The following information
does not alter or supersede the Contract Documents. It is provided as a guide for ODOT personnel
assigned to a project to help them with their work.
Electrical construction work
must adhere to the Contract Documents which commonly include proposal notes,
project plans, Standard Drawings, and Construction and Material
Specifications. In addition, there may
be building or electrical codes or change orders that must be followed.
Only Contractors prequalified
by the ODOT Office of Contracts for Work Type 43 ‑ Highway Lighting shall
be allowed to do the highway lighting items of work on the project.
Contractors are prequalified
for specialized work types. They bring
expertise to the project and an independent perspective from the project
management team. As the Contractor
reviews plans and specifications, he wants to ensure that he can install
material that will ultimately operate as the designer intended. The Contractor relies on the Engineer to
guide the project, to approve materials and work, and to ensure that he will be
paid for work completed. It is important
to remember that even when the roles of the project team and the Contractor
conflict, successful completion of the project relies on all those involved and
the maintenance of good working relationships.
The Contractor is to notify
all utilities before construction work begins.
Names and addresses of these utilities are given in the project
plans. It is the Contractor’s responsibility
to contact the Ohio Utility Protection Services
(1‑800‑362‑2764) to have utility locations marked in all
areas where digging is involved.
When there is a question
regarding the intent of the plan, the Engineer should:
1. Define the discrepancy or ambiguity.
2. Determine if more than the highway lighting is
affected.
3. Identify the standard drawings and specification
pertinent to the situation.
4. Determine potential solutions.
5. If the issue involves the location of the luminaires
or light poles, the mounting height of the luminaries above the pavement, the
luminaire to be used or the lamp to be used, the Engineer should consult ODOT’s design office and the Designer to ensure that the
performance goals for the lighting system will still be met by the solution
under consideration.
6. Consider the maintenance of the installation if the
solution is implemented. Will parts not
normally stocked by the maintaining agency be required, or will tools and
equipment not normally at the disposal of the maintenance crews be required, or
will special training of the workers be required?
7. Evaluate potential solutions for safety. Consider measures needed to keep errant
vehicles from striking the item, the danger to those who must maintain the
installation, and the danger to traffic from the maintenance activities.
8. Determine if applicable codes and regulations will be
met. Commonly involved will be the
National Electric Code, The National Electric Safety Code, and Utility Company
requirements. There may also be state
and local building codes.
Highway lighting items are
found in 625
with detailed descriptions of materials in 725.
In general, all material
furnished shall be new and of first quality, unless otherwise noted in the
plans, and shall be identified either by a permanently attached name plate or
by an indelible marking.
Before installation, all
material shall be checked to determine that it is indeed the material that has
been specified, the appropriate material process has been completed, and all
paperwork is in hand.
Four procedures are commonly
used to ensure that the correct materials are installed.
1. Qualified
Products List (QPL).
2. ODOT Plant Sampling and Testing Plan (TE‑24
Certification).
3. Certified Drawings or Certified Catalog Cuts.
4. Project Inspection of Material.
Lighting material which may
be on a Qualified
Products List:
1. Pull box.
2. Junction box.
3. Conduit.
4. Wire and cable.
5. Ground rod.
6. Photocell.
The Office
of Materials Management maintains the Qualified
Products Lists. The Engineer can
verify that the material is on a Qualified
Products List (QPL) through ODOT’s
SiteManager.
After verifying that the material being supplied is that specified by
the Contract and on such a list, the project may accept the material.
Lighting material for which
TE‑24 Certification may be obtained:
1. Pull box.
2. Junction box.
3. Anchor bolt.
The ODOT Plant Sampling and
Testing Plan (TE‑24 system) is administered by the Office
of Materials Management. This system
was designed to allow certain material to be sampled, tested, approved, and
stocked for future use on ODOT projects.
The material is inspected at the manufacturing or distribution
site. Each approved lot of material is
assigned a certification number and documented on Form TE-24. Material from the approved lot may then be
transferred directly to an ODOT project or it can be transferred to other
warehouses, such as a Contractor’s storage facility, and then transferred to a
project at a later date.
Lighting material requiring
Certified Drawings or Catalog Cuts:
1. Luminaires.
2. Luminaire supports (towers, lowering devices, poles,
bracket arms).
3. Power service equipment.
4. Portable power units.
5. Temporary lighting systems.
The Contractor shall submit
two copies of shop drawings or catalog cuts prior to the installation of the
material. The submittal ensures that the
state has a good record of the material installed should there be any question
about the material meeting criteria or should additional or replacement units
be required.
