USACE / NAVFAC / AFCESA / NASA UFGS-26 29 02.00 10 (November 2008)
-----------------------------------
Preparing Activity: USACE (CW) Superseding
UFGS-26 29 02 00 10 (April 2006)
UNIFIED FACILITIES GUIDE SPECIFICATIONS
References are in agreement with UMRL dated January 2009
SECTION 26 29 02.00 10
ELECTRIC MOTORS, 3-PHASE VERTICAL SYNCHRONOUS TYPE
11/08
NOTE: This guide specification covers the requirements for the procurement
of three-phase vertical synchronous motors, 1500 horsepower and above, for driving
storm-water pumps for local flood-control pumping stations.
Edit this guide specification for project specific requirements by adding, deleting,
or revising text. For bracketed items, choose applicable items(s) or insert
appropriate information.
Remove information and requirements not required in respective project, whether
or not brackets are present.
Comments and suggestions on this guide specification are welcome and should
be directed to the technical proponent of the specification. A listing of technical
proponents, including their organization designation and telephone number, is
on the Internet.
Recommended changes to a UFGS should be submitted as a Criteria Change Request
(CCR).
PART 1 GENERAL
NOTE: This Section covers motors with special features of construction which
are considered necessary to provide maximum insurance against failures where
the motors are to be operated only for short periods of time, at infrequent
intervals, and at locations where the average relative humidity of the air is
high. Where operating characteristics or features of motor construction are
different from those normally specified, this specification shall be modified
accordingly. The designer shall also consider unusual service conditions such
as direct exposure to the sun, vermin infestation, or high altitude.
In adapting this specification to any project, the form and phraseology will
be changed as necessary to properly specify the work contemplated. When deviations
from this specification are considered, necessary prior approval from HQUSACE
will be obtained.
Instructions for Section 22 10 00.00 10 VERTICAL PUMPS, AXIAL-FLOW AND MIXED-FLOW
IMPELLER-TYPE, specify that Section 4 of Part IV, Technical Provisions, be reserved
for insertion of the technical provisions of this guide specification.
The following should be included in section "L" of standard form 36, Information
to Bidders.
"It is preferred that the field poles be secured to the rotor structure by means
of dovetails, but an alternate method of construction will be acceptable, provided
that evidence of its adequacy, satisfactory to the Contracting Officer, is submitted
with the bid."
The designer should consider prequalifying the bidders based on past experience
with this type and size of motor. Criteria for qualifying should be included
in section "L" of standard form 36.
1.1 REFERENCES
NOTE: This paragraph is used to list the publications cited in the text of
the guide specification. The publications are referred to in the text by basic
designation only and listed in this paragraph by organization, designation,
date, and title.
Use the Reference Wizard's Check Reference feature when you add a RID outside
of the Section's Reference Article to automatically place the reference in the
Reference Article. Also use the Reference Wizard's Check Reference feature
to update the issue dates.
References not used in the text will automatically be deleted from this section
of the project specification when you choose to reconcile references in the
publish print process.
The publications listed below form a part of this specification to the extent referenced. The publications are
referred to within the text by the basic designation only.
[ASTM INTERNATIONAL (ASTM)ASTM A 123/A 123M(2008) Standard Specification for Zinc (Hot-Dip Galvanized) Coatings on Iron and Steel ProductsASTM A 153/A 153M(2005) Standard Specification for Zinc Coating (Hot-Dip) on Iron and Steel HardwareASTM B 344(2001) Standard Specification for Drawn or Rolled Nickel-Chromium and Nickel-Chromium-Iron Alloys for Electrical Heating Elements][INSTITUTE OF ELECTRICAL AND ELECTRONICS ENGINEERS (IEEE)IEEE C37.96(2000; R 2006) AC Motor ProtectionIEEE C57.13(2008) Standard Requirements for Instrument TransformersIEEE Std 115(1995; R 2002) Test Procedures for Synchronous Machines: Part I: Acceptance and Performance Testing; Part II: Test Procedures and Parameter Determination for Dynamic AnalysisIEEE Std 43(2000; R 2006) Testing Insulation Resistance of Rotating Machinery][NATIONAL ELECTRICAL MANUFACTURERS ASSOCIATION (NEMA)NEMA ICS 4(2005) Industrial Control and Systems: Terminal BlocksNEMA MG 1(2007; Errata 2008) Standard for Motors and Generators]1.2 SYSTEM DESCRIPTION
a. The work under this section includes furnishing all labor, equipment, and material and performing
all operations required to design, manufacture, assemble, factory test, prepare for shipment and storage,
and to deliver the vertical synchronous motors required to drive the flood-control pumps specified under
Section 22 10 00.00 10 VERTICAL PUMPS, AXIAL-FLOW AND MIXED-FLOW IMPELLER-TYPE. Supply these motors
complete with all accessories, spare parts, tools, and manufacturer's data and instructions as specified
herein.
NOTE: Include contract specification number where service conditions are described.
b. Insulation for the stator, rotor field, and exciter windings shall be full class "F" insulation as
defined in NEMA MG 1 paragraph 1.66 and as described herein. The insulation system shall be a combination
of materials and processes which provides high resistance to moisture, fungus, and other contaminants
as experienced by a motor in the service conditions specified herein.
c. The insulation system shall also be of a type designed and constructed to withstand severe humidity
conditions and to function properly after long periods of idleness without first drying out. All windings
and connections shall be of the sealed type as defined in NEMA MG 1 paragraph 1.27.2. Insulated windings
, unless otherwise approved, shall be completely assembled in the motor core before impregnating with
the insulating compound. The compound shall consist of 100 percent solid resin. Impregnation of the
windings with the insulating compound shall be by vacuum impregnation method followed by baking. Repeat
the procedure as often as necessary to fill in and seal over the interstices of the winding, but in no
case shall the number of dips and bakes be less than two dips and bakes when the vacuum method of impregnation
is used.
d. Process insulation to ground on the coil. Slot tubes or cells are not acceptable. The insulation
shall be of adequate thickness and breakdown strength throughout the length of the coil. Use mica in
the slot portion of adequate thickness to withstand the dielectric tests specified in paragraph FACTORY
TESTS.
1.3 SUBMITTALS
NOTE: Review submittal description (SD) definitions in Section 01 33 00 SUBMITTAL
PROCEDURES and edit the following list to reflect only the submittals required
for the project. Submittals should be kept to the minimum required for adequate
quality control.
