AND PAYMENT

A.
General: Motor-control centers, as specified herein, will not be measured separately for


payment but will be paid for as part of the Contract lump sum price for Electrical Work as


indicated in the Bid Schedule of the Bid Form.

1.03
REFERENCES

A.
American Society for Testing and Materials (ASTM):



1.
ASTM A653/A653M
Specification for Steel Sheet, Zinc-Coated (Galvanized) or
Zinc-Iron Alloy-Coated (Galvannealed) by the Hot-Dip
Process



2.
ASTM B187


Specification for Copper Bar, Bus Bar, Rod and Shapes



3.
ASTM D2092

Guide for Preparation of Zinc-Coated (Galvanized) Steel









Surfaces for Painting

B.
Federal Specifications (FS):


1. FS
TT-C-490 Cleaning Methods for Ferrous Surfaces and

Pretreatments for Organic Coatings

C.
National Electrical Manufacturers Association (NEMA):



1.
NEMA ICS 2

Industrial Control and Systems Controllers, Contactors,








and Overload Relays Rated Not More Than 2000 Volts








AC or 750 Volts DC

D.
National Fire Protection Association (NFPA):



1.
NFPA 130


Standard for Fixed Guideway Transit Systems

E.
Underwriters Laboratories Inc. (UL):



1.
UL 845



Motor Control Centers

1.04
REGULATORY REQUIREMENTS
MOTOR-CONTROL CENTERS

RELEASE - R1.2
SECTION 26 24 19
BART FACILITIES STANDARDS
SAVE DATE: 8/19/2004
PAGE 2 OF 8
STANDARD SPECIFICATIONS

A.
Refer to Section 20 70 26 - Common Materials and Methods for Electrical Systems, for
requirements.

1.05
SUBMITTALS

A.
General: Refer to Section 01 33 00 - Submittal Procedures, and Section 01 33 23 - Shop
Drawings, Product Data, and Samples, for submittal requirements and procedures.

B.
Shop Drawings: Submit Shop Drawings and electrical diagrams of equipment and layouts.

C.
Product Data: Submit manufacturer's product data of manufactured materials and equipment.

D.
Operation and Maintenance Data: Submit maintenance data and operating instructions in
accordance with Section 01 78 23 - Operation and Maintenance Data, including the following
requirements:



1.
Description of the equipment and its components;



2.
Manufacturer's operating and maintenance instructions, parts list, illustrations, and
diagram of components;



3.
Recommended list of spare parts; and


4. Wiring
diagrams.

E.
Test Reports: Submit certified test reports of factory and field tests performed, verifying that
performance of equipment meets Specification requirements.

1.06
DELIVERY, STORAGE AND HANDLING

A.
Ship each unit securely wrapped, packaged, and labeled for safe handling of shipment and to
avoid damage or distortion.

B.
Store motor control centers in secure and dry storage facility.
PART 2 - PRODUCTS

2.01
MOTOR CONTROL CENTERS

A.
Provide motor control centers conforming to UL 845 and NEMA ICS 2, Class 2, Type B, rated
480 V, three-phase, three-wire, 60 Hz, totally enclosed, deadfront free-standing modular
assembly having vertical and horizontal buses, wireways, and compartments equipped with
circuit breakers and starters as indicated.

B.
Provide nameplate on each motor starter and control center in accordance with NEMA ICS 2,
showing manufacturer's name and brand designation, the referenced standard, type, class, and
rating as applicable.

C.
Motor control centers shall include the following features, appurtenances, and accessories:
MOTOR-CONTROL CENTERS

RELEASE - R1.2
SECTION 26 24 19
BART FACILITIES STANDARDS
SAVE DATE: 8/19/2004
PAGE 3 OF 8
STANDARD SPECIFICATIONS



1.
Enclosure: NEMA 1 type enclosure with drip shield, modular assembly allowing a
maximum of six size one compartment units in one vertical assembly, without structural
interference. NEMA 12 type enclosure for damp and dusty locations. Include the
following features, appurtenances, and accessories:



a.
Provide each unit compartment with individual door having concealed hinges and
unit door mechanically interlocked with unit circuit breaker to prevent opening or
closing of door when the circuit breaker is in the ON position. Provide defeater to
bypass the interlock.