Each submittal shall identify
the project and the bid reference number under which the item is being
provided. Drawings or catalog cuts shall
be clearly marked by circling or underlining to indicate the exact item and
options being supplied. If a given item
is to be supplied under multiple bid item reference numbers, separate and
complete documentation packages shall be submitted for each bid item reference
number. If multiple items are to be
supplied under a single bid reference number, all the items to be supplied
under said reference number shall be submitted as a package. The Contractor’s cover letter for each
package is to certify in writing that each manufactured item in the package
conforms to all contract requirements for that item.
The submittal of certified
drawings or catalog cuts does not relieve the Contractor from furnishing
additional information concerning the material deemed necessary by the state.
The following materials are
normally manufactured to standards that meet ODOT criteria and therefore do not
have a QPL, do not normally have a TE-24, and shop drawings or
catalog cuts are normally not required:
1. Exothermic welds.
2. Insulating varnish.
3. Split bolt connector.
4. Expansion fittings.
5. Connector kits.
6. Splice kits.
7. Copper crimps and compression connectors.
8. Light pole decals.
9. Circuit identification tags.
10. Cable grips.
11. Wood service poles.
12. Fuses for control center and connector kits.
13. Photoelectric cell and bracket.
14. Secondary lightning arrestor.
15. Guy anchors and anchor rods.
16. Weather heads.
17. Watertight hubs.
18. Remote ballast enclosures and mounting brackets.
Project inspection of
material is used to verify that the material at hand is listed on a QPL or described on a TE-24 for which certified shop
drawings or catalog cuts have been received and that the material complies with
the requirements of the Contract Documents.
For material not on a QPL, which does not have a TE-24, and for which shop
drawings or catalog cuts are not required, the project inspection of material
is limited to comparing the material at hand with the requirements of the Contract
Documents.
A luminaire consists of a
housing which contains a reflector, refractor, lamp socket, and lamp. Unless
otherwise specified, the housing will also contain the ballast components (core
and coil, capacitor, starter) required for the lamp being used. The housing may
have optional components, such as fuses or a photocell when specified. The housing
is fitted with the necessary clamps or other provisions for attaching the
luminaire to its support and terminal block for the incoming power.
Verify that the luminaire
installed at each location is one of the luminaires listed in the plan for that
location. Verify that the distribution,
lamp type, and lamp wattage are as specified in the plans. Instructions packed with the luminaire will
explain the distributions that the luminaire is capable of producing and how to
set any adjustments in the luminaire to provide each distribution. Verify that ballast is compatible with the
circuit voltage and lamp.
The conventional luminaire
used by ODOT is also known in the trade as an “Ovate” or “Cobra Head”
fixture. It may be equipped with a flat
or a dropped style refractor as specified.
Verify that the luminaire is
properly leveled according to the instructions packed with the luminaire.
This luminaire reminds one of
a floodlight.
Verify that the “tilt” has
been set as specified in the plan according to instructions packed with the
luminaire. Verify that the luminaire is
oriented “normal” to the line of survey for the roadway being lighted unless the
plans stipulate otherwise.
These luminaires are mounted
on tall structures equipped with devices to bring the luminaires to ground
level for servicing.
Verify that the luminaire is
not “twisted” with regard to its bracket arm.
There are three distributions commonly used. If the luminaire has a rotatable refractor,
verify that it has been aligned properly.
Low mast luminaires are the
same luminaire as a high mast luminaire, but installed as a fixed unit on a
pole of more traditional height.
Verify that the luminaire is
not “twisted” with regard to its bracket arm.
There are three distributions commonly used. If the luminaire has a rotatable refractor,
verify that it has been aligned properly.
Underpass luminaires are used
to light roadways beneath bridge decks.
Commonly they are wall mounted on a pier cap or abutment. Sometimes they may be ceiling mounted on the
underside of the deck or to a panel attached to the deck supporting beams or
pendant mounted on suspension pipes attached to the structure. Occasionally they will be post top mounted on
short poles.
Verify that the luminaire has
been attached to the structure at the location and in the manner specified.
Verify that the lamp is one
of the brands listed in the plan. Verify that the lamp type and wattage is
compatible with the luminaire and its ballast.
Unless otherwise specified, for a particular installation, the lamps are
to have clear envelopes. Do not
substitute lamps with “frosted” envelopes.
Verify that the installation date has been properly marked on the base
of the lamp. Instructions packaged with
the lamp explain how to use the dating provision built into the base.
The inspection of the
supports (poles, arms, towers, lowering devices, brackets, etc.) consists of
two phases: (1) inspection of the components and (2) inspection of the
completed assembly. While these may be
done together, it is better if the components are inspected upon arrival at the
project since there is more time to obtain replacements or correct faults.
Three areas are examined in
this phase: welding, galvanizing, and compliance with shop drawings.