A “G” following a submittal item indicates that the submittal requires Government
approval. Some submittals are already marked with a “G”. Only delete an existing
“G” if the submittal item is not complex and can be reviewed through the Contractor’s
Quality Control system. Only add a “G” if the submittal is sufficiently important
or complex in context of the project.
For submittals requiring Government approval on Army projects, a code of up
to three characters within the submittal tags may be used following the "G"
designation to indicate the approving authority. Codes for Army projects using
the Resident Management System (RMS) are: "AE" for Architect-Engineer; "DO"
for District Office (Engineering Division or other organization in the District
Office); "AO" for Area Office; "RO" for Resident Office; and "PO" for Project
Office. Codes following the "G" typically are not used for Navy, Air Force,
and NASA projects.
Choose the first bracketed item for Navy, Air Force and NASA projects, or choose
the second bracketed item for Army projects.
Government approval is required for submittals with a "G" designation; submittals not having a "G" designation
are for [Contractor Quality Control approval.] [information only. When used, a designation following the "G"
designation identifies the office that will review the submittal for the Government.] Submit the following in
accordance with Section 01 33 00 SUBMITTAL PROCEDURES:
SD-02 Shop Drawings
Motors[; G][; G, [_____]]
[Six] [_____] copies of equipment foundation dimensions; outline drawings for motor and rotor
set-down fixture and jacking provisions with weights, nameplate data, and details showing method
of mounting and anchoring the motor. Contracting Officer's approval shall be obtained in writing
prior to the commencement of manufacture of motors.
SD-03 Product Data
Insulated Windings[; G][; G, [_____]]
A detailed description of and specification for the manufacturing process, the materials and
the insulating compound used in insulating the windings for approval before manufacture of the
motors is commenced. If, in the opinion of the Contracting Officer, the insulation proposed
is not of the quality specified and if the methods of manufacture are not considered to be in
accordance with best modern practice, the motors will not be accepted.
Witness Test[; G][; G, [_____]]
[Six] [_____] copies of motor design (characteristic) curves or tabulated data indicating
the efficiency, current, and kilowatt input at rated voltage and 110 and 90 percent rated voltage,
all plotted or tabulated against torque or percent load as abscissas. Where values are given
in percentages all base values will be indicated.
NOTE: Use final sentence only when the pump and motor are furnished under the
same procurement.
[Six] [_____] copies of the motor torque curves plotted for the following values of voltage
at the motor terminals: [rated and 90 percent of rated voltage] [the output of a closed-transition
autotransformer type reduced-voltage starter supplied at rated and 90 percent of rated motor
voltage and connected on its [80] [65] percent tap]. [The pump torque curve shall be plotted
for starting, accelerating, and synchronizing against maximum head. Furnish computations to
demonstrate that the motor will pull into synchronism under all of the foregoing conditions.]
Motors[; G][; G, [_____]]
[Six] [_____] copies of complete descriptive specification for each type and size motor furnished,
with necessary cuts, photographs, and drawings to clearly indicate the construction of the motor,
specifications for the materials and treatments used to prevent corrosion of parts, and of bearing
construction. A complete listing of motor performance data in the form provided in NEMA MG 1
paragraph 21.50. Include with the submittal all information required for the selection of
protective and control equipment and for operational settings. Information such as, but not
limited to, normal and maximum operating temperatures for windings and bearings, V-curves, field
control and protective equipment to be mounted on the motor controller cubicle, locked-rotor
current, permissible locked-rotor time, starting times for each type of start as indicated above,
and subtransient, transient, and synchronous reactance. If duplicate equipment has not been
manufactured previously, calculations or tests shall be made as necessary and confirmed as required
by paragraph FACTORY TESTS. Contracting Officer's approval shall be obtained in writing prior
to the commencement of manufacture of motors.
Government Study
[Six] [_____] copies of the specified data.
Spare Parts
A complete list of renewal parts for the motor. The list shall accompany the instruction
manuals.
Antireverse Device[; G][; G, [_____]]
The design of the antireverse device for approval by the Contracting Officer.
SD-06 Test Reports
Factory Tests[; G][; G, [_____]]
[Six] [_____] copies of test reports recording all data, calculations, and curves for each
motor used.
SD-07 Certificates
Power Factor and Efficiency
[Six] [_____] copies of certification guaranteeing value of power factor and efficiency for
full load, 3/4 full load, and 1/2 full load.
Factory Tests
Complete Test
Check Tests
[Six] [_____] certified copies of the results of a "Complete Test" for duplicate equipment
of the respective rating and type will be accepted in lieu of the "Complete Test" specified
for equipment of the respective rating and type. No substitute will be accepted for the "Check
Test".
SD-10 Operation and Maintenance Data
Manufacturer's Data and Instructions [_____]
[Six] [_____] copies of printed and bound instructions manual for the proper installation,
erection, inspection, and maintenance of the machines furnished under this contract not later
than the date the equipment is shipped from the manufacturer's plant. Manuals shall include
complete installation, maintenance, and service instructions for the motors, lube oil system,
thrust bearings (including cooling water requirements), and other accessories. The instructions
shall include a cross-sectional drawing indicating the major component parts of the motor and
procedure for disassembly. The description in the manual for the motor shall be coordinated
with the installation erection instructions specified in Section 22 10 00.00 10 VERTICAL PUMPS,
AXIAL-FLOW AND MIXED-FLOW IMPELLER-TYPE for the pump and integrated with same for a complete
motor and pump assembly.
1.4 QUALITY ASSURANCE
1.4.1 Corrosion Prevention and Finish Painting
The equipment provided under these specifications will be subjected to severe moisture conditions and shall be
designed to render it resistant to corrosion from such exposure. The general requirements to be followed to
mitigate corrosion are specified below. Any additional special treatment or requirement considered necessary
for any individual items is specified under the respective item. However, other corrosion-resisting treatments
that are the equivalent of those specified herein may, with the approval of the Contracting Officer, be used.
1.4.1.1 Corrosion-Resisting Materials
Corrosion-resisting steel, copper, brass, bronze, copper-nickel, and nickel-copper alloys are acceptable corrosion-resisting
materials.
1.4.1.2 Corrosion-Resisting Treatments
Hot-dip galvanizing shall be in accordance with ASTM A 123/A 123M or ASTM A 153/A 153M as applicable. Other
corrosion-resisting treatments may be used if approved by the Contracting Officer.
1.4.1.3 Frames
Motor frames, end bells, covers, conduit boxes, and any other parts, if of steel, and if they will be coated
during the process of insulating the windings, shall be cleaned of rust, grease, millscale, and dirt, and then
treated and rinsed in accordance with manufacturers' standard process. If any of the above-listed parts are
not coated during the process of insulating the windings then, in addition to the above, give them two coats
of primer and then two coats of manufacturers' standard moisture-resistant coating, processed as required.
