DEPARTMENTAL MATERIALS SPECIFICATION
ELECTRICAL SERVICES
DMS - 11080
ELECTRICAL SERVICES
EFFECTIVE DATE: JANUARY 2012
11080.1. Description. This specification governs the materials, composition, and quality of
electrical services.
11080.2. Units of Measurements. The values given in parentheses (if provided) are not
standard and may not be exact mathematical conversions. Use each system of units separately.
Combining values from the two systems may result in nonconformance with the standard.
11080.3. Material Producer List. The Traffic Operations Division (TRF) maintains the
Material Producer List (MPL) of all materials conforming to the requirements of this
specification. Electrical services appearing on the MPL, entitled “Roadway Illumination and
Electrical Supplies,” need no further sampling or testing unless deemed necessary by the Project
Engineer or TRF.
11080.4. Bidders’ and Suppliers’ Requirements. The Department will purchase or allow on
projects only those products listed by manufacturer and product code on the MPL. Use of
pre-qualified product does not relieve the contractor of the responsibility to provide products that
meets this specification. The Department may inspect or test material at any time and reject any
material that does not meet the specifications.
Notify the Department in writing of selected electrical services from the MPL intended for use
on each project. Provide evidence of Underwriters Laboratories (UL) certification to produce and
build electrical services and service enclosures.
11080.5. Pre-Qualification Procedure.
A. Pre-Qualification Request. Submit two legible copies of catalog cut sheets for all
components required for a complete electrical service, schematics, paint color samples,
and pedestal service drawings to the Texas Department of Transportation,
Traffic Operations Division, Traffic Engineering Section, 125 East 11th Street,
Austin, Texas 78701-2483.
B. Pre-Qualification Submittals. Mark catalog sheets to indicate the specific components
submitted for pre-qualification. Provide samples when directed by the Department. Follow
submittal guidelines as required by the Department.
The Traffic Operations Division, Traffic Engineering Section (TRF-TE) reviews
submittals, tests samples for specification compliance, and updates the MPL to include
materials that meet specification requirements.
Submit all materials for pre-qualification approval at no cost to the Department.
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DEPARTMENTAL MATERIALS SPECIFICATION
ELECTRICAL SERVICES
C. Disqualification. If material provided on a project does not match the pre-qualified
submittals, the material may be removed from the MPL for one year at the discretion of
the Department.
D. Requalification. If materials are removed from the MPL for failing to meet any of the
specification requirements, the producer may not submit for requalification for a period of
one year from the date of removal. TRF-TE may waive this time period, if provided with
documentation from an independent testing facility stating the materials meet all
requirements. TRF-TE will reinstate the one-year time period if, after retesting, the
material again fails any of the specification requirements.
11080.6. Material Requirements.
A. Service Enclosures.
1. General Requirements. Use new materials. Comply with the applicable provisions of
the National Electrical Code (NEC) and National Electrical Manufacturers Association
(NEMA) standards. Provide UL listed components and recognized accessories. When
reference is made to UL, it can be considered to mean a current Nationally Recognized
Testing Laboratory (NRTL) as shown on the Occupational Safety and Health
Administration (OSHA) web site. Size the electrical service entrance conduit and
conductors, disconnect, lighting contactors, load centers, panel boards, and branch
circuit breakers in accordance with the electrical service data chart on the plans.
Provide electrical service Types A, C, D, T, and pedestal services (PS) as schematically
detailed on the Electrical Detail (ED) standards. Provide other electrical service types
by special specification when shown on the plans. See the following for specific
requirements for each electrical service type:
• DMS-11081, “Electrical Services — Type A”
• DMS-11082, “Electrical Services — Type C”
• DMS-11083, “Electrical Services — Type D”
• DMS-11084, “Electrical Services — Type T”
• DMS-11085, “Electrical Services — Pedestal (PS)”
Faulty fabrication or poor workmanship in materials, equipment, or installation will be
justification for rejection. Provide manufacturer’s warranties or guarantees when
offered as a customary trade practice.
Provide stainless steel for bolts, nuts, screws, and miscellaneous hardware, unless
otherwise specified or approved.