Examine each weld for the
following:
1. Each of the welds called for by the certified shop
drawings is present and there is no weld present that is not shown on said
drawings.
2. There is no misalignment of the parent material being
joined by the weld.
3. There has been no warping of the parent material by
the weld.
4. Each weld is of the type, size, and continuity shown
on the shop drawings.
5. Each weld is of full cross-section without excessive
concavity or convexity.
6. There is no over filling or cratering at either the
beginning or end of the weld.
7. There is no undercutting (a shallow groove melted into
the base metal adjacent to a weld and left unfilled by weld metal) along any
weld.
8. There is no porosity (pitting or pinholes) in any
weld.
9. There is no crack or discontinuity in either the base
metal or weld material along any weld.
Examine the galvanizing for
the following:
1. There are to be no spots where the galvanizing is
missing or loose and can be flaked off with a penknife.
2. There should be no ash that has been picked up from
the top of the bath which usually appears as coarse lumps.
3. There should be no pimples from entrapped bath scum
particles.
4. There should be no blisters from hydrogen gas absorbed
during pickling being released and rupturing the surface of the galvanizing.
5. There should be no flux inclusions from flux picked up
from the top of the bath during dipping and burned on during immersion.
6. There should be no lumps or runs of excess zinc from
delayed run‑off of molten metal trapped near surface discontinuities,
such as joints, seams, or holes as the part was lifted from the bath.
7. There should be no rust stains from impurities from
the pickling process weeping at seams and folds.
8. There should be no general overall roughness from over
pickling or of excess zinc bath temperature and/or immersion time.
9. There should be no patches of dull, gray coating from
slow cooling of heavier cross-sections of the part after immersion.
10. The galvanizing should have a uniform appearance.
Excessive galvanizing faults,
gross imperfections, or overall poor workmanship may be cause for rejection of
the support. Minor scratches in
galvanized surfaces can be accepted.
Supports are frequently
shipped to the job site and stored prior to assembly and erection as components
which give opportunity for the components to get mixed up leading to improper
assemblies since the basic design often does not prevent errors. Therefore, prior to beginning the assembly of
a given support, it is necessary to check the major dimensions of the various
components against the shop drawing for the support to verify that this has not
occurred.
On poles, verify the length,
base diameter, top diameter, and wall thickness of each pole, or section of the
pole, for poles shipped in multiple sections that are field assembled. Verify the length, width, and thickness of
the base plate along with the bolt circle diameter, bolt hole size, and number
of anchor bolt holes provided.
On bracket arms for
conventional supports, verify the arm length and arm rise.
On lowering devices, verify
the diameter of the luminaire mounting ring and number of luminaire arms on the
ring. Also, verify the length of the
power cord along with the wire size and number of conductors in the cord.
Verify the diameter and length of each piece of hoisting cable.
Support components stored in
the field should be kept off the ground to prevent finish blemishes where the
component lay in contact with a damp surface earth or water. Support components and assembled supports
should be loaded, transported, unloaded, stored, and erected in a manner
avoiding damage to the factory applied surface finishes.
On multi-piece poles, verify
that the sections to be assembled are the correct pieces for the pole at
hand. Before tightening each telescopic
joint between the sections, verify that the sections are properly oriented and
that the male section has been marked to indicate when full insertion has been
achieved. Verify that the process used
for tightening the joint between sections is approved by the pole manufacturer
and that the pole is not bent during the tightening process.
On each steel light pole used
with an aluminum transformer base, verify that both the bottom of the pole base
plate and the top of the transformer base were given a coat of zinc rich paint
prior to assembly.
On each light pole, verify
that the cable grip in the light pole is properly installed as shown in SCD
HL‑10.12 to prevent damage to the pole and bracket cable.
On each light tower, verify that
the luminaire ring has the correct number of mounting arms and that each arm is
attached such that when the tower is erected, the arms will be in the positions
relative to the roadway as shown on SCD
HL-10.31. If the lowering device is
equipped with top laches, verify that when the luminaire mounting ring is fully
raised and latched, the latch indicator on each latch will be in the “extended”
or “visible” position. Verify that all
moving parts on the head frame assembly and hoist mechanism have been
lubricated in accordance with the manufacturer’s instructions.
Verify that all parts are in
place and all fasteners have been properly installed according to the
manufacturer’s instructions.
Verify that each hand hole
door or cover closes with no excessive gaps.
Verify that a light amount of
anti‑seize or grease lubricant has been worked into the threads of each
fastener which hold each removable cover in place.
Prior to erection, verify
that nuts can be easily turned by hand onto the threads of each anchor bolt.