1.4.1.4 Cores
The assembled motor core shall be thoroughly cleaned and then immediately primed by applying a minimum of two
coats of a moisture-resisting and oil-resisting insulating compound. Air gap surfaces shall be given a minimum
of one coat.
1.4.1.5 Shafts
Exposed surfaces of motor shafts shall be cleaned of rust, grease, and dirt and, except for bearing surfaces,
given one coat of a zinc molybdate or equivalent primer and two coats of a moisture-proof coating, each cured
as required. Shafts of a corrosion-resisting steel may be used in lieu of the above-mentioned treatment.
1.4.1.6 Finish Painting
NOTE: If severely moist conditions exist, a separate paint system should be
specified using Section 09 97 02 PAINTING: HYDRAULIC STRUCTURES, system 21,
epoxy finish or equivalent. When such painting is specified, care must be taken
to specify a paint that will adhere to and not be injurious to the protective
painting provided under these specifications.
Finish painting of all equipment in accordance with the standard practice or recommendation of the manufacturer,
as approved by the Contracting Officer.
1.4.1.7 Fastenings and Fittings
Where practicable, all screws, bolts, nuts, pins, studs, springs, washers, and other similar fittings shall be
of corrosion-resisting material or shall be treated in an approved manner to render them resistant to corrosion.
1.4.2 Government Study
NOTE: Item d. may be used only when the pump and motor are furnished under
the same procurement.
Supply to the Government, for completion of its Motor Torque and Accelerating Time Studies (MTATS), the following
data:
a. Complete equivalent circuit data referred to the stator with friction, windage, and stray load losses.
b. Current, power factor, and torque versus speed (0-100 percent, inclusive, in 1 percent increments
up to 95 percent and 0.1 percent increments above 95 percent) and load (0-125 percent, inclusive, in
25 percent increments) as a function of line voltage (from 80 percent to 110 percent, inclusive, in 5
percent increments), for rated and 90 percent of rated voltage at starter. Only tabulated data will
be required.
c. Load inertia, Wk2 of motor rotating parts, pound-foot2.
[d. Load inertia, Wk2 of pump rotating parts (wet), pound-foot2.]
1.5 DELIVERY, STORAGE, AND HANDLING
Ship each motor in the vertical position with the rotor blocked inside the stator to prevent damage to the bearings.
Securely mount the motor on a skid or pallet of ample size. All small parts or elements shall be boxed. Perform
the skid mounting and boxing in a manner which will prevent damage or distortion to the motor during loading,
shipment, unloading, indoor storage, and subsequent handling. Provide weatherproof covers as necessary to protect
the motor during shipment. Any eyebolts, special slings, strongbacks, or other devices used in loading the equipment
at the manufacturer's plant shall be furnished for unloading and handling at the destination and shall become
the property of the Government.
1.5.1 Impact Recorder
Ship each motor with a three-way temporary impact recorder to measure magnitude and direction of longitudinal
(Y), lateral (X), and vertical (Z) impacts suffered during shipment. If the recorder indicates impacts equal
to or greater than those determined by the Contractor prior to shipment for any of the three directions specified
herein, inspect and test motor to determine extent of damage, if any, and repair or replace any damaged equipment.
1.5.2 Long Term Storage
NOTE: The designer will include this paragraph only when there is no available
Government storage. The designer should also investigate storage to be used
by the installation Contractor and the possibility of making this a requirement
under the installation contract.
Store all equipment provided under this contract for [_____] [days] [months] at no cost to the Government. The
storage site shall be subject to the approval of the Contracting Officer and shall meet the manufacturer's recommendations
for indoor storage. The equipment will be subject to periodic inspection by the Government to ensure that proper
storage conditions are maintained.
1.6 EXTRA MATERIALS
The following spare parts shall be furnished for each type and rating in addition to the assembled motors:
a. Two complete stator coils but not less than the number of coils to span one coil pitch with necessary
wedges and material for installation for one motor.
b. Two complete field coils, including necessary materials for installation.
c. One complete exciter field coil, including necessary materials for installation.
d. One complete set of bearing parts for pump motors. Each set to include:
(1) Stationary thrust bearing plate.
(2) Rotating thrust bearing plate.
(3) Upper guide bearing lining.
(4) Lower guide bearing lining.
(5) Two sets of oil rings for pump motors.
[(6) One complete set of parts necessary for replacement of antireverse device.]
PART 2 PRODUCTS
2.1 NAMEPLATES
Nameplate data shall include rated voltage, rated full-load amperes, rated horsepower, service factor, number
of phases, RPM at rated load, frequency, code letter, locked-rotor amperes, duty rating, insulation system designation,
and maximum ambient design temperature. Each motor shall have a nameplate listing motor characteristics in accordance
with NEMA MG 1 paragraph 21.61. A separate starting information nameplate shall be furnished as specified in
paragraph OPERATING CHARACTERISTICS. A starting information nameplate setting forth the starting capabilities
shall be provided on each motor in accordance with NEMA MG 1 paragraph 21.43.3. This nameplate shall also include
the minimum time at standstill and the minimum running time prior to an additional start.
2.2 GUARDS AND PROTECTIVE ENCLOSURES
All moving, energized, or other parts where accidental contact might be hazardous to personnel shall be equipped
with adequate guards, rails, or other suitable enclosures to prevent accidental contact. All lubrication fittings
shall be piped to convenient locations where they can be serviced from regularly utilized access ways without
removal of the guards or enclosures.
2.3 MOTORS
NOTE: For weak source (high thevenin source impedance), the electric utility
should be contacted to determine starting restrictions, maximum inrush, or voltage
dip limits. This is especially critical for motors over 100 hp. The designer
must then perform a motor torque and accelerating time study (MTATS) to evaluate
the motor starting torque and voltage dip requirement. The selection of a reduced
voltage starter will be based on the electric utility requirements and the motor
pump arrangement.
The motors to be supplied under these specifications shall be of the vertical [solid] [hollow] shaft type as
required by the pump manufacturer, with direct-connected brushless exciter, designed for full voltage starting,
of drip-proof construction, [complete with antireversing ratchet or backstop device], and shall conform to the
applicable requirements of NEMA MG 1, except as hereinafter specified.
