Standard Specifications for Road, Bridge, and Municipal Construction 2020 (M 41-10)

Page 8-110

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duct and innerduct shall be sealed with rodent and moisture resistant foam designed for
this application and installed per manufacturer’s recommendations.

8-20.3(5)B1

Rigid Metal Conduit

Slip joints or running threads will not be permitted for coupling metallic conduit; however,
running threads will be permitted in traffic signal head spiders and rigid metal conduit
(RMC) outer-duct. When installing rigid metal conduit (RMC), if a standard coupling
cannot be used, an approved three-piece coupling shall be used. Conduit bodies, fittings
and couplings for rigid metal conduit (RMC) shall be cleaned first and then painted with
one coat of paint conforming to

Section 9-08.1(2)B

. The paint shall have a minimum wet

film thickness of 3-mils. The painted coating shall cover the entire coupling or fitting. The
threads on all metal conduit shall be rust-free, clean, and painted with colloidal copper
suspended in a petroleum vehicle before couplings are made. All metallic couplings shall
be tightened so that a good electrical connection will be made throughout the entire
length of the conduit run. If the conduit has been moved after assembly, it shall be given a
final tightening from the ends prior to backfilling.

Rigid metal conduit (RMC) ends shall be terminated with grounded end bushings. Rigid
metal conduit (RMC) entering cable vaults or pull boxes shall extend 2-inches beyond the
inside wall face (for the installation of grounded end bushing and bonding).

Rigid metal conduit (RMC) entering concrete shall be wrapped in 2-inch-wide pipe wrap
tape with a minimum 1-inch overlap for 12-inches on each side of the concrete face. Pipe
wrap tape shall be installed per the manufacturer’s recommendations.

Rigid metal conduit (RMC) bends shall have a radius consistent with the requirements of
Code Article 344.24 and other articles of the Code. Where factory bends are not used,
conduit shall be bent, using an approved conduit bending tool employing correctly sized
dies, without crimping or flattening, using the longest radius practicable.

Where the coating on galvanized conduit has been damaged in handling or installing, such
damaged areas shall be thoroughly painted with paint conforming to

Section 9-08.1(2)B

Metal conduit ends shall be threaded and protected with a snug fitting plastic cap that
covers the threads until wiring is started.

8-20.3(5)B2

Non-Metallic Conduit

Where non-metallic conduit is installed, care shall be used in excavating, installing, and
backfilling, so that no rocks, wood, or other foreign material will be left in a position to
cause possible damage.

PVC conduit ends shall be terminated with end bell bushings. PVC or HDPE conduit
entering cable vaults and pull boxes shall terminate with the end bell flush with the inside
walls of the Structure.

Non-metallic conduit bends, where allowed, shall conform to Article 352.24 of the Code.
Eighteen-inch radius elbows shall be used for PVC conduit of 2-inch nominal diameter
or less. Standard sweep elbows shall be used for PVC conduit with greater than 2-inch

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nominal diameter unless otherwise specified in the Plans. In nonmetallic conduit less than
2-inch nominal diameter, pull ropes or flat tapes for wire installation shall be not less than
¼-inch diameter or width. In nonmetallic conduit of 2-inch nominal diameter or larger, pull
ropes or flat tapes for wire installation shall be not less than ½-inch diameter or width.
When HDPE conduit is used for directional boring, it shall be continuous, with no joints,
for the full length of the bore. The conduit run shall be extended to the associated outlets
with the same schedule HDPE or PVC conduit. Entry into associated junction box outlets
shall be with the same schedule PVC conduit and elbows. The same requirements apply
for extension of an existing HDPE conduit crossing.

PVC conduit and elbows shall be connected to HDPE conduit with an approved
mechanical coupling. The connection shall have minimum pullout strength of 700-pounds.
Prior to installation of a mechanical coupling, the HDPE conduit shall first be prepared
with a clean, straight edge. A water-based pulling lubricant may be applied to the
threaded end of the mechanical coupling before installation. Solvent cement or epoxy
shall not be used on the threaded joint when connecting the HDPE conduit to the
mechanical coupling. The mechanical coupling shall be rotated until the HDPE conduit
seats approximately ¾ of the distance into the threaded coupling depth.

For PVC installation through a directional bore, the PVC shall be in rigid sections
assembled to form a watertight bell and spigot-type mechanical joint with a solid retaining
ring around the entire circumference of the conduit installed per the manufacturer’s
recommendations. The conduit run shall be extended beyond the length of the bore,
to the associated outlets with the same mechanical coupled PVC or with standard PVC
conduit of the same schedule. The same requirements apply for extension of an existing
PVC conduit Roadway crossing.

PVC conduit shall be assembled using the solvent cement specified in

Section 9-29.1

Conduit ends shall be protected with a snug fitting plastic cap until wiring is started.

Conduit caps, end bells and the section of PVC between the coupling and end bell
bushing in cabinet foundations shall be installed without glue.