When leveling nuts are to be
used, verify that the leveling nuts are level before beginning the lift to set
the support.
Each support should be lifted
and set by crane with the hoist line attached at a point as far above the
support’s center of gravity as possible,
with a tethering cable from the lifting point to the base of the pole. The lifting point on poles made up of
sections slip fitted together should be above the uppermost joint. Hoisting should be smooth and continuous
without abrupt jerks. Light tension
should be maintained in the hoist lines until an anchor nut has been threaded
onto each anchor bolt far enough that the bolt is projecting though the nut by
a full thread.
Verify that each support with
a transformer base has been plumbed using leveling shims approved by the base
manufacturer, installed between the base and the foundation according to the
base manufacturer’s instructions and limitations and that the anchor nut on
each anchor bolt has been properly tightened.
Verify that each support with
an anchor base installed directly on a foundation, without leveling nuts, has
been plumbed using leveling shims approved by the pole manufacturer. Each
support is installed between the base and the foundation, according to the pole
manufacturer’s instructions and limitations, and the anchor nut on each anchor
bolt has been properly tightened.
Verify that each support with
leveling nuts is plumbed by adjusting the leveling nuts. Verify that both the
anchor nut and the leveling nut on each anchor bolt are properly tightened.
Verify that a light tower has
been plumbed early in the morning when the heat effect from the sun is at a
minimum.
Verify that each support has
been plumbed when there is no appreciable wind.
Verify that the space between
the top of the foundation and the base of the support has not been grouted.
When a high mast support
(light tower) is equipped with a lowering device that has top latches, verify
that the ring engages all latches simultaneously. This is often referred to as
“leveling” the ring. It should be done
following the manufacturer’s directions.
Generally the procedure is to place a block on each hoisting cable which
is attached to the ring a few inches above the ring in such a manner that the
block will slide along the cable when the block contacts the portion of the
mechanism at the top of the tower. The ring is then raised until all blocks
have made contact, but not fully raised.
The ring is lowered and the distance between each block and ring is
measured. Hoisting cables are adjusted to make the measurements equal. The
process is repeated until no further adjustments are required. The blocks are removed and the lowering
device operated several times through its full cycle watching all latches for
proper operation.
Verify that support
identification decals have the proper legend and the decals are located
approximately 7 feet (2.1 m) above the base of the pole facing oncoming
traffic.
Foundation inspection
normally consists of three parts: location, excavation and concrete placement.
After the location of each
foundation is staked, verify that the location is specified in the plan and
that Ohio Utility Protection Service and all utilities in the area have been
allowed at least 48 hours to mark their utility locations relative to the
proposed foundation. Verify that the
location appears logical. Be alert for
the following:
1. Installing the lighting item at the staked location
will require removal of vegetation that shields adjacent property owners from
the highway.
2. Installing the lighting item at the staked location
will locate the item at the top of the back slope, in a cut cross-section, or
at the bottom of the fill in a filled cross-section where guardrail is to be
used to keep errant vehicles from going down the slope.
3. Installing the lighting item at the staked location
will place the item under an overhead utility line or over an underground
utility line.
4. Installing the lighting item at the staked location
will require a graded access drive for the construction that has not been
addressed in the plan.
The designer should be
consulted prior to relocating any support more than 10 feet (3.0 m) or if two
or more adjacent supports need to be relocated.
Foundations are to be placed
only in undisturbed soil or compacted embankment.
If a minor cave‑in
should occur, the Contractor may, with the approval of the Engineer, continue
to excavate using sleeving or casing. When bedrock is encountered, the Engineer may
reduce the specified foundation depth.
If construction crews must
leave the job site with a hole unfilled, it shall be covered and marked with
cones, barrels, or warning tape.
Verify that the top of the
foundation will be at the proper elevation.
Tops of foundations shall be
finished smooth and level to enable proper plumbing of the light pole.
Verify that the anchor bolts
are of the correct size and number and that each bolt is securely held in the
correct position. The use of an anchor
bolt setting template is encouraged.
Verify that each anchor bolt will project the proper distance from the
foundation.
Verify that conduit ells are
present and that each ell is of the correct size and material and properly
oriented.
Verify that all reinforcing
bars are present and that each is of the correct size and shape.
Verify that all items to be
cast into the foundation, along with any forming aids, are secured in such a
manner that they will not move out of position during the placement of
concrete.
Verify that water encountered
in the foundation excavation is pumped out before concrete placement. If this is not feasible, verify that the
concrete is placed by the tremi‑tube method.
Verify that the concrete is
of the proper design, has been properly mixed, has the correct slump, and is
properly handled during placement.
Verify that the concrete is vibrated to eliminate voids.