2.3.1 Rating
NOTE: The local electric utility should be consulted for the expected average
and maximum values of percentage voltage unbalance, as defined in NEMA MG 1
paragraph 21.81.2, that will be present at the pumping station. If either value
exceeds 1 percent as recommended in NEMA MG 1 paragraph 21.81, the utility should
be requested to furnish their plans to improve the voltage unbalance. If they
are unable to do so, then the motor should be derated where the voltage unbalance
exceeds 1-2 percent. Voltage unbalance should never exceed 5 percent. Motor
manufacturers should be consulted for voltage unbalance limits whenever motors
have specified limits on locked-rotor currents, particularly the 500 percent
limit.
Each motor shall be wound for three-phase, 60 Hz, alternating current, and for the respective operating voltage
listed below:
PLANT PUMP PUMP SERVICE MOTOR OPERATING VOLTAGE
[_____] [_____] [_____] [_____]
[_____] [_____] [_____] [_____]
Design the motor for operation in a 40 degrees C 104 degrees F ambient temperature, and all temperature risers
shall be above this ambient temperature. The rated horsepower of the motor shall be not less than 110 percent
of the determined maximum load requirement of the pump. [Supply voltage unbalance will be [_____] percent.
The motor rated horsepower will be further derated according to NEMA MG 1 paragraph 21.81 for a voltage unbalance
above [1.5 percent] [2 percent].] Motors shall have a power factor and service factor of 1.0. The temperature
rise above the ambient temperature for continuous rated full load conditions and for the class of insulation
specified shall not exceed the values given in NEMA MG 1paragraph 21.40.
2.3.2 Operating Characteristics
2.3.2.1 Torques
NOTE: This guide specification identifies closed transition autotransformer-type
reduced voltage starters. These starters provide the most flexibility during
installation, when exact load and line characteristics are not determined, since
both input voltage and inrush current may be adjusted. This specification is
not meant to limit the selection of reduced voltage starter to only autotransformer
type. The use of wye-delta type starter may be appropriate in certain situations.
The reduced starter cost must be weighed against the increase cost in motor
designs; however each design should be evaluated for the most suitable type
starter. All reduced voltage starters will reduce the motor starting torque,
so the designer should evaluate the load characteristics to ensure that motor
torque will be sufficient under all starting conditions. If reduced-kVA starters
are required, EM 1110-2-3105 should be consulted for further guidance.
Starting and accelerating torque shall be sufficient to start the pump and accelerate it against all torques
experienced in passing to the pull-in speed under maximum head conditions and with rated excitation current and
a terminal voltage equal to [90 percent of rated value] [the output of a closed-transition autotransformer type
reduced-voltage starter supplied at 90 percent of rated voltage and connected on its [80] [65] percent tap].
The pull-in torque shall exceed that required by the pump under maximum head conditions but shall not be less
than 100 percent of motor full-load torque, with a terminal voltage equal to 90 percent of rated value. Pull-out
torque shall not be less than 150 percent of motor full-load torque for one minute minimum and with a terminal
voltage equal to 90 percent of rated value.
2.3.2.2 Locked-Rotor Current
NOTE: The objective of this specification is to limit the locked-rotor current
to a value sufficiently low to permit full-voltage starting. The motor horsepower
rating is to be a minimum of 110 percent of the maximum pump load at a service
factor of 1.0. Manufacturer's standard is to limit locked-rotor current to
600 percent of full load current. However, local utilities may have additional
limitations on inrush currents and should be consulted. Motor design will permit
some reduction in inrush current in which case 500 percent should be used.
If this is not sufficient, reduced-voltage starting should be used. The inrush
current limit should be specified whenever possible.
The locked-rotor current shall not exceed [600] [500] percent of rated nameplate full load running current.
[The locked-rotor current shall not exceed [_____] amperes at 90 percent of rated voltage during any point in
the starting cycle under worst case starting conditions. For autotransformer reduced voltage starting, the above
criteria shall apply to primary side and at any prescribed tap.]
2.3.2.3 Starting Capability
Each motor, when operating at rated voltage and frequency and on the basis of the connected pump load inertia,
Wk2, and the speed-torque characteristics of the maximum load during starting conditions as furnished by the
pump manufacturer, shall be capable of making the starts required in NEMA MG 1 paragraph 21.43.
2.3.2.4 Balance
The balance for each motor when measured in accordance with NEMA MG 1paragraph 20.53 shall not exceed the values
specified in NEMA MG 1 paragraph 21.54. Each motor's characteristics shall be such that the maximum vibration
requirements of Section 22 10 00.00 10 VERTICAL PUMPS, AXIAL-FLOW AND MIXED-FLOW IMPELLER-TYPE are met.
2.3.2.5 Noise
NOTE: The Department of Defense considers hazardous noise exposure of personnel
as equivalent to 85 dB or greater: A-weighted sound pressure level for eight
hours in any one 24-hour period. On the assumption that pumping plant operating
personnel may be exposed to noise levels approaching or exceeding that defined
by the DOD as hazardous, the motor noise limit should be specified not to exceed
85 dBA. The additional cost of providing motors meeting this requirement should
be investigated and weighed against an alternate of providing a room to isolate
these personnel from the noise exposure.
All motors shall operate at a noise level less than 85 decibels A-weighted mean sound pressure level (dBA).
Noise shall be determined in accordance with NEMA MG 1 paragraph 21.53.
2.3.2.6 Overspeed Option
NOTE: NEMA MG 1 paragraphs 12.48 and 21.45 specify that overspeeds are for
emergencies lasting no longer than one minute. Using this option will increase
costs due to requirements well beyond standard limits. Designer must do a cost
analysis before selection of this option.
Design each motor to withstand indefinitely, without injury, the maximum overspeed to which the motor will be
subjected when the pump to which it is connected is acting as hydraulic turbine under the maximum head with the
pump discharge pipe open.
2.3.2.7 [Antireverse Device
Install a self-actuated backstop device or antireversing ratchet, to prevent reverse rotation of the pump due
to loss of power or failure of the electric prime mover, as an integral part of the motor. Submit the design
of the device for approval such that its action is without intentional delay or excessive backlash. It shall
have sufficient capacity to prevent reverse rotation with a back flow through the pump due to a [_____]-foot
differential head. The device shall be precision machined and be complete with support housing and oil collector
as required. An oil reservoir, independent of the one used for the thrust bearing, complete with oil-level gauge
and 120-volt ac rated high and low level contacts shall be provided for the backstop device. The lubricant for
the antireverse device shall contain a corrosion inhibitor, whose type and grade shall be shown on a special
nameplate attached to the frame of the motor adjacent to the lubricating filling device.]
2.3.2.8 [Power Factor and Efficiency
NOTE: List power factor and efficiency for each size only if high efficiency
motors are required. Generally manufacturers' standards will be used.