8-20.3(5)C

Conduit Size

The size of conduit used shall be as shown in the Plans. Conduits smaller than 1-inch
electrical trade size shall not be used unless otherwise specified, except that grounding
conductors at service points may be enclosed in ½-inch-diameter conduit.

Conduit between light standards, PPB, PS, or Type 1 poles and the nearest junction box
shall be the diameter specified in the Plans. Larger size conduit is not allowed at these
locations. At other locations it shall be the option of the Contractor, at no expense to the
Contracting Agency, to use larger size conduit if desired, provided that junction box or
vault capacity is not exceeded. Where larger size conduit is used, it shall be for the entire
length of the run from outlet to outlet.

Conduit runs with innerduct, shall have 4-inch outer-duct and shall be installed with four
1-inch innerduct unless otherwise indicated in the Plans.

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8-20.3(5)D

Conduit Placement

Conduit shall be laid so that the top of the conduit is a minimum depth of:
1.  24-inches below the bottom of curb in the sidewalk area.
2.  24-inches below the top of the untreated surfacing on a Roadbed.
3.  48-inches below the bottom of ties under railroad tracks unless otherwise specified

by the railroad company.

4. 36-inches below finish grade when installed using conduit plowing method.
5. 24-inches below the finish grade in all other areas.

Conduit entering through the bottom of a junction box shall be located near the end
walls to leave the major portion of the box clear. At all outlets, conduit shall enter from
the direction of the run, terminating 6 to 8-inches below the junction box lid and within
3-inches of the box wall nearest its entry location.

Conduit runs shown in the Plans are for Bidding purposes only and may be relocated with
approval of the Engineer, to avoid obstructions.

8-20.3(5)D1 Surface Mounting

Where surface mounting of conduit is required, supports shall consist of channel with
clamps sized for the conduit. Support spacing shall comply with the Code, with the
exception that spacing of channel supports for conduit shall not exceed 5-feet.

The minimum distance between adjacent clamps and between the clamp and the end of
the channel supports shall be 1-inch. Channel supports shall be installed with stops, to
prevent clamps from sliding out of the ends.

8-20.3(5)D2 Structures

All conduits attached to or routed within bridges, retaining walls, and other structures
shall be equipped with approved expansion, deflection, and/or combination expansion/
deflection fittings at all expansion joints and at all other joints where structure movement
is anticipated, including locations where the Contractor, due to construction method,
installs expansion and/or construction joints with movement. All conduit fittings shall
have movement capacity appropriate for the anticipated movement of the Structure at
the joint. Approved deflection fittings shall also be installed at the joint between the
bridge end and the retaining wall end, and the transition from bridge, wall, or other
structure to the underground section of conduit pipe.

8-20.3(5)E

Method of Conduit Installation

Conduit shall be placed under existing pavement by approved directional boring, jacking,
or drilling methods at locations approved by the Engineer. The pavement shall not be
disturbed unless allowed in the Plans or with the approval of the Engineer in the event
obstructions or impenetrable soils are encountered. High density polyethylene (HDPE)
conduit runs, which enter the traveled way or shoulders, shall be installed using the
directional boring method.

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8-20.3(5)E1

Open Trenching

When open trenching is allowed, trench construction shall conform to the following:
1. The pavement shall be saw-cut a minimum of 3-inches deep. The cuts shall be

parallel to each other and extend 2-feet beyond the edge of the trench.

2. Pavement shall be removed in an approved manner.
3. Trench depth shall provide a minimum cover for conduit of 24-inches below the top

of the roadway base.

4. Trench width shall be 8-inches or the conduit diameter plus 2-inches, whichever

is larger.

5. Trenches located within paved Roadway areas shall be backfilled with Controlled

density fill (CDF) meeting the requirements of

Section 2-09.3(1)E

. The controlled

density fill shall be placed level to, and at the bottom of, the existing pavement. The
pavement shall be replaced with paving material that matches the existing pavement.

6. On new construction, conduit shall be placed prior to placement of base course

pavement.

8-20.3(5)E2

Conduit Plowing

All conduit plowing shall be supervised by a licensed electrical Contractor.

The starting point shall be anchored or held such that conduit movement at the start of
the plowing operation is kept to a minimum. The conduit reel shall be mounted on the
vehicle such that conduit movement is kept to a minimum once it is in the ground. Use
of a stationary reel is not allowed. The feed shoe shall have rollers which conform to the
conduit at a radius of not less than 15 times the diameter of the conduit. The conduit will
not be permitted to pass over stationary guides nor over rollers or sheaves, which will
permit a bend radius of less than 15 times conduit diameter. The width of the tooth and
feed shoe shall not exceed the conduit diameter by more than two-inches.

The conduit shall be installed using a continuous reel, with no joints, for the full length
of the conduit run, unless conduit splicing is allowed as indicated below.

If an obstruction is encountered that cannot be plowed through, the following remedies
shall be attempted in order:
1. Contractor shall stop the plowing operation and attempt to remove the obstruction.