Provide electrical conductors listed on the MPL. Install conductors in electrical services
according to the requirements of the current ED standards and Item 620 of the current
Standard Specifications.
Provide padlocks keyed with Master #2195-Type 2 for main disconnect handles,
lockable electrical enclosures, and safety switches. Provide padlocks equipped with
brass tumblers. Provide two keys for each padlock. Keys and locks will become
property of the Department.
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DEPARTMENTAL MATERIALS SPECIFICATION
ELECTRICAL SERVICES
When required by the electrical service data chart or by the electrical service provider,
provide a UL listed, heavy-duty, 600V, non-fused, NEMA type 3R enclosure safety
switch equipped with a solid neutral assembly. Provide a handle that can be field drilled
by installing contractor for padlocking switch in the ON and OFF positions.
Provide electrical service support Types TP, SF, SP, GC, and OC as detailed on the ED
sheets and as required in the plans. Provide other electrical service support type as
shown on the plans.
2. Main Circuit Breaker. Provide a thermal-magnetic main circuit breaker as required in
DMS-11081 through DMS-11083. Ensure circuit breakers meet the requirements of
UL 489 with a minimum interrupting capacity of 10,000 amperes and a voltage rating
compatible with its use as the main disconnect device. Use a breaker rated for the
voltage and amperage shown on the electrical service data chart on the plan sheets. Do
not use back-fed breakers as the main disconnect device.
3. Branch Circuit Breaker. Provide thermal-magnetic branch circuit breakers with a
minimum interrupting rating of 10,000 amps and a voltage rating compatible with their
use. Size branch circuit breakers in accordance with the electrical service data chart as
shown on plans. Provide full size circuit breakers. Do not use tandem or half-width
circuit breakers. Ensure circuit breakers meet the requirements of UL 489.
4. Enclosure.
a. General Requirements. Provide NEMA 3R enclosures. Do not allow conduit to
enter through the equipment mounting back plate. Ensure condensation will drain
from the bottom of the enclosure before leaving the factory. Provide mounting feet
for all enclosures except galvanized steel (GS) and pedestal service (PS) enclosures.
Ensure service assemblies and enclosures are UL listed for their intended purpose.
Use a UL 508A listed industrial control panel shop to build or assemble Type A and
Type C electrical service enclosures and Type D electrical service enclosures, when
an internal lighting contactor, photoelectric control, or three-position Hand-Off-Auto
(HOA) control station is required; and all auxiliary equipment enclosures mounted
with service equipment and paid for as part of Item 628, “Electrical Services.”
Except for pedestal enclosures, attach enclosure door with a continuous stainless
steel piano hinge with stainless steel pin for stainless steel enclosures; a continuous
stainless steel or aluminum piano hinge with stainless steel pin for aluminum
enclosures; two heavy duty hinges for enclosures up to 30 in. in height; or three
heavy duty hinges for enclosures over 30 in. in height. Heavy-duty hinges shall be
stainless steel and must have a 0.185 in. minimum diameter zinc electro-plated steel
pin or a stainless steel pin. Rate two point hinged doors for a minimum 56 lb. of
loading. Rate three point hinged doors for a minimum 70 lb. of loading.
Ensure all hinged enclosure doors are capable of being held open a minimum of
130 degrees, with mechanical arm or other approved means to hold the door open.
Provide door with an attached data pocket sized with minimum dimensions of 10 in.
× 11-1/2 in. constructed of either thermoplastic or metal. If pocket will not fit in
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DEPARTMENTAL MATERIALS SPECIFICATION
ELECTRICAL SERVICES
enclosure, provide pocket as large as possible, as approved by the Department.
Mechanically attach pocket with stainless steel bolts, nuts, studs, or other approved
method.
Prepare a schematic drawing specific to each individual service. Laminate the
drawing and place in the document pocket of the enclosure at the time of shipment to
the job site. Laminate the applicable wiring diagrams and complete project plan
sheet layouts for the equipment and branch circuits supplied by that service and
place in the document pocket prior to shipping. The complete set of laminated
applicable sheets may be reduced to 8-1/2 in. × 11 in.