Verify that the top of the
foundation is properly finished and that the concrete is properly cured.
Verify that each junction box
is of the correct size and material and securely fastened in the correct
location. Verify that a light amount of
anti‑seize or grease lubricant has been worked into the threads of each
fastener holding the cover in place.
Verify that each pull box is
of the size and material specified.
Verify that each pull box is
at the planned location unless the planned location puts the box in a low spot
with respect to the surrounding surface.
In such cases, notify the Engineer so that the Engineer, in consultation
with the designer, may attempt to move the box to a location where it will be
less likely to hold water.
Verify that a light amount of
anti‑seize or grease lubricant has been worked into the threads of each
fastener holding the cover in place.
Verify that each conduit run
is of the correct size and material.
Verify that each cut end on
each piece of conduit is reamed to remove rough edges.
Verify that all field cut
threads on galvanized conduit have been coated with zinc rich paint.
Verify that each expansion or
deflection fitting has a bonding strap for ground continuity when used with
metal conduit.
Verify that each conduit run
has been properly fastened in place.
Verify that the Contractor
shall check each run of conduit by rodding (pushing a mandrel through the empty
conduit) or pulling a cleaning puck through the conduit.
Verify that each run of
conduit being left empty for future use contains a No. 10 AWG
pull wire or equivalent.
Verify that each end of each conduit
run is terminated either in a box connector that contains an integral bushing
or with a separate bushing to protect cable pulled into the conduit.
Verify that the trench did
not deviate more than 6 inches (150 mm) from the designated line, unless such
deviation has been approved by the Engineer.
Verify that the sidewalls and bottom of the trench do not have any
protruding sharp rocks.
When duct-cable is installed
in the trench, verify that the backfill material within 2 inches (50 mm) of the
duct-cable does not contain pieces larger than 1/2 inch (13 mm).
Verify that the backfill is
placed in compacted layers exceeding no more than 4 inches (100 mm) in
thickness.
When caution tape is
specified, verify that the tape is installed 6 inches to 8 inches (150 to 200
mm) below grade.
Power service includes all
equipment from the connection point to the utility company to the beginning
point of the individual lighting circuits.
Verify that the power service
location will be readily accessible to both maintenance personnel and utility
company personnel. There should be a
safe parking area for service vehicles since the site will be visited
regularly. The location should not be
prone to standing or flowing water during rain events or to drifting snow. If the location appears unreasonable, involve
the designer and utility company as soon as possible, since moving a power
service often means redesigning the lighting circuits.
Verify that the Contractor
has been in touch with the utility company and is aware of any utility company
requirements which may differ from the requirements of the Contract Documents.
Verify that the photocell is
facing the north sky, unless otherwise stipulated by the plan, and that no
artificial lighting source is disrupting its proper operation.
Verify that the conduits are
neatly routed and fastened securely in place.
Verify that enclosures are
securely mounted.
Verify that enclosure covers
are in place and fasteners for the covers have had anti-seize or grease worked
into the threads.
Verify that moving parts of
the switch gear have been lubricated and operate smoothly.
Verify that no debris has
been left in enclosures and that the wiring in each enclosure is neat, orderly,
and tied into place where appropriate.
The conducting portions of
those items which contain electrical conductors are to be connected to each
other and to earth electrodes to lessen the chance of injury and damage from
unwanted electrical currents. Connecting
the various conducting portions together to form a continuous path for the flow
of stray electrical currents, often referred to as bonding in ODOT’s projects, is generally incidental to the
construction. Installation of the earth
electrodes and the connection of the conducting portions to those electrodes is
often referred to as grounding, and in ODOT’s
project’s payment is somewhat related to the electrodes installed.
Verify that the specified
ground rods have been installed. When
additional rods have been added to lower the resistance, verify that the
installation of each rod was approved prior to its installation.
Verify that the connection
between the ground rod and the grounding cable is an exothermic weld. When additional rods have been added to
reduce the resistance, verify that the additional connections are exothermic welds.
The normal ground rod item is
for one rod, driven into earth, and the lead between the rod and the first
connection and associated connections.
The earth resistance is then checked.
When said resistance exceeds the specified limit, an additional rod is
to be driven and connected to the first. The earth resistance of the pair is
then checked. The process is repeated until the resistance of the group is
lower than the specified limit. Payment
is then made for each rod installed at the “per rod price.”
ODOT has reserved the right
to approve the use of each additional rod before it is installed and may
decline to install additional rods, thereby stopping the process at any
point. When ODOT stops the installation
of additional rods, it may decide to take another course of action to lower the
earth resistance. If no additional
action is taken, then by default, the earth resistance becomes acceptable as it
stands.