If the obstruction is removed, plowing operations shall continue along the
approved path.

2. Deviations of up to one foot from the projected path may be authorized by the

Engineer, provided the new route does not result in total conduit run bends
exceeding NEC requirements. Deviations in excess of one foot from the projected
path are not allowed and the maximum taper rate is 1-inch per linear foot of conduit.

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3. The Contractor may request approval to intercept the installed conduit and route

another section of HDPE to avoid the obstruction, provided the new route does not
result in total conduit run bends exceeding NEC requirements. Connection between
the sections shall be accomplished using an approved fusion splicing method, which
is compatible with the conduit manufacturer’s recommendations.

4. Where none of the above remedies are successful, all conduit installed so far in that

run shall be removed and a new plow path established to avoid the obstruction.

In the event of a breakage, all conduit installed in that run shall be removed.

The conduit run shall be extended to the associated outlets, subject to the same
requirements indicated when HDPE is installed using the directional boring method.

The depth of installation shall be continually adjusted as necessary to compensate for
changes in terrain.

Plowed conduit shall be laid so that the top of the conduit is a minimum depth of
36-inches below the finish grade with the exception that the conduit shall be swept up to
enter the knock outs of associated pull boxes or cable vaults.

The plow placing the conduit shall be marked at a proper distance above the plow’s
conduit exit point to indicate when the minimum installation depth is not met. The mark
shall be visible from a safe distance from the plowing operation when it is exposed
above ground. While plowing this mark must remain below ground level at all times, with
the exception of the entry and exit points at the end of the run, in order to ensure that
minimum burial depth of the conduit is achieved.

If the depth mark on the plow comes above ground, the Contractor shall stop the
plowing operation and attempt to correct the placement depth. If the conduit depth
can be verified to meet the minimum burial requirements at the location where the
depth mark came above ground, the plowing operation shall resume subject to the
Engineers approval.

The compacted surface shall be firm, non-yielding, and result in a finished surface that
matches the lines and grades of the terrain prior to plowing.

8-20.3(5)E3 Boring

Bore pits shall be backfilled and compacted in accordance with

Section 2-09.3(1)E

Directional boring, jacking or drilling pits shall be a minimum of 2-feet from the edge of
any type of pavement, unless otherwise approved by the Engineer. Excessive use of water
that might undermine the pavement or soften the Subgrade will not be permitted.

When approved by the Engineer, small test holes may be cut in the pavement to locate
obstructions. When the Contractor encounters obstructions or is unable to install conduit
because of soil conditions, as determined by the Engineer, additional Work to place the
conduit will be paid in accordance with

Section 1-04.4

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8-20.3(5)E4

Directional Boring

Directional boring for electrical installations shall be supervised by a licensed electrical
contractor in accordance with

Section 8-20.1(1)

. Where directional boring is called for,

conduit shall be installed using a surface-launched, steerable drilling tool. Drilling shall
be accomplished using a high-pressure fluid jet tool-head. The drilling fluid shall be used
to maintain the stability of the tunnel, reduce drag on the conduit, and provide backfill
between the conduit and tunnel. A guidance system that measures the depth, lateral
position, and roll shall be used to guide the tool-head when creating the pilot hole. Once
the pilot hole is established, a reamer and swivel shall be used to install the conduit.
Reaming diameter shall not exceed 1.5 times the diameter of the conduits being installed.
Conduit that is being pulled into the boring shall be installed in such a manner that the
conduit is not damaged during installation. The pullback force on the conduit shall be
controlled to prevent damage to the conduit. A vacuum spoils extraction system shall be
used to remove any excess spoils generated during the installation. Excess drilling fluid
and spoils shall be disposed of. The method and location used for disposal of excess
drilling fluid and spoils shall be subject to the Engineer’s approval. Drilling fluid returns
(caused by fracturing of formations) at locations other than the entry and exit points
shall be minimized. Any drilling fluid that surfaces through fracturing shall be cleaned up
immediately. Mobile spoils-removal equipment capable of quickly removing spoils from
entry or exit pits and areas with returns caused by fracturing shall be used as necessary
during drilling operations.

8-20.3(5)E5

Boring with Casing

Where boring with casing is called for, the casing shall be placed using an auger inside the
casing to remove the soil as the casing is jacked forward. The auger head shall proceed no
more than 4-inches ahead of the pipe being jacked. Boring operations shall be conducted
to prevent caving ahead of the pipe. Installed casing pipe shall be free from grease, dirt,
rust, moisture, and any other deleterious contaminants.

The space between the conduit and casing shall be plugged with sandbags and a
grout seal 12-inches thick at each end of the casing. Casing abandoned due to an
encountered obstruction shall be grout sealed in the same manner. Grout shall conform
to

Section 9-20.3(4)

In lieu of sandbags and grout, unopened prepackaged concrete and grout may be used
to seal the casing.

Material shall not be removed from the boring pit by washing or sluicing.