Provide an equipment mounting panel installed inside the enclosure on collar studs
or tapped bosses, constructed of a minimum 12 gauge galvanized steel. Do not paint
equipment mounting panel. Provide dead-front trim for all service enclosures except
Type A pole mounted services.
Except for Type T and pedestal enclosures, provide a stainless steel lockable handle
controlling the door latch. For enclosure doors less than 36 in. in height, latch door at
one or more points. For enclosure doors 36 in. in height or larger, latch door at two
or more points. In all cases, meet minimum UL requirements. Supply door handle
with tumbler type lock or padlock.
b. Galvanized Steel (GS). GS enclosures will only be allowed as called for in
DMS-11082 through DMS-11084. Galvanized steel is not allowed for Types A or
for custom-built C or D enclosures.
c. Aluminum (AL). Provide AL enclosures constructed of Series 5000 aluminum with
0.08 in. minimum thickness for all enclosures except for 0.10 in. minimum thickness
for pedestal enclosures. Prime and paint the enclosure exterior only.
d. Stainless Steel (SS). Provide SS enclosures constructed of 14 gauge minimum
stainless steel for all enclosures except for 12 gauge minimum stainless steel for
pedestal enclosures. Do not paint stainless steel enclosures.
5. Auxiliary Enclosure. When separate auxiliary enclosures for HOA switch,
photoelectric control, and lighting contactors for Type D services are required and
approved by the Engineer, provide a UL Listed assembly with outer door. Mount
photoelectric control inside the auxiliary enclosure when required by descriptive code.
Auxiliary enclosures will not have an external operating handle, will not need a data
pocket, and door may latch at only one point. All auxiliary enclosures must be lockable.
For Type C auxiliary enclosures, see DMS-11082 for requirements.
6. Labels. Provide self-sticking labels suitable for outdoor use. Smaller letters than those
specified are permitted only if the standard labeling will not physically fit on the smaller
enclosures.
On shop built or shop assembled service assemblies and auxiliary equipment
enclosures, place a permanent sticker on the interior of the exterior door the enclosure
that has a unique serial numbered UL Label with the words, “LISTED ENCLOSED
INDUSTRIAL CONTROL PANEL.” On the same label or on a different label show:
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DEPARTMENTAL MATERIALS SPECIFICATION
ELECTRICAL SERVICES
the name, location, and phone number of the shop; the UL file number of the 508A
shop; the shop order or drawing number; the date of manufacture or assembly; and the
line voltage.
Label the electrical service enclosure, “SUITABLE ONLY FOR USE AS SERVICE
EQUIPMENT.” Permanently label the exterior of all pole mount electrical service
enclosure doors, “DANGER HIGH VOLTAGE.” Meet OSHA lettering style and color
requirements. Use 1 in. to 1-1/2 in. tall letters. Install “Arc Flash Hazard” label and
provide other labels as required by UL or NEC. For pedestal services, apply these labels
on the interior dead front cover. Place these labels on auxiliary enclosures unless the
enclosures are mounted in the same viewing plane as the electrical service enclosure
door.
Provide on a separate label the unique service name or number as shown on the
electrical service data chart on the plans. For pedestal services, use 1-in. tall letter
(min.), two-colored placard labels. Mechanically attach placard to service door on
pedestal services. Use 1-in. tall letter (min.), two-colored plastic labels for all other
enclosures. Identify the electrical service door with the type of load to be served (i.e.,
Lighting, Landscaping, Traffic Signals, and Traffic Management). Do not provide
“DANGER HIGH VOLTAGE” labels for safety switches unless specifically required
by the serving utility.
Label all components using two-colored plastic labels with minimum 3/16 in. tall letters
or as directed by the Department. Affix breaker labels on dead front adjacent to
breakers using the circuit designation as shown in the plans. When there is no dead
front, place labels on each individual breaker.
7. Paint and Finish. For AL enclosures, provide one of the following types of powder
coating:
• A polyester thermosetting resin, which is a zinc rich primer with a TGIC (triglycidyl
isocyanurate) powder over coating or
• A zinc-rich epoxy powder applied by electrostatic spray or fluidized bed immersion,
high temperature oven cured, high density, and low gloss.