b.
Equip circuit breaker in each compartment with mechanism and operating handle
for operation at front door. Handle shall be lockable at both ON and OFF
positions. Provide method so each unit can be padlocked in the test position with
the stubs completely withdrawn from the vertical buses.




c.
Provide horizontal wireway with removable coverplate at the top and bottom for
wiring between sections, incoming conduit and cable, and control wiring. Provide
top trough separated by a barrier from the main horizontal bus.




d.
Provide minimum 4-inch wide vertical wireway, with its own door, adjacent to
each vertical section and accessible front.




e.
Provide with adequate reinforced steel framework to form a rigid structure with
smooth outer surface free from burrs, ridges, and other blemishes.




f.
Provide enclosure fabricated from zinc-coated steel sheet conforming to ASTM
A653/A653M, zinc coating designation G90, minimum thickness of 14 gage.




g.
Provide painted finish for all ferrous and galvanized metal surfaces as follows:
ferrous metal surfaces shall be prepared for painting in accordance with FS TT-C-
409. Galvanized metal surfaces shall be prepared for painting in accordance with
ASTM D2092. After pretreatment, surfaces shall be prime-painted with an
approved corrosion-inhibitive metal primer for ferrous or galvanized surfaces, as
applicable. Finish coat shall be heavy-duty, industrial-grade polyurethane enamel
in color as selected by the Engineer.



2.
Horizontal and Vertical Buses: Provide main horizontal buses at the top or center of the
structure. Provide vertical buses for feeding power to each compartment in each vertical
assembly and securely bolted to the main buses. Buses shall meet the following
requirements:




a.
Bus bar shall conform to ASTM B187, 98 percent conductivity copper, tin-plated,
fully insulated by extruded sleeve or wound tape.




b.
Each horizontal and vertical bus shall be rated for a minimum of 600 A and 300 A
respectively, unless the particular section requires higher rating at vertical buses
due to the arrangement of the horizontal buses. Both vertical and horizontal buses
shall have current density not to exceed 1 kA per square inch unless otherwise
indicated.
MOTOR-CONTROL CENTERS

RELEASE - R1.2
SECTION 26 24 19
BART FACILITIES STANDARDS
SAVE DATE: 8/19/2004
PAGE 4 OF 8
STANDARD SPECIFICATIONS




c.
Each bus shall be rigidly held by bus supports that have high dielectric qualities,
are moisture-resistant, non- carbonizing, non-tracking, and have vertical creepage
surfaces to prevent faults due to build-up of conductive dirt.




d.
Both horizontal and vertical buses shall be completely isolated with bus support
molding, both between phase- to-phase and phase-to-ground. Cutouts at the
molding for plug-in unit stabs shall be equipped with shutter cover when the unit is
in the draw-out position, to avoid accidental contact with the vertical buses.




e.
Bus assembly shall be braced to withstand short-circuit rating as indicated but not
less than 42 kA symmetrical (rms).




f.
Bus connections shall be made only by means of machine screws into threaded
holes or with through-bolts with washers and nuts. Connections shall be provided
with lockwashers for mechanical locking.




3.
Ground Bus: Provide continuous bare copper ground bus, 1/4-inch by two inches in
cross-section, provided throughout the length of the control center.



4.
Compartments: Compartment arrangement shall be in accordance with the MCC
schedules and configurations indicated for the purpose of standardizing compartment
numbers at all passenger stations. Provide spaces, if any, at the lowest portion of each
section and assign a continued compartment number from the schedule.




a.
Each section shall be designed such that each compartment can be easily modified
to accommodate any standardized draw-out unit. Provide steel isolation barrier
between units with rigid connection to form an effective grounding path to the
steel structure.




b.
Provide unit guides in unit compartment for aligning starter stabs.



5.
Motor Control Center Units:




a.
Motor control center units with NEMA 4 starter and smaller shall be of the draw-
out type. Provide a positive guidance system to assure proper alignment of power
stabs in dead front openings to the vertical power bus that shall be isolated from
the starter unit.




b.
Design each section such that each unit can be easily modified to accommodate
any standardized draw-out unit. Provide steel isolation barrier between
compartments with rigid connection to form an effective grounding path to the
steel structure.




c.
Components in each draw-out unit shall be the manufacturer's standard products
and readily available for repair and maintenance.




d.
Make plug-in connections by self-aligning, silver-plated stab-type, plug-in fingers
designed to tighten onto the vertical bus during high currents.
MOTOR-CONTROL CENTERS