All joints shall be welded by a Washington State certified welder. Welding shall conform
to AWS D 1.1-80 Structural Welding Code, Section 3, Workmanship.

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8-20.3(6) Junction Boxes, Cable Vaults, and Pull boxes

Standard Duty and Heavy-Duty junction boxes, pull boxes, and cable vaults shall be
installed at the locations shown in the Plans. The Contractor may install, at no expense to
the Contracting Agency, such additional boxes as may be desired to facilitate the Work.
Junction box installation shall conform to details in the

Standard Plans

Cable vaults and pull boxes shall be installed in accordance with the following:
1. Excavation shall be performed in accordance with

Section 2-09

2. Cable vaults and pull boxes shall be installed on 6-inches of crushed surfacing, in

accordance with

Section 9-03.9(3)

, placed on a compacted or undisturbed level

foundation.

3. All openings around conduits shall be sealed and filled with grout in accordance with

to prevent water and debris from entering the

vaults or pull boxes.

4.  Backfilling around the Work shall not be allowed until the concrete or mortar has set.
5.  Pull boxes shall be installed in accordance with Plans and details.
6.  Pull boxes shall be configured such that the tensile and bending limitations of the

fiber optic and other cables are not compromised. Pull boxes shall be configured to
mechanically protect the fiber optic and other cables against installation force as well
as inert forces after cable pulling operations.

7. Upon acceptance of Work, cable vaults, and pull boxes shall be free of debris

and ready for cable installation. All grounding requirements shall be met prior to
cable installation.

8. Where installed near steel casings, the pull boxes and cable vaults shall be offset

3 feet, minimum, from the centerline of the casing. Factory bends shall be used to
route the conduits to the cable vault or pull box.

Adjustments involving raising or lowering the junction boxes shall require conduit
modification if the resultant clearance between the top of the conduit and the junction
box lid becomes less than 6 inches or more than 10 inches in accordance with the Plans.

Cable vaults and pull boxes shall be adjusted to final grade using risers or rings
manufactured by the cable vault and pull box manufacturer. Cable vaults and pull boxes
with traffic bearing lids shall be raised to final grade using ring risers to raise the cover
only. All voids resulting from the adjustment shall be backfilled with materials matching
adjacent surfacing material and compacted in accordance with

Section 2-09.3(1)E

Damage to the junction boxes, pull boxes, cable vaults and the associated conduit system,
or wiring resulting from the Contractor’s operations, shall be repaired to the Engineer’s
satisfaction at no additional cost to the Contracting Agency.

Both existing and new junction boxes, pull boxes, and cable vaults shall be adjusted to
be flush with the finished grade as well as with the grade during the various construction
stages proposed in the Contract.

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Where conduit and junction boxes are placed in barrier, the Contractor shall coordinate
the Work of the Contractor constructing the barrier and the electrical Contractor so that
each junction box placed in the barrier is placed in correct alignment with respect to the
barrier, with the face of the box flush or uniformly chamfered within ⅛ inch of the barrier
surface. If any point on the surface of the junction box placed in barrier is recessed more
than ⅛ inch from the surface of the barrier, the Contractor shall install a box extension
meeting the Engineer’s approval and grout around the extension or remove and replace
the entire section of barrier.

Standard Duty pull boxes, cable vaults, and concrete junction boxes installed in sidewalks,
walkways, and shared-use paths shall have slip-resistant surfaces, be flush with the
surface, and match the grade of the sidewalk, walkway, and shared-use path. The boxes,
vaults, and junction boxes shall not be placed in curb ramps, curb ramp landings, or the
gutter areas associated with the curb ramps. Standard Duty nonconcrete junction boxes
shall not be installed in sidewalks, walkways, or shared-use paths.

8-20.3(7) Messenger Cable, Fittings

Messenger cable shall be secured to steel strain poles by means of pole bands, and to
timber poles by means of single strand guy eye bolts. Pole bands and eyebolts shall be
installed as detailed in the Plans.

Messenger cable shall be secured to eye bolts or strain clamps at poles by the use of
approved self-locking cable clamp type dead-ending devices. Messenger cable shall be
secured to bull rings and anchors by two approved U-bolt connectors and guy thimbles.

Traffic signal control cable shall be secured to the messenger cable by cable ties. The
ties shall be black nylon with ultraviolet protection and rated at 120-pound minimum
unlocking strength.

Down guy assemblies shall be installed as detailed in the

Standard Plans

8-20.3(8) Wiring

All underground wiring shall be installed in conduit unless specifically noted otherwise
in the Contract. All wiring in conduit shall be installed with a lubricant recommended by
cable/conductor manufacturer.

With the exception of induction loop circuits, magnetometer circuits and illumination
circuits, all wiring shall run continuously, without splices, from a terminal located in a
cabinet, compartment, pedestrian push button assembly, or signal head to a similarly
located terminal. Illumination circuit terminals and traffic circuit signal terminals located
below grade will not be allowed. Video detection systems cable installation shall follow
manufacturer’s Specification, except no below grade terminals will be allowed.