Apply paint per manufacturer’s recommendations and ensure a minimum coating
thickness of 2.5 mils. Meet the 5A or 5B adhesion classifications of ASTM D 3359.
Ensure that finish is uniform in appearance and free of scratches, pinholes, holidays, or
other defects. Provide a manufacturer’s certification verifying that the powder coating
meets one of the two types required by this specification. Unless otherwise specified,
electrical service enclosures will be grey in color except for PS enclosures, which will
be light green in color.
8. Control Circuit. When a control circuit is required, provide a 15 amp circuit breaker to
protect the control circuit. When required, provide a 600V rated, maintained-contact,
three-position HOA control station in a NEMA Type 1 enclosure. Provide a
Hand-Off-Auto legend on the face of the control station.
9. Photoelectric Control. Provide photoelectric controls listed on the MPL, unless
otherwise shown on the plans. Provide an 1800 VA photoelectric control consisting of:
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ELECTRICAL SERVICES
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A photocell,
•
Relay or bimetallic switch mounted inside a weatherproof enclosure with a standard
3-prong twist-lock solid brass photoelectric control plug,
•
ANSI color-coded photoelectric control enclosure cover made of UV stabilized
poly-acrylic or polypropylene,
•
Clear UV stabilized acrylic window,
•
Thermosetting polymer (plastic) base with polyethylene or neoprene gasket,
•
Electronic silicon photo sensor,
•
Minimum 160 joule MOV surge protection,
•
Relay or bimetallic switch that provides instant “on” at <3 foot-candles (f.c.) or up
to a 30 second delay on at 3 f.c. and 30 second time-delay “off,”
•
Normally closed contacts that fail in the closed position,
•
Operating range of -40°F to 158°F (-40°C to + 70°C), and
•
Eight-year replacement warranty.
For enclosure-mounted photoelectric controls, provide two acrylic paned windows, or
other material approved by the Department, one on each side of the enclosure. If the
window is rectangular, ensure the dimensions are approximately 1 in. x 2 in. For a
round window, provide a minimum 1-3/4 in. diameter circle. Window must meet UL 94
requirements for flammability testing. Mount a bracket and photoelectric control
receptacle inside enclosure next to each window. Except for window side, provide 2 in.
of clearance on all sides of the photoelectric control for ease of replacement. Hold the
photoelectric control receptacle in place with at least two mounting screws on the
bracket located next to each window of the enclosure. Mount the three-prong twist-lock
photoelectric control and receptacle in position to receive light from the window closest
to the photoelectric control.
10. Lighting Contactor. When required, provide a UL listed, NEMA rated lighting
contactor. Use a two-pole or multi-pole contactor as shown on the electrical service data
chart. When 30 amp and larger contactors are required, ensure the contactor has
electrically held, silver-alloy, double-break contacts designed to control high-pressure
sodium lighting loads and is rated for the line voltage. Do not provide rail-mounted
contactors.
11. Neutral and Ground Bus. For main enclosures, provide neutral and ground busses that
are bonded to the enclosure. Provide busses with properly sized lugs for grounding and
neutral conductors, including the grounded service entrance conductor. Bond neutral
and ground bus as required by the NEC with a bonding strap or with a green bonding
screw. For auxiliary enclosures, provide a separate neutral and grounding bus.
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DEPARTMENTAL MATERIALS SPECIFICATION
ELECTRICAL SERVICES
B. Service Supports.
1. Timber Pole (TP). Provide a 30-ft. ANSI Class 5 timber pole. If utility company
requires a different height pole, meet utility requirements. Meet Item 627 material
requirements. See ED standards for additional information.
2. Steel Frame (SF) and Steel Pole (SP). Fabricate SF and SP service supports from 4-in.
square by 3/16in. thick structural steel tubing, ASTM A 500 Grade A or G, or equal.
Fabricate base plate from 3/4in. thick steel plate, ASTM A 36 or equal.
Hot-dip galvanize steel frame after fabrication in accordance with Item 445,
“Galvanizing.”
For overhead utility fed services, install an eyebolt or similar fitting to attach overhead
service drop. Meet utility company mounting hardware specifications.