The power factor and efficiency at full load, 3/4 full load, and 1/2 full load shall be not less than [_____],
[_____], [_____] and [_____], [_____], [_____], respectively. Motors will be rejected if factory tests specified
in paragraph FACTORY TESTS do not demonstrate that these values will be met or exceeded.]
2.3.3 Frames and Brackets
Frames and end brackets shall be of cast iron, cast steel, or welded steel. The mounting ring, unless otherwise
approved, shall be built integral with the frame or lower end bracket. Coordinate the motor installation with
the mounting arrangement specified in Section 22 10 00.00 10 VERTICAL PUMPS: AXIAL-FLOW AND MIXED-FLOW IMPELLER-TYPE,
paragraph BASE PLATE AND SUPPORTS. Furnish all equipment and materials required to mount the motor, such as
a base or pedestal, sole plates, and bolts or dowels. Install sufficient bolts and dowels to prevent any possible
movement of the motor assembly when the motor is subjected to stresses resulting from the most severe short-circuit
conditions. Treatment against corrosion shall be as specified in paragraph GENERAL REQUIREMENTS.
2.3.3.1 Stator Frame
The stator frame shall be rigid and sufficiently strong to support the weight of the upper bearing bracket load,
the weight of the stator core and windings, and to sustain the operating torques without perceptible distortion.
2.3.3.2 Supporting Brackets
The upper bracket supporting the thrust bearing and upper guide bearings shall have sufficient strength and rigidity
to support the weight of the entire rotating element of the motor, together with the pump impeller and shaft,
and the unbalanced hydraulic thrust of the pump impeller. The lower bracket supporting the lower guide bearing
shall preferably be so designed and constructed that the entire rotor can be lifted out as a unit without disturbing
the bearing alignment. If it is not feasible to construct the rotor so that it can be lifted out as a unit,
then the lower bracket shall be supported on separate base plates or structure and shall be designed so that
it can be removed through the stator. The maximum deflection of the thrust bearing support system at any point
shall not exceed the limits set by the pump manufacturer to maintain proper clearances for any operating condition.
2.3.3.3 Eyebolts
Provide eyebolts, lugs, or other approved means for assembling, dismantling, and removing the motors from above,
utilizing the overhead pumping station building crane. Furnish with the motor all lifting devices for use in
conjunction with the building crane.
2.3.3.4 Platforms and Stairways
Furnish each motor with a platform and stairway complete with railing. An easily removed section of railing
shall be provided so that the rotor shaft does not have to be hoisted above the railing when the rotor is removed.
The platform shall also provide maintenance access as required by the motor furnished. Locate the stairway [_____]
degrees [counter-] clockwise from the discharge elbow of the pump, when looking down on the motor/pump assembly.
2.3.4 Insulation Against Stray Currents
The motor shall be adequately insulated against stray currents which may be set up by the field of the motor
and which might cause injury to the motor or pump bearings. This insulation shall be arranged to break the possible
path of such currents in not less than two places in series.
2.3.5 Motor Cooling
Provide the motor with an open-type system of ventilation, taking cooling air from above the operating floor
level and discharging the heated air into the operating room through upper openings in the stator frame. The
circulation of air shall be induced by means of the fan action of the rotor. No openings to the air space below
the operating level are to be used in the motor design for ventilation or other uses that are not reasonably
airtight.
2.3.6 Stator
2.3.6.1 Stator Core
The cores shall be built up of separately punched thin laminations of low-hysteresis loss, nonaging, annealed,
electrical silicon steel; assembled under heavy pressure; and clamped in such a manner as to ensure that the
assembled core is tight at the top of the teeth of the laminated core. Laminations shall be properly insulated
from each other. Only laminations free from burrs shall be used, and care shall be taken to remove all burrs
or projecting laminations from the slots of the assembled cores. Cores shall be keyed, dovetailed, or otherwise
secured to the shaft or frame in an approved manner. Treatment against corrosion shall be as specified in paragraph
GENERAL REQUIREMENTS.
2.3.6.2 Stator Coils
The coils shall be thoroughly insulated and treated with a moisture and fungus-resisting compound in such a way
that air will be excluded and the insulation will be protected from the absorption of moisture. Provide additional
insulation for those portions of each coil which are within the slots. The coils shall fit the slots accurately
and they shall be form wound and interchangeable. The end turns shall be so designed and supported that they
will not be distorted under the most severe short-circuit conditions to which the motor may be subjected.
2.3.6.3 Insulated Stator Windings
The stator windings shall be insulated as specified in paragraph GENERAL REQUIREMENTS. Coils shall be of such
uniformity that the stator windings of all similarly rated motors will be alike, in shape and size, and interchangeable.
The stator winding and end turn connections shall be fully braced to withstand repeated full voltage starts.
The bracing system shall essentially eliminate coil vibration under these high current conditions as well as
during normal operation. A tieless bracing system will be acceptable. If a tied system is used it shall be
such that no tie depends upon the integrity of any other tie within the system.
2.3.6.4 Temperature Detectors
Six standard copper resistance-type temperature detectors, with a resistance of 10 ohms at 25 degrees C 75 degrees
F, shall be provided in the stator in accordance with NEMA MG 1 paragraph 20.63. Detectors shall be wired in
accordance with paragraph ACCESSORY WIRING AND BOXES.
2.3.6.5 Grounding
The stator frame shall have provisions for solidly grounding to the station ground system which will be furnished
and installed by others.
2.3.7 Rotor
The rotor shall be built in accordance with the best modern practice and in such a manner as to secure adequate
strength for the operating conditions described herein. The pole pieces shall be built up of thin steel laminations
accurately aligned and securely riveted or bolted together. It is preferred that the field poles be secured
to the rotor structure by means of dovetails, but an alternate method of construction will be acceptable, provided
that evidence of its adequacy, satisfactory to the Contracting Officer, is submitted with the bid.
2.3.7.1 Field Windings
The field windings shall be insulated as specified in paragraph GENERAL REQUIREMENTS. The field coils shall
be adequately insulated between turns and from the pole pieces and shall be thoroughly braced to withstand the
stresses which could be imposed under maximum pump speed.
2.3.7.2 Starting Windings
Design the starting windings for full-voltage starting, securely built into the field poles and designed to ensure
conservative stresses when the unit is operating at maximum pump speed. The bars shall be silver soldered or
brazed to heavy end segments to form a low-resistance joint of high mechanical strength. Design the starting
windings to permit any pole or group of poles to be removed.