All splices in underground illumination circuits, induction loops circuits, and
magnetometer circuits shall be installed in junction boxes. The only splice allowed in
induction loop circuits and magnetometer circuits shall be the splice connecting the
induction loop lead in conductors or magnetometer lead in conductors to the shielded

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lead in cable. Splices for induction loop circuits and magnetometer circuits shall be:
heat shrink type with moisture blocking, material sized for conductors, epoxy filled clear
rigid mold splice kits or rigid re-enterable type splice kits. Conductors for rigid mold kits
shall be centered in the splice mold prior to installation of the encapsulation material.
Magnetometer and induction loop splices shall be soldered. All connections with #10 and
smaller wire shall use copper crimped connectors installed with a positive action (ratchet)
tool, except where setscrew connections are allowed for quick disconnects as described
in

Section 9-29.7

. The non-insulated die shall be an indent type and insulated die shall be

of a smooth shape capable of crimping pre-insulated terminals and connectors. The tool
shall be compound lever type with a ratchet mechanism to ensure positive closure for
full crimping cycle. The tool shall be field adjustable to proper calibration with common
tools and materials. All connectors installed in splices shall be wrapped with two layers of
electrical tape. All epoxy splice kits shall be physically separated from other splices and
wiring within the junction box to avoid damage from heat during the casting process.

All termination for traffic signal control systems shall follow the conductor sequence color
code as shown in the following table.

Conductor Number

Color Code

Color Trace

Use

Red

Red or Don’t Walk

Orange

Yellow or Spare

Green

Green or Walk

White

Neutral

Black

Ped Call or Spare

White/Black

Neutral or Spare

Blue

Ped Call or Spare

Red/Black

Red or Don’t Walk

Orange/Black

Yellow or Spare

Green/Black

Green or Walk

Splices and taps on underground circuits shall be made with solderless crimp connectors
meeting the requirements of

Section 9-29.12

Only one conductor or one multiconductor cable per wire entrance will be allowed in any
rigid mold splice.

Aerial illumination splices shall employ vice or crimp type pressure connectors. Splice
insulation may be epoxy, heat shrink, or tape. Tape splice insulation, where allowed, shall
consist of thermoplastic electrical insulating tape equivalent to the original wire insulation
rating. It shall be well lapped over the original insulation, and there shall be a coating of
moisture resistant varnish applied and allowed to dry. Two layers of friction tape will then
be applied, and the splice shall be finished with a second complete coating of moisture
resistant varnish.

Quick disconnect connectors shall be installed in the base of all poles supporting a
luminaire. Every conductor above ground potential shall be served by a fused quick

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disconnect kit. Every conductor at ground potential shall be served by an unfused quick
disconnect kit.

Pole and bracket cable meeting the requirements of

Section 9-29.3(2)D

shall be installed

between the quick disconnects and the luminaire and between the sign light hand hole
and the isolation switch. In addition, the conductors from the isolation switch and the
sign light shall be minimum AWG 14, meeting the requirements of

Section 9-29.3(2)A

9-29.3(2)B

. Pole and bracket cable jacket shall be removed from the quick disconnect to

within 2 inches below the support bracket clamp.

Sufficient slack wire shall be installed at each junction box to allow any conductor, cable,
or splice within the junction box to be raised a minimum of 18 inches outside of the box.

Insulated neutral conductors shall be identified in accordance with the NEC requirements.
Every conductor at every wire termination, connector, or device shall have an approved
wire marking sleeve bearing as its legend, the circuit number indicated in the Contract. All
terminal strips shall also bear the circuit number consistent with the Contract.

At all illumination circuit splices, each wire entering the splice shall have an approved wire
marking sleeve bearing as its legend the circuit number indicated in the Contract.

All wiring, exclusive of the previously mentioned illumination circuits, at junction boxes
and at the controller cabinet shall have an approved tag with legends as follows:
1. Individual conductors – the circuit number indicated in the Contract.
2. Multiconductor cable – the numbers of the signal heads and/or pedestrian push

buttons served.

3.  Loop lead-in cable – the numbers of the loops served.
4.  Magnetometer cable – the numbers of the magnetometers served.
5.  Video detection camera lead-in cable – the numbers of the phases the

camera served.

6. ITS cameras – the number of the camera indicated in the Contract and the number

of the associated cabinet as indicated in the Plans.

7. Communication cable – labeled as Comm.

Drip loops shall be provided on all aerial conductors where they enter poles, signal heads,
or weather heads.

When conductors, either cable or single, are being installed, the Contractor shall not
exceed the tension limitations recommended by the manufacturer. Conductors may
be pulled directly by hand or with mechanical assistance. If conductors are pulled by
any mechanical means, a dynamometer with drop-needle hand shall be used on every
mechanically assisted pull.