Provide a minimum 6 AWG stranded copper bonding jumper between adjoining pieces
of painted steel. Terminate bonding jumper at a tapped hole with a 1/4 in. × 20 machine
bolt. Do not use sheet metal screws. Use a UL listed bonding device. Remove all
non-conductive material at contact points. Ensure all threaded bonding connections are
wrench tight.
Provide dimensional detailed shop drawings for SF service supports to project engineer
for approval and show all components to be installed on SF.
3. Granite Concrete (GC) and Other Concrete (OC). For GC service supports, use a
pre-stressed granite concrete mixture consisting of gray portland cement with exposed
pink granite aggregate suitable for direct embedment without the need for special
foundations. For OC service supports, use a concrete mixture shown on the plans or as
directed by the Department.
Ensure poles greater than 10 ft. tall have a square cross-section, with chamfered corners,
and a standard taper of 0.162 in. per ft. Ensure cross-sectional dimensions do not
deviate by more than 3/8 in. Poles less than 10 ft. may be non-tapered. The allowable
pole length tolerance is -2 in. to +3 in. The width of the bottom face of the pole as it is
cast may be less than the top face. Clean small cavities larger than 1/4 in. but smaller
than 3/4 in. diameter, and less than 3/8 in. deep. Saturate with water and fill with
mortar. Repair larger non-structural cavities and spalls. Open the side of the damaged
area on a 1:1 slope, use a mechanical grinder to thoroughly clean, and fill with a highstrength, non-shrink concrete repair material. Repair poles with other defects only upon
authorization of and using the method approved by the Department.
Burn back the end of each steel reinforcing strand, at the tip and butt of the pole, to a
minimum depth of 1/2 in. Thoroughly clean the holes left by the removal of the strand
to remove loose residue. Completely fill the holes with non-shrink grout and provide a
smooth and even surface.
Provide a minimum concrete cover of 1-1/4 in. over pre-stressing strands.
Ensure the pole straightness does not deviate more than 3/8 in. in any 10 ft. section.
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DEPARTMENTAL MATERIALS SPECIFICATION
ELECTRICAL SERVICES
Ensure the concrete mix, including all ingredients, contains 0.4 lb. per cubic yard or less
of chloride.
Ensure the compressive strength of concrete used in poles at transfer is not less than
4,000 psi and ensure a 28-day compressive strength of not less than 7,000 psi.
Comply with the latest version of the following standards:
•
Portland cement — ASTM C 105
•
Admixtures — ASTM C 494
•
Aggregates — ASTM C 33 or C 330
•
Reinforcing bars — ASTM A 615
•
Cold-drawn spiral wire — ASTM A 82
•
Prestressing strand, 270K — ASTM A 416.
Provide a 4 in. tip and 3/8 in. reinforcing strands for poles greater than 10 ft. in length.
Provide a 5 in. tip and 3/8 in. reinforcing strands for poles 10 ft. or shorter in length.
Ensure a load capacity of greater than 1,188 lb. applied 2 ft. below tip of poles.
Provide poles capable of a single point pickup, from the horizontal position, when
lifting from a point 30% of the overall length down from the tip.
Label poles by imprinting on one face. Indicate manufacturer's name, year of
manufacture, length, and name or type of pole. Locate marking approximately 4 ft.
above the ground line.
Label the pole with durable ink, paint, or cast into the pole two pickup point locations
for handling the pole in the horizontal position, and one pickup point location for use in
raising the pole to a vertical position. Ensure marks are small.
When required by the utility company for overhead services, provide poles longer than
10 ft. with a 6 AWG solid grounding conductor extending the entire length of the pole
and exiting within 6 in. from the top and bottom of the pole. Connect the bottom end of
the grounding conductor to a butt wrap or butt plate grounding device.
Ensure mounting hardware and installation details of services are in accordance with
utility company specifications.
For GC and OC service support structures for overhead utility fed services,
manufacturer will provide a 3/4 in. hole measured 12 in. ± 2 in. from the top of the pole
for eyebolt-type bracket mounting. Meet utility company mounting hardware
specifications.
See current ED standard sheets for additional information.
11080.7. Archived Versions. Archived versions are available.
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