2.3.8 Exciter
Provide each synchronous motor with a direct connected exciter without brushes, commutators, or additional bearings.
The exciter shall be capable of supplying continuously, and without overheating, the excitation for the motor
to which it is connected when the latter is operating at rated power factor, voltage, frequency, and horsepower.
Accomplish the field-protective function and the field switching and application function by semiconductor elements
mounted on suitable heat sinks supported on the motor rotor and ventilated by rotation of the rotor. The exciter
shall be either built into or so arranged that it is ventilated from the main motor enclosure. The enclosure
of the exciter shall be of drip-proof construction comparable to that of the motor. The control system shall
apply excitation to the motor field at the speed and phase angle required to obtain maximum pull-in torque.
Insulate the exciter windings as specified in paragraph GENERAL REQUIREMENTS. The field coils shall be adequately
insulated between turns and from the pole pieces and shall be thoroughly braced to withstand the stresses which
could be imposed under maximum pump speed.
2.3.9 Shaft
NOTE: Use hollow shaft pumps whenever possible, since they are more readily
adjusted. Pumps requiring large motors (above 1,000 hp) are limited by the
available motors. Investigate the exact motor capabilities and sources of supply
when using hollow shafts with motors above 1,000 hp. Solid shafts will be used
only when the available motor designs require their use.
Make the motor shaft of high grade steel, finished all over, and of ample size to drive the pump under maximum
load conditions. The shaft shall be of the [solid type and shall be connected to the pump shaft with a rigid
adjustable coupling.] [hollow type and shall be connected to the pump shaft above the thrust bearing in a manner
that will permit the pump impeller to be adjusted vertically]. Coordinate the connection with the pump shaft
and furnish a motor shaft with all provisions, fittings, and devices required to conform to the shafting arrangement
specified in Section 22 10 00.00 10 VERTICAL PUMPS, AXIAL-FLOW AND MIXED-FLOW IMPELLER-TYPE, paragraph SHAFTS.
See paragraph GENERAL REQUIREMENTS for treatment against corrosion.
2.3.10 Bearings
2.3.10.1 Thrust Bearings
Provide thrust bearings of the spring type located above the rotor. A design in which each pivot shoe rests
upon a support of metal which may take a permanent deformation in order to equalize the load on the bearing shoes,
or in which individual shoe pivots are supported on spring plates or spring disks, is not considered to be of
the self-equalizing type and will not be acceptable. The stationary shoes shall be babbitt-lined. The thrust
bearing shall have ample capacity to support the maximum pump hydraulic thrust load plus the static load while
operating under maximum rated pump conditions. The thrust bearing shall be capable of withstanding without injury
the pump being started normally without prior jacking of the rotor. The thrust bearing shall have a removable
runner and shall be arranged to permit adjustments, dismantling, and assembly of the runner and shoes without
disturbing the stator or rotor, other than jacking the load from the bearing. A spacer plate between the thrust
bearing runner plate and the thrust block will not be permitted.
2.3.10.2 Guide Bearings
Except as permitted below, provide the motor with two guide bearings, one located above the rotor and the other
below the rotor. The guide bearings shall be capable of withstanding all stresses incident to the normal operation
of the unit [and to the maximum runaway speed]. Both guide bearings shall be self-cooled, of the oil-immersed,
self-oiling type, and adequate provision shall be made for preventing oil or oil vapor from entering the motor
cooling system. The guide bearings shall be of the split-sleeve type and shall be designed and constructed so
that they can be dismantled without disturbing the thrust bearing or the motor rotor. If desired, the Contractor
may combine the thrust bearing and the upper guide bearing into a combination integral guide and thrust bearing
assembly in a common housing. In such a combination bearing, the vertical side of the thrust-bearing block,
but not the runner plate, shall be used as the journal surface.
2.3.10.3 Lubrication
Use lubricating oil containing a corrosion inhibitor. Type and grade of lubricant used shall be shown on a special
nameplate which shall be attached to the frame of the motor adjacent to the bearing filling device. In addition
to the quantity of lubricant required to initially fill the system, furnish spare lubricant in sufficient quantity
to purge and refill the system. Each lubrication system shall include oil reservoirs, oil-level sight gauge,
oil piping, valves, and necessary appurtenances.
2.3.10.4 Housing
Bearing housing shall be of a design and method of assembly that will permit ready removal of the bearings, and
prevent escape of lubricant and entrance of foreign matter. The bearings shall be protected by the lubricant
when the motor is idle. Provide suitable means to apply and drain the lubricant.
2.3.10.5 Cooling
Each thrust bearing shall be self-cooling whenever possible. When required by motor speed or load, provide an
oil cooler with suitable coils of corrosion-resisting metal in the oil reservoir of sufficient capacity to maintain
the oil at the proper temperature with [30 percent glycol] cooling water entering the coils at a temperature
of [30] [_____] degrees C and with a minimum pressure of 40 pounds per square inch. Design the cooler for safe
operation at a maximum working pressure of 345 kPa 50 psi and shall be subjected at the factory to a hydrostatic
test pressure of 517 kPa 75 psi for a period of one hour without leakage. Cooling water will be supplied by
a central system, furnished by others, consisting of a radiator, circulating water pump, and piping system terminating
at the exterior of each motor. If required an auxiliary-motor-driven circulating oil pump, rated at 480 volts,
three-phase, with electrical leads terminated in a special terminal box on the motor, and an oil pressure sensing
device shall be included in the bearing oil cooler system. Construct the cooler system so that the thrust bearing
can be readily inspected or removed for repairs. Include a water flow indicator with adjustable alarm contacts
in the water supply line. The oil reservoir shall have an oil-level gauge with high and low level normally open
contacts rated 120 volts ac.
2.3.10.6 Temperature Detectors
Provide a standard copper resistance-type temperature detector, with a resistance of 10 ohms at 25 degrees C
75 degrees F, for each bearing. Casings shall be made of copper. Detectors shall be wired in accordance with
paragraph ACCESSORY WIRING AND BOXES.
2.4 INSTRUMENTS AND GAUGES
Furnish the following instruments and gauges.
2.4.1 Thermometers
Indicating thermometers, 150 mm 6 inch vapor-tension [dial-type] [digital], with adjustable ungrounded alarm
contacts suitable for 120 volts ac shall be provided for (a) the thrust bearing, (b) the thrust bearing oil reservoir,
and (c) each guide bearing. The bulbs shall be located so as to indicate the temperatures of the hottest parts.