On mechanically assisted pulls, insulation shall be stripped off the individual conductor
and the conductor formed into a pulling eye and firmly attached to the pulling rope/tape,
or a cable grip shall be used. The Contractor shall determine the maximum allowable

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pulling tension, taking into account the direction of the pull, type of raceway, cable
geometry, weight of the cable, the coefficient of friction, and side wall pressure, using the
information from the cable manufacturer. If there are bends in the raceway or sheaves
are used for the cable pull, the contractor shall use the cable manufacture’s side wall
pressure limits to determine the maximum pulling tension. The maximum pulling force
applied directly to the conductor when pulling eyes are used or when the conductor
is formed into a loop, shall be limited to that shown in the following table for copper
conductor. When a cable grip is applied over nonmetallic sheathed cables, the maximum
pulling force shall be limited to 1,000 pounds provided this is not in excess of the force as
determined above.

Conductor

Pounds

132

210

334

421

531

669

1/0

845

2/0

1,065

3/0

1,342

4/0

1,693

250 Kcmil

2,000

500 Kcmil

4,000

Adequate lubrication of the proper type to reduce friction in conduit and duct pulls shall
be utilized. The grease and oil-type lubricants used on lead sheathed cables shall not be
used on nonmetallic sheathed cables. Pulling tape shall meet the requirements of

Section

9-29.1(10)

. Pull string may not be used.

When wiring is noted for future connection, the ends of each wire or cable shall be sealed
with an approved heat shrink end cap.

If loop lead splices are not installed immediately after the installation of the loop leads
into the adjacent junction box, the ends of the two conductor “home run” cable shall be
sealed with heat shrink end caps to prevent entry of moisture into the two conductor
cable. All coaxial cables shall have heat shrink end caps installed prior to aerial or
underground installation of the cables to prevent moisture entry into the cable.

Multiconductor cable for signal displays shall be installed entirely through the mounting
fitting to a point a minimum of 1 inch inside the signal display housing before the
outer insulation is stripped back for the connection of individual conductors to the
terminal block.

Installation of coaxial or coaxial/Siamese cable or data cables with a 600 VAC rating will
be allowed in the same raceway with 480 VAC illumination cable.

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8-20.3(9) Bonding, Grounding

All metallic appurtenances containing electrical conductors (luminaires, light standards,
cabinets, metallic conduit, etc.) shall be made mechanically and electrically secure to form
continuous systems that shall be effectively grounded.

Install an equipment grounding conductor in all new conduit, whether or not the
equipment grounding conductor is called for in the wire schedule.

For each new conduit with innerduct install an equipment grounding conductor in only
one of the innerducts unless otherwise required by the NEC or the plans.

Bonding jumpers and equipment grounding conductors meeting the requirements of

Section 9-29.3(2)A3

shall be minimum #8 AWG, installed in accordance with the NEC.

Where existing conduits are used for the installation of new circuits, an equipment
grounding conductor shall be installed unless an existing equipment ground conductor,
which is appropriate for the largest circuit, is already present in the existing raceway. The
equipment ground conductor between the isolation switch and the sign lighter fixtures
shall be minimum #14 AWG stranded copper conductor. Where parallel circuits are
enclosed in a common conduit, the equipment-grounding conductor shall be sized by the
largest overcurrent device serving any circuit contained within the conduit.

Junction boxes with metallic lids shall have one 4-foot long tinned braided copper
equipment bonding strap with full circle connector lugs installed from each metallic
junction box lid(s) to the junction box frame. A non-insulated stranded copper conductor,
minimum #8 AWG, with a full circle crimp on connector (crimped with a manufacturer
recommended crimper) shall be connected to the junction box frame or frame bonding
stud, the other end shall be crimped to the equipment bonding conductor, using a “C”
type crimp connector. The equipment ground conductor shall not be cut or spliced except
at junction boxes.

Supplemental grounding shall be provided at light standards, signal standards, cantilever
and sign bridge Structures. Steel sign posts which support signs with sign lighting or
flashing beacons shall also have supplemental grounding. The supplemental ground
conductor shall be connected to the foundation rebar (all rebar crossings shall be wire
tied) by means of a grounding connector listed for use in concrete, and lead up directly
adjacent to a conduit installed within the foundation. The free end of the conductor
shall be terminated to the ground terminal, with an approved clamp, within the pole. If
no ground terminal is provided, bond to standard or post. Three-feet of slack shall be
provided inside the standard. Where a concrete and rebar foundation is not used the
supplemental ground shall be a grounding electrode placed in the hole next to the post
prior to back fill. For light standards, signal standards, cantilever and sign bridge Structures
the supplemental grounding conductor shall be #4 AWG non-insulated stranded copper
conductor. For steel sign posts which support signs with sign lighting or flashing beacons
the supplemental grounding conductor shall be #6 AWG non-insulated stranded
copper conductor.

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All connectors between bonding jumpers and equipment grounding conductors shall
be installed in accordance with the NEC. Identification of the equipment grounding
conductor shall conform to all code requirements.

Bonding of the equipment grounding system and neutral at the service point shall be
accomplished as required under the NEC. Grounding of the neutral shall be accomplished
only at the service or at a separately derived system.