An exothermic weld often has
a rougher surface texture on the weld metal than one may be used to seeing, but
the weld is not to have other signs of a poor quality weld, such as porosity,
cratering, cracking, or undercutting.
Verify that each grounding
electrode is acceptable before structure construction makes modification of the
electrode, or the installation of additional electrodes, impractical. Remember, if some of the electrodes are
driven rods that such rods are incidental to the structure grounding system,
not separate items. However, if due to
high resistance, additional rods are driven, those rods are not incidental to
the structure grounding system.
Verify that the necessary
bonding jumpers are in place and functioning correctly before structure
construction makes the installation of additional jumpers impractical.
Structures present special
needs. Not only is it impractical to
have a separate ground rod for each light pole or similar item mounted upon the
structure, but there are also elements of the structure itself that need grounding. The normal practice is to use bonding jumpers
to connect all exposed metal items together and therefore to the several
electrodes which frequently utilize the main conducting portions of the
structure as the main grounding buss.
This means that electrodes are often under footers and bonding jumpers
are frequently embedded in the structure.
If something is left out or does not function as intended, and it is not
discovered until the final stages of construction, the grounding can become
expensive, unsightly, and less than desired.
Unfortunately, structure designers all too often include little in the
way of specific details for the structure grounding. Therefore, it is imperative to constantly
think ahead to fully understand where each electrode and jumper is to be
located and to verify that it is in place and functions correctly at each
stage.
Verify that all of the
conducting items which contain the conductors of each circuit are bonded to
form a continuous path back to the source of the circuit.
At light poles, verify that
metal conduits entering the base of the pole are bonded to the pole.
At pull boxes, verify that
the metal conduits entering the pull box are bonded together and the metal lid
and lid frame are bonded to the metal conduits.
At junction boxes, verify
that the metal conduits entering the junction box are bonded to the box.
At the expansion and
deflection joints in conduits of conducting materials, verify that a bonding
strap has been install across the joint.
When non-conducting conduit
or duct is used, verify that a grounding conductor has been installed to
provide for the continuous grounding path.
Field wiring of highway
lighting circuits is broken into three types.
Pole and bracket cable is the
insulated, single conductor used in a light pole (but not in a light tower) to
connect from the distribution cable, up the pole, and out the bracket arm to
the light fixture. In a tower, the electrical wiring from the base of the tower
to the luminaires is a component of the lowering device.
Verify that each run of cable
is of the size and type specified. The wire size and insulation are to be
indelibly marked on the insulating jacket at frequent intervals along the
length of the cable.
Verify that each run of cable
is installed in a continuous piece without inline splices between the
terminations shown on the plan.
Verify that the insulating
jacket wasn’t nicked, nor portions shaved away, as the cable was pulled into
place.
Verify that the cable was not
stretched as it was pulled into place.
If the cable can be pulled back and forth by hand enough to move both
ends, stretching probably did not occur.
Verify that a cable support
was installed at the upper end of the vertical run of cable up the pole.
Verify that there is enough
length on each end of the run for the cable to be routed properly to its
termination and still remain slack.
Distribution cable is the
insulated, single conductor used to construct lighting circuits from the
control equipment of the power service to the disconnect kits of a light pole,
the terminal block of a light tower, or the disconnect switch for underpass or
sign lighting.
Verify that each run of
distribution cable is of the size and type specified. The wire size and
insulation are to be indelibly marked on the insulating jacket at frequent
intervals along the length of the cable.
Verify that each run of cable
is installed in a continuous piece without inline splices between the
terminations shown on the plan.
Verify that the insulating
jacket wasn’t nicked, nor portions shaved away, as the cable was pulled into
place.
Verify that the cable was not
stretched as it was pulled into place.
If the cable can be pulled back and forth by hand enough to move both
ends, stretching probably did not occur.
Unfortunately, for the larger wire sizes and the longer runs commonly
encountered in highway lighting circuits, the cable cannot be pulled by
hand. The most common indication of
stretching is when the length of pulling lead exiting the raceway is greater
than the length of cable entering the raceway, or the pulling forces are
greater than normally encountered, both of which are not easily detected by
anyone other than experienced installers.
Verify that there is enough
length on each end of the run for the cable to be routed properly to its
termination and still remain slack.
All cables shall be labeled
in accessible enclosures (pull boxes, hand holes, transformer base, device
housing, etc.). A minimum of 5 feet (1.5
m) of extra cable shall be provided for each conductor at all terminal points.
Duct-cable consists of insulated
conductors, of the type used for distribution cable, installed into a duct and
shipped as an assembly to the project. It is used in place of conduit and
distribution cable to speed the installation of underground circuits.
Verify that the temperature
of the duct‑cable was above 32 °F (0 °C) throughout the installation
process.
