
A
& B
) of a riser or run (vertical or lateral) and the next conductor level
below shall conform to the requirements specified in
Rule 54.4–C6
. For the vertical clearances between supply drip loops and a communication
conductor level below see Rule 92.1–F3
.
Note:
Revised February 7, 1964 by Decision
No. 66707; March 29, 1966 by Decision No. 70489; July 26, 1966 by Decision
No. 71009; August 9, 1966 by Decision No. 71094; September 18, 1967 by Decision
No. 72984; May 22, 1990 by Resolution SU–5 and January 19, 1994 by Resolution
SU–25.
G. Termination of Risers and Runs Covered with Suitable
Protective Covering
For termination of risers and runs encased in metal conduit or other
materials not meeting the minimum insulating efficiency as specified in
Rule 22.8–B
(suitable protective covering) and which extend within 4 feet of any supply
conductor level see Rule 54.6–F
.
Where risers and runs are covered or encased with suitable protective
covering (Rule 22.8
) the following rules shall apply.
(1) Grounded Portions of Termination Apparatus (Terminals, Potheads,
Stress Cones, etc.): Grounded portions of the termination apparatus
of risers or runs shall not extend above the level of line conductors to
which their terminal leads are connected except:
a) where line conductors are deadended on the same crossarm or bracket
that the termination apparatus is attached, and no line conductors supported
on that crossarm or bracket extend past the grounded portion of the termination
apparatus, and no buck arm construction is involved; or
b) where line conductors are installed in vertical or triangular configuration
and the grounded portions of the termination apparatus are mounted on the
same crossarms, or other supports, which support the line conductors to
which the terminal leads are connected.
(2) Climbing Space Obstructions: Termination apparatus (terminals,
potheads, stress cones, etc.) of risers or runs are not allowed in the
climbing space.
(3) Clearance from Centerline of Pole: For clearance of energized
portions of terminals (see Figure 54–4
A
and B
) and their unprotected leads from centerline of pole, see
Table 1, Case 8
.
(4) Vertical and Radial Clearance from Conductors below: All exposed
grounded surfaces of termination apparatus (terminals, potheads, stress
cones, etc.), cables or conduit bends, or suitably insulated cable surfaces
of risers and runs, shall be at least 18 inches vertically and 18 inches
radially from the next unprotected conductor level below (see Figure
54–4 A
and B
).
(5) Exposed Suitably Insulated or Grounded Cable: Exposed suitably
insulated or grounded portions of cable located at the upper end of vertical
runs or risers (see Figure 54–4
A
and B
) supported on climbable poles or structures are not required to be covered
by a suitable protective covering provided that no portion of their exposed
surfaces are within the climbing space.
(6) Vertical Clearance from Lead Wires and Drip Loops to Other Conductors:
The vertical clearances between the lowest point of lead wires (see
unprotected conductor Figure 54–4
A
and B
) of a riser or run (vertical or lateral) and the next conductor level
below shall conform to the requirements specified in
Rule 54.4–C6
. For the vertical clearances between supply drip loops and a communication
conductor level below see Rule 92.1–F3
.
The suitably insulated cables at the upper end of vertical runs and risers
can be installed with less than the radial clearances between conductors
specified in Table 2, Cases
16 and 17
, and with less than the centerline and surface of pole clearances specified
in Table 1, Cases 8 and 9
respectively.
Note:
Added January 19, 1994 by Resolution SU–25.
H. Clearances from Hardware on Wood Poles or Wood Structures
On wood poles or wood structures, all ground wires, conductor or cable
sheaths (concentric wire, metallic braids and tapes, or other metallic
coverings), metallic conduits of risers or runs and the metallic hardware
used for attaching such conduits, and metallic hardware used for attaching
wood and U–shaped plastic ground moulding (excluding plastic conduit) to
wood poles or wood structures shall have a clearance of not less than 1.5
inches from guy hardware, bolts, braces, pole steps, and other metallic
hardware not associated with the risers or runs. In cases where it is not
practicable to obtain at least 1.5 inches of air–gap and creepage distance,
suitable insulating material (sheeting, conduit, etc.) meeting the minimum
insulating efficiency, as required by Rule
22.8–B
, of 1100 kV/in (1.1 kV/mil) shall be used to provide the necessary creepage
distance of 1.5 inches.
Note:
Revised February 7, 1964 by Decision No. 66707; March 29, 1966 by Decision
No. 70489; July 26, 1966 by Decision No. 71009; August 9, 1966 by Decision
No. 71094; September 18, 1967 by Decision No. 72984; May 22, 1990 by Resolution
SU–5 and Renumbered January 19, 1994 by Resolution SU–25.
I. Attachment of Protective Covering
Protective covering shall be attached to poles, structures, crossarms,
and other supports by means of corrosion–resistant materials (straps, plumbers
tape, lags, nails, staples, screws, bolts, etc.) which are adequate to
maintain such covering in a fixed position.
Where such covering consists of wood moulding, rigid plastic moulding,
or other suitable protective moulding, the distance between the attachment
materials (straps, plumbers tape, lags, nails, staples, screws, bolts,
etc.) shall not exceed 36 inches on either side of the moulding.
When moulding is utilized that is subject to expansion due to temperature variation, a gap shall be provided between each section (at joints). All gaps between sections shall be covered by material equal to the moulding being utilized to prevent contact with conductors or cables covered by such moulding.
When building wood box moulding, to prevent damage to the covered cable
or conductor, due care shall be exercised to avoid the possibility of nails
protruding through any inner surface of such covering.
Note: Revised January 6, 1968 by Decision
No. 73455 and January 19, 1994 by Resolution SU–25.