The thermometers shall be mounted on a thermometer panel and located on the motor housing at a location approved
by the Contracting Officer. Provide adequate length of tubing with each thermometer. The bulb and tubing shall
be insulated where necessary to prevent bearing currents. [The dial-type thermometers shall be of the [round][square]
semiflush type with black cases, white dials, and black figures and pointers.] [The digital thermometers shall
be square, semiflush type with black cases and minimum 25 mm 1 inch high display.]
2.4.2 Temperature Relay
Provide a pneumatic bearing temperature relay having two sets of electrically independent contacts, located close
to the babbitt of the thrust bearing [and each guide bearing]. Each relay shall close its contacts when the
bearing temperature reaches approximately 105 degrees C 220 degrees F. The contacts shall have a current-carrying
capacity of not less than 10 amperes, shall be ungrounded, and shall be suitable for 120 volts ac. The relays
shall be mounted in an approved accessible location and the leads brought to a terminal block mounted on the
stator frames in an approved location. The bulbs for the temperature relays shall be easily accessible and constructed
for removal and testing without disturbing the bearing or bearing housing. The tubing shall be insulated where
necessary to prevent bearing currents.
2.4.3 Oil-Level Gauge
Provide an oil-level gauge for each oil reservoir, with scale of sufficient length to indicate the oil level
at all room and operating temperatures. The gauges shall be located near the reservoirs in an approved, accessible
location where they can be easily read. Each oil-level gauge shall have adjustable high and low oil-level ungrounded
alarm contacts suitable for 120 volts ac.
2.5 PIPING
Design and furnish all piping systems within the motor for bearings, including valves and fittings. Bring these
connections out to approved positions at the bottom of the stator frame. All piping shall be clean inside and
where ending in open connections for other work, ends shall be capped for protection. Valves and other operating
devices shall be easily accessible, and gauges and indicating devices shall be mounted on a control panel as
approved by the Contracting Officer. Piping and fittings shall be of copper or brass as required. Valves shall
have bronze seats and stems and shall be suitable for the service intended. At all points where the piping system
must be disconnected for dismantling operations, provide bolted flange connections or unions. Arrangement of
piping and location of valves and joints shall be such that there will be a minimum of disturbance to piping
or interference with other service when the motor is dismantled or parts are removed for inspection or repairs.
2.6 WINDING SPACE HEATERS
NOTE: The inclusion or omission of "Winding Space Heaters" will depend upon
the decision reached after giving due consideration to the problem of prevention
of moisture condensation on the station equipment.
Install heaters in the lower section of the frame or wrap them around the winding end turns. They shall be designed
for operation on 120 volts, single-phase, 60-Hz, alternating current and of sufficient capacity or wattage that,
when energized, they will hold the temperature of the motor windings approximately 10 degrees C above the ambient
temperature. Heaters shall be de-energized when motor is operating.
2.6.1 Construction
The heaters, except for wrap-around type, shall be of the tubular type, constructed with a chrome-nickel heating
element embedded in a refractory insulating material, and encased in an approved watertight metal sheath. They
shall be designed for continuous operation and have a maximum watt density of 20 watts per square inch. The
rate of heat dissipation shall be uniform throughout the effective length of the heater. Cartridge-type heaters
of equivalent construction, as approved by the Contracting Officer, will be acceptable. Heaters installed around
the winding end turns shall consist of the required turns of heating cable wrapped around the end turns and secured
in place before the winding is impregnated.
2.6.2 Element
Heating element shall conform to the requirements of ASTM B 344 for an 80 percent nickel and 20 percent chromium
alloy.
2.6.3 Sheath
Sheath shall be of a corrosion-resisting, nonoxidizing metal and shall have a wall thickness not less than 0.625
mm 0.025 inch.
2.6.4 Insulation
Insulation shall be a granular mineral refractory material, highly resistant to heat, and shall have a minimum
specific resistance of 1,000 megohms per inch cubed at 585 degrees C 1,000 degrees F. Insulation for the heating
cable (winding wrap-around type heaters) shall be suitable for a conductor temperature of 180 degrees C 356 degrees
F.
2.6.5 Terminals
Terminals of the heater, including the leads, shall be watertight and shall be provided with leads suitable for
making connections to a separate drip-proof terminal box located on the motor frame. The terminal box shall
be readily accessible through the crating, so that winding heaters can be energized while motors are in storage.
2.7 MAIN LEADS AND TERMINAL BOX
2.7.1 Stator Terminals
Insulated terminal leads shall receive a treatment equal to that of the motor winding. Six leads shall be brought
out of the stator frame and connections shall be made as required for the current transformers in paragraph ACCESSORY
WIRING AND BOXES. Provide terminal lugs for connection to the motor shielded single-conductor supply wiring.
2.7.2 Stator Terminal Box
Drip-proof cast iron or steel terminal boxes, treated in the same manner specified for frames to resist corrosion,
shall be supplied for housing the stator lead connections, surge capacitors, surge arresters, and current transformers
and shall have adequate space to facilitate the installation and maintenance of cables and equipment. Boxes
shall have a [bolted] [hinged lockable] cover providing unrestricted access, be mounted on the motor frame, and
shall have an auxiliary floor supporting structure, when required, supplied by the motor manufacturer. Conduit
entrance shall be from the bottom. The boxes shall be designed to permit removal of the motor supply leads when
the motor is removed. Provide a "HIGH VOLTAGE [_____] VOLTS" warning sign on the cover of the box. When looking
down on the motor/pump assembly, the terminal box shall be located between [_____] degrees and [_____] degrees
[counter-] clockwise from the discharge elbow of the pump. A ground bus and means for external connection to
the station grounding system shall be provided in the stator terminal box.
2.8 SURGE PROTECTION
NOTE: To obtain the most reliable protection for 2,300- and 4000-volt motors,
surge capacitors and arresters, mounted at the motor terminals, should be specified.
In addition, it is recommended that station-type arresters be installed on the
line side of the supply transformers.
2.8.1 Surge Capacitors
Furnish and install, in the main terminal box, a three-pole capacitor unit equipped with built-in discharge resistors
and using a non-polychlorinated biphenyl (non-PCB) insulating medium. Each pole shall be rated 0.5 microfarad
and [2,400] [4,160] volts line-to-line. Provide removable bus links for motor testing. These links shall be
treated to resist corrosion, shall be designed to maintain a positive contact, and shall have low contact resistance.
2.8.2 Surge Arresters
NOTE: Use 3,000 MCOV arresters for 2,400-volt systems or effectively grounded
4,160-volt systems. Use 4,500-MCOV for ungrounded or resistance grounded 4,160-volt
systems.