It is permissible to install
duct-cable when the outdoor air temperature is actually below those
temperatures, but the Contractor must obtain authorization from the Engineer. The Contractor shall submit, in writing, his
method of heating the duct-cable and maintaining the duct-cable at a uniform
temperature throughout the installation process. To ensure that the duct-cable is heated
uniformly, the heating process shall keep the temperature of the duct-cable
above 32 °F (0 °C) for a minimum of 24 hours prior to installation. Under conditions, such as the preceding,
where the temperature of the duct-cable can be expected to vary widely during
the installation process, the expansion and contraction of the duct-cable must
be taken into consideration. Typically,
the duct-cable length will decrease or increase 1 foot per 1,000 feet (0.3 m
per 300 m) for each 10 °F (5.6 °C) decrease or increase in temperature.
Verify that the duct of the
installed duct-cable extends out of any conduit sleeve through which it passes
enough to allow for the expansion and contraction in the duct due to seasonal
changes in temperature. Typically a
projection of 2 to 3 inches (50 to 75 mm) is appropriate at the usual
installation temperatures for the lengths of run typical in ODOTs
installations.
As received on the reel from
the manufacturer, it will appear that the cables inside the duct and the duct
are equal in length, but in reality the cables are shorter than the duct. In order to reel the assembly onto the
shipping spool, both the cables and the duct were anchored to the spool. As the
duct cable assembly is unrolled from the shipping spool, the cables will be
drawn into the duct resulting in empty duct at the start of the run. For the assemblies typically used in ODOTs projects, leaving 25 feet (7.6 m) of duct for each
1,000 feet (300 m) of run to be installed, in addition to that required as
slack for connections at the start of the run, will compensate for this. At the end of the run, only the slack amount
for connections is required.
Verify that the insulating
jacket of each cable within the duct has not been damaged when the duct was
stripped to allow the connections to be made.
Often the length of duct to be stripped is such that no protection can
be slid over the cables and into the end of the duct, which means that the
cables within are saved from damage only by the skill of the person stripping
the duct.
When a duct cable assembly
has been passed through a conduit sleeve, verify that the duct has been sealed
to each end of the sleeve by means of a molded boot or wrapped sealing pad.
Verify that the seal
installed between the cables and the duct is installed in the same location and
in the same manner as outlined under the installation of distribution cable
into conduits.
Verify that there is enough
length on each end of the run for each cable to be routed properly to its
termination and still remain slack.
At each access point (pole
base, pull box, junction box, switch gear enclosure, etc.) each conductor of
each run of the field wiring (pole and bracket cable, distribution cable,
duct-cable) of each circuit is to be identified by applying a tag to the
conductor indelibly marked to indicate the circuit and the use of that
conductor within the circuit.
This covers the connection of
the field installed wire and cable to other such wire and cable and to the
various items of equipment.
When the circuit conductor is
of a larger size than the device terminals can accommodate, verify that the connection
has been made by splicing a short piece of smaller wire onto the end of the
large wire and then connecting the smaller wire to the device terminal. The smaller wire is normally identical to the
larger wire in all aspects except for size.
The smaller wire must be large enough to carry the current that the
circuit protection will allow. It is not
acceptable to cut back some of the strands of a conductor, so that the
remaining stranded will fit into the terminal.
Verify that the die in the
compression tool was for the connector applied. The connector is sized to match
the wire to which it was applied and the tool used was of a type that did not
release the connector from the die once compression started until full compression
was achieved.
Verify that the internal
connector is properly applied to the conductors.
Verify that the insulating
cover was cut to proper step for a snug fit over the insulation on each entry
to the housing.
Verify that the internal
parts are all present in good condition and are fully seated into the housing.
Verify that the male half of
the housing is a snug fit and fully inserted into the female half of the
housing.
Verify that a thin coating of
the kit manufacturer’s approved, non-conducting grease has been used at the
joint between the two halves of the housing, between the housing and each cable
entering the housing, and on other internal parts, as show in the
manufacturer’s instruction, which allow the parts to slide smoothly into place
and help seal out water.
Verify that there are no
sharp bends in each cable where the cable enters the housing sufficient to
cause the housing to pull away from the insulating jacket on the cable.
When the kit is to contain a
fuse, verify that the fuse is of the proper ampacity.
Where the kit contains bolted
connections, verify that the connections have been properly tightened before
the housing was closed.
Verify that there is
sufficient slack in the cables being connected to permit bringing connector
kits outside of the pole, transformer base or junction box in which it is
housed for servicing.
Verify that the internal
connection is via a proper crimp compression connector.
Verify that the mold
surrounding the connection is completely filled with resin.