Install a two grounding electrode system at each service entrance point, at each electrical
service installation and at each separately derived power source. The service entrance
grounding electrode system shall conform to the “Service Ground” detail in the

Standard

Plans

. If soil conditions make vertical grounding electrode installation impossible an

alternate installation procedure as described in the NEC may be used. Maintain a
minimum of 6 feet of separation between any two grounding electrodes within the
grounding system. Grounding electrodes shall be bonded copper, ferrous core materials
and shall be solid rods not less than 10 feet in length if they are ½ inch in diameter or not
less than 8 feet in length if they are ⅝ inch or larger in diameter.

The connection of the grounding electrode conductor to the grounding electrode shall be
made with two approved ground clamps.

Messenger cable shall be bonded to steel strain poles by means of a bond strap
connected between an approved U-bolt connector and a bonding lug on the pole.

At points where shields or shielded conductors are grounded, the shields shall be neatly
wired and terminated on grounding terminal strip.

8-20.3(10) Service, Transformer, and Intelligent Transportation System (ITS) Cabinets

Power sources shown in the Plans are approximate only; exact location will be determined
in the field.

Aerial fed transformer cabinets and type A, type B, or type C service cabinets shall include
a timber pole, as specified in

Section 9-29.6(3)

, a meter base, installed in accordance with

serving utility requirements, a 2- or 3-wire service breaker of size noted in the Plans, the
necessary conduit risers and ground assembly as noted in the

Standard Plans

. The timber

pole shall be set at a depth of 10 percent of the total pole length plus 2 feet. Modified
type B, type D and type E services shall be installed per Contract Plan, and service
description in

Standard Plans

. Pad mounted transformer cabinets shall be installed per

Contract Plans.

The service breaker shall be a standard thermal circuit breaker encased in a raintight
housing that can be padlocked.

Upon request of the Contractor, the Engineer will make the necessary arrangements
with the serving utility to complete the service connections. Electrical energy used prior
to Completion of the Contract will be charged to the Contractor, except that the cost of
energy used for public benefit, when the Engineer orders such operation, will be borne by
the Contracting Agency.

Illumination, Traffic Signal Systems, Intelligent Transportation Systems, and Electrical

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The service, transformer and ITS cabinets shall be marked with the service agreement
letters and numbers as noted in the Plans. The markings shall be installed on the outside
cabinet door near the top of the cabinet. The markings shall be series C using stencils and
black enamel alkyd gloss paint conforming to Federal Specification TT-E-489F.

8-20.3(11) Testing

The Contractor shall conduct the following tests on all electrical circuits with nominal
operating voltage between 115-volts and 600-volts, in the presence of the Engineer:
1. Test the continuity of each circuit.
2. Test for grounds in each circuit, which shall consist of the physical examination of the

installation to ensure that all required ground jumpers, devices, and appurtenances
do exist and are mechanically firm.

3. Using a megohm meter, a 500-volt test on each new circuit between the conductor

and ground with all switch boards, panel boards, fuse holders, switches, receptacles,
and overcurrent devices in place. All readings shall be recorded. The Contractor
shall furnish the Engineer with three copies of the test results identifying observed
readings with their respective circuits.

The insulation resistance shall not be less than 50 megohms between the conductor
and ground on new circuits with a total single conductor length of 2,500 feet and
over, nor less than 50 megohms on new circuits with single conductor length of less
than 2,500 feet.

Any change in the above stated minimum readings must be approved in writing
by the Engineer. Only those factors based on dialectric properties of conductor
insulations, splicing insulations, terminal strip castings, etc., will be cause for
consideration of a variance.

4. A functional test in which it is demonstrated that each and every part of the system

functions as specified.

For those new circuits below 115-volts nominal, except induction loop circuits and test
direct burial circuits, the circuits shall be tested with a 500-volt megger for continuity,
ground, and a test to demonstrate the circuit functions as specified. The megger test shall
show an insulation resistance of not less than 8-megohms to ground.

Any fault in any material or in any part of the installation revealed by these tests shall be
replaced or repaired by the Contractor in a manner approved by the Engineer, and the
same test shall be repeated until no fault appears.

When the project includes a traffic signal system, the Contractor shall conduct tests
noted in

Section 8-20.3(14)D

. The Contractor shall provide the Engineer a minimum of

5 days advance written notice of the proposed traffic signal turn-on date and time. The
traffic signal turn-on procedure shall not begin until all required channelization, pavement
markings, illumination, signs, and sign lights are substantially complete and operational
unless otherwise allowed by the Engineer. The Contractor shall provide traffic control
to stop all traffic from entering the intersection. The Contracting Agency electronics

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Illumination, Traffic Signal Systems, Intelligent Transportation Systems, and Electrical

technician will program the controller and enter the timing data, then turn the traffic
signal system to its flash mode to verify proper flash indications. The Contracting Agency
electronics technician will then conduct functional tests to demonstrate that each part
of the traffic signal system, illumination system, or other electrical system, functions as
specified. These demonstrations shall be conducted in the presence of a Contracting
Agency electronic technician, the Contracting Agency electrical Inspector, and Regional
Traffic Engineer or his/her designee. The Contracting Agency electronics technician will
then turn the traffic signal to stop and go operation for no less than one full cycle. Based
on the results of the turn-on, the Engineer will direct the Contracting Agency electronics
technician to either turn the traffic signal on to normal stop and go operation, to turn the
signal to flash mode for a period not to exceed 5 calendar days, or to turn the signal off
and require the Contractor to cover all signal displays and correct all deficiencies.