Verify that the connection is
positioned within the mold such that the resin properly surrounds the
connection.
Verify that there are no
voids in the resin.
Verify that no fillers have
been used.
Verify that the resin has
properly set.
There are a number of tests
normally utilized to ascertain that the lighting installation has been well
constructed and is in good operational order. For a particular test to have
meaning it must be properly conducted and the results properly interpreted.
Verify that the equipment
used to conduct the test is in working order and calibration.
Verify that each specific
grounding electrode meets the requirements of the earth resistance test.
The first key to conducting a
successful test of a grounding electrode is to understand what constitutes the
electrode. A single driven rod is an
electrode. When that rod fails the earth
resistance test and another rod is added, the electrode then becomes both rods
together. However, in the case of a
light tower where two rods are typically specified, the initial electrode is
the two rods together rather than each rod separately. In structure grounding, the cluster of driven
piles at the end of a pier footer should be considered as a single electrode,
with the cluster at the other end of that same footer considered as a separate
electrode. A continuous grid of mesh,
bars, or cables laid beneath a footer is one electrode, but separate grids
under different portions of the same footer are separate electrodes. Wires buried in a radial pattern from a
single pole constitute an electrode.
The second key to successful
ground resistance is to understand the limitations of the various test
instruments and procedures. The chosen
procedure must be appropriate for both the electrode under test and the
conditions in which the electrode is installed and the instrument must be
capable of producing valid results for the situation at hand.
The key to the proper checking
of circuit continuity is to remember the objective and to test one conductor at
a time. The objective is to see that the
conductor is connected to the desired device point and the conductor has not
been connected to any other devices. The
difficulty is that the devices are scattered over a large area, thus, requiring
the other conductors of the same circuit to be used as returns for the test
signal. For the test to be of use, the
testing must start at one node in the circuit and test all connections along an
isolated link from that node. Additional nodes and links are then added one at
a time and the continuity of the conductors rechecked until the entire circuit
has been verified.
This test is designed to
verify that the insulation of each conductor in the circuit, and permanent and
bolted connections in that conductor, are in good conditions to impress a much
higher than normal voltage on the conductor using the change in leakage current
over time. Care must be used not to impress the test voltage on devices
normally connected by the circuit since the devices would probably be damaged. Since the other conductors in the circuit
must often be used as the return path, it is necessary to use care to ensure
that other conductors are not damaged while serving as signal returns and
careful interpretation of the results to determine whether the leakage is from
a conductor failing the test or from a failure in the return path.
This test is simply repeated
operation of the lowering device on a light tower to verify that is operates
smoothly and correctly throughout its full range cycle of motions.
The test uses the concept,
“infant mortality,” to determine if the equipment is likely to operate
satisfactorily throughout the projected life of the installation. The concept is that the equipment is most
likely to fail from manufacturing defects and installation in the first few
hours of use, and once these hours are past, it is likely to run the rest of
its life with only normal maintenance.
In conducting the test, it is important to recognize the significance of
each component malfunction encountered and to properly interpret whether the
malfunction indicates a need to extend the test period.
Ensure that each maintaining
agency receives the documents pertinent to the maintenance and operation of the
lighting units for which it is responsible.
Typically included are:
1. A copy of the plan marked to show any changes made
during the construction.
2. A copy of each certified shop drawing or catalog cut.
3. A copy of each instruction or parts manual supplied by
each manufacturer.
1. Luminaires.
a. Luminaire has the distribution, lamp, and aiming
stipulated in the Contract Documents.
b. Luminaire has been “leveled.”
2. Supports.
a. Support is the one stipulated for that location by the
Contract Documents.
b. Support is comprised of the correct components
according to the certified shop drawings.
3. Pull boxes.
a. Pull box is the size and type stipulated for that
location by the Contract Documents.
b. If supplied under plant sampling and testing program,
it has a TE‑24.
c. Drain is documented on form CA‑P‑1.
4. Conduit.
a. Conduit is the size stipulated for that location by
the Contract Documents.
b. Conduit is of the material stipulated for that
location by the Contract Documents.
c. Measure length installed.
5. Trench.
a. Location and depth is as stipulated by the Contract
Documents.
b. There are no sharp rocks in backfill adjacent to duct.
c. Backfill is placed in 4 inch (100 mm) lifts and
mechanically tamped.
d. Measure length installed.
6. Grounding electrodes.
a. Electrode is installed as stipulated for that location
by the Contract Documents.
b. Grounding conductor connected to ground rod with
exothermic weld.
c. Document ground resistance.
7. Wire and Cable.
a. Wire size and insulation is as stipulated for that
location by the Contract Documents.
b. Measure length installed.