If the Contractor is directed to turn off the traffic signal, the Contractor shall schedule
a new turn-on date with the Engineer in accordance with the previously mentioned
procedures.

Unless approved by the Engineer no change to signal stop and go operation will be
allowed between 6:00 a.m. to 10:00 a.m. and 2:00 p.m. to 7:00 p.m. on Monday through
Thursday, nor will signal operation changes be allowed on Friday, weekends, holidays, or
the day preceding a holiday.

8-20.3(12) Painting

All painting required shall be done in conformance with applicable portions of

Section 6-07

8-20.3(13) Illumination Systems

8-20.3(13)A

Light Standards

Light standards shall be handled when loading, unloading, and erecting in such a manner
that they will not be damaged. Any parts that are damaged due to the Contractor’s
operations shall be repaired or replaced at the Contractor’s expense.

Light standards shall not be erected on concrete foundations until foundations have
set at least 72 hours or attained a compressive strength of 2,400 psi, and shall be raked
sufficiently to be plumb after all load has been placed.

Slip base installation shall conform to the following:
1. The slip plane shall be free of obstructions such as protruding conduit or anchor

bolts. The anchor bolts, and other obstructions shall terminate at a height below
the elevation of the top of the slip plate. Conduit shall extend a maximum of 1 inch
above the top of the foundation, including grounding end bushing or end bell
bushing.

2. Washers in the slip plane shall be placed between the slip plate and the keeper plate.

Illumination, Traffic Signal Systems, Intelligent Transportation Systems, and Electrical

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3. Anchor bolts shall extend through the top heavy-hex nut two full threads to the

extent possible while conforming to the specified slip base clearance requirements.
Anchor bolts shall be tightened by the Turn-of-Nut Tightening Method in accordance
with Sections

6-03.3(33)

and

8-20.3(4)

4. Clamping bolts shall be tightened in accordance with Sections

6-03.3(33)

and

8-20.3(4)

. The clamping bolts shall be tightened to the specified torque, plus or

minus 2 percent, in two stages using an accurately calibrated torque wrench before
erecting the light standard. Except as otherwise specified, the Contractor shall install
1-inch diameter clamping bolts in all slip bases to a torque of 95 foot-pounds.

5. The galvanized surfaces of the slip plates, the keeper plate and the luminaire base

plate shall be smooth, without irregularities, to reduce friction and to prevent
slackening of bolt tension due to flattening of the irregularities.

6. Anchor bolts damaged after the foundation concrete is placed shall not be repaired

by bending or welding. The Contractor’s repair procedure is to be submitted to
the Engineer for approval prior to making any repairs. The procedure is to include
removing the damaged portion of the anchor bolt, cutting threads on the undamaged
portion to remain, the installation of an approved threaded sleeve nut and stud,
and repairing the foundation with epoxy concrete. Epoxy concrete shall meet the
requirements of

Section 9-26.3(1)B

7. The grout pad shall not extend above the elevation of the bottom of the anchor

plate.

8. Wiring for slip base installation shall conform to details in the

Standard Plans

Breakaway coupling installation shall conform to the following:
1. At existing foundations, the anchor nuts, pole, grout pad, and leveling nuts shall

be removed. Conduits shall be cut to a maximum height of 2 inches above the
foundation including grounding end bushing or end bell bushing. Paint, conforming
to

Section 9-08.1(2)B

, shall be applied to the cut conduit that has been threaded.

Anchor bolts that are damaged shall be repaired with approved sleeve nuts as noted
under slip base installation procedures.

2. All existing anchor bolts shall be cut off 2½ to 3 inches above the foundation. At new

foundations, the anchor bolts shall be installed with top of bolt 2½ to 3 inches above
the foundation.

3. Couplings shall be installed to within ⅛ to ⅜ inch of the foundation. Couplings shall

then be leveled.

4. The pole shall be set and plumbed; and washers, nuts, and skirt installed per

manufacturer’s recommendations.

5. The conduit installed in a luminaire foundation shall not exceed 1 inch, trade size.

Slip base insert installations shall conform to details in the

Standard Plans

, and shall

conform to items 1 through 8 above for slip base installation, except that the specified
torque for the ⅞-inch diameter clamping bolts shall be 50 foot-pounds.

Standard Specifications for Road, Bridge, and Municipal Construction 2020 (M 41-10) - page 79