Surge arresters of the station type with porcelain tops shall be furnished and installed in the main terminal
box. The arresters shall be of the metal-oxide type rated [3,000] [4,500] [_____] maximum continuous operating
voltage line-to-ground. Provide removable bus links for motor testing. These links shall be treated to resist
corrosion, shall be designed to maintain a positive contact, and shall have low contact resistance.
2.8.3 Space Heater
If recommended by the surge protection manufacturer, furnish a space heater of adequate capacity, rated 120 volts
and install it in the terminal box. Space heater maximum watt density shall not exceed 20 watts per square inch.
2.9 CURRENT TRANSFORMERS
NOTE: For motor differential protection, the "Flux-Balancing Current Differential"
scheme, as shown in Fig. 16 of IEEE C37.96, is preferred and will generally
be applicable. In this case, the window-type current transformers should be
used. However, when the KVA rating of a motor is approximately one-half the
supply transformer KVA rating, or greater, it may be necessary to use the differential
scheme shown in Fig. 15 of IEEE C37.96, in which case the "Differential Protection"
scheme should be used.
Current transformer shall meet the applicable requirements of IEEE C57.13 and IEEE C37.96. Secondary circuits
[shall] [shall not] be grounded at the motor, and all leads from each individual transformer shall be brought
out to terminal blocks. They shall be of the dry or compound-insulated type and shall be provided with a suitable
means of mounting and for grounding the frame. Each current transformer secondary lead shall be connected to
a terminal block of the short-circuiting type and shall be conveniently located to permit short-circuiting the
secondary windings without requiring access to the primary bus compartments. The polarity of the current transformers
shall be plainly marked. [Each motor shall be provided with three indoor dry-type window transformers with single
secondary and rated [50/5 amperes, 600 volts] [_____]. Current transformers shall have minimum full-wave insulation
level of 10 kV and, when installed, shall meet the requirements for a [60 kV] [_____] basic impulse level (BIL).
The transformers shall be mounted in the main terminal box and shall be arranged in the "flux-balancing" connection.]
[Each motor shall be provided with three current transformers of rated [4,160] [_____] and [60 kV] [_____] basic
impulse level (BIL). The transformers shall be mounted in the main terminal box and shall be connected in the
wye point of the winding for use with differential relays.] All current transformers shall be suitable for continuous
operation at the full-rated voltage and current at a frequency of 60 Hz. All current transformers shall be designed
to withstand, without damage, the thermal and mechanical stresses resulting from short-circuit currents corresponding
to ratings of the breakers in the circuits to which they are connected.
2.10 ACCESSORY WIRING AND BOXES
Except for current transformer leads and field control leads, all accessory wiring shall terminate in an accessory
terminal box, unless otherwise approved by the Contracting Officer. Boxes shall be drip-proof and treated in
the same manner specified for frames to resist corrosion. The accessory terminal box shall be furnished with
a door hinged full length and shall be mounted on the motor in a location approved by the Contracting Officer.
Rigid galvanized steel conduit shall be used wherever practicable and shall be arranged to make removal unnecessary
when the motor is dismantled. A wiring diagram within the enclosure shall be provided for all circuits and each
conductor shall be identified with the designation shown on the diagram. All wiring shall terminate on terminal
blocks as specified below.
2.10.1 Wiring
Except as otherwise approved, all wiring shall be 125 degrees C rated flexible copper conductors, No. 14 AWG
minimum, with 600-volt insulation. The size and type of temperature detector leads may be in accordance with
the manufacturer's standard practice and, where required, shall be suitable for contact with lubricating oil.
Each detector shall be connected by three leads to terminal blocks, with one wire connected to a common point
on the blocks. The common point for the stator detectors shall be separate from that for the bearing detectors.
2.10.2 Terminal Blocks
All terminal blocks shall be molded closed-back type as defined in NEMA ICS 4, rated not less than 600 volts
and shall be provided with covers. The terminals shall be screw-clamp type or stud-and-nut type. White or other
light-colored marking strips, fastened by screws to the molded sections at each block, shall be provided for
circuit designation. Each connected terminal of each block shall have the circuit designation or wire number
permanently marked on a strip. Reversible or spare marking strips shall be furnished with each block and at
least 10 percent spare terminals shall be provided.
2.11 JACKING PROVISIONS
Provide suitable means for hydraulic jacking of the rotor to permit inspection, adjustment, or removal of the
thrust bearing. Provisions shall also be made for blocking the rotor in the fully raised position. The blocking
device shall not require maintenance of hydraulic pressure on the jacks while the assembly is in the raised position.
2.12 SPECIAL TOOLS AND EQUIPMENT
Provide special tools, jigs, fixtures, lifting tackle, and instruments which may be necessary in assembly, erection,
operation, maintenance, and repair of equipment. Special tools and equipment are those the design, purpose,
and use of which are peculiar to equipment furnished and which are not available from normal wholesale or retail
outlets. The motor manufacturer shall provide hydraulic jacking devices as required in order to pull the thrust
bearing thrust collar from the upper end of the shaft and shall also furnish one complete set of lifting attachments
such as detachable eyebolts or special slings for handling various parts with a hoist.
2.13 SET-DOWN FIXTURES
Furnish one separate motor set-down fixture for each motor rating supplied. This fixture, when installed on
the operating floor, shall provide sufficient clearance above the floor for the motor shaft and coupling extending
below the motor frame. The fixture shall be suitable for holding the motor during assembly and disassembly.
Furnish one separate rotor set-down fixture for each motor rating supplied. The fixture shall hold the rotor
in the horizontal position above the floor without unduly stressing the rotor pole pieces or laminations. The
motor and rotor fixtures shall be shipped to the pumping station prior to the shipment of any motor.
2.14 FACTORY TESTS
NOTE: The designer should carefully consider whether to allow the Contracting
Officer to waive these tests. Decision should be based on expertise in the
field within the Division or District.
Give one motor of each rating and type, selected at random by the Contracting Officer, a complete test. The
remainder of the motors shall be given a check test. All complete tests shall be [witnessed by the Contracting
Officer] [waived in writing].
2.14.1 Witness Test
When the Contractor is satisfied that a motor selected for a "Complete Test" performs in accordance with the
requirements of the specifications, the Contracting Officer shall be notified and shall be furnished with two
copies of the tabulated data, calculations, and curves required by paragraph COMPLETE TEST below or required
to confirm the data required in paragraph SUBMITTALS. Three weeks will be required, after receipt, to review
the foregoing information. Should the witness test indicate that a motor does not perform in accordance with
the requirements of the specifications, changes or corrections shall be made and new complete witness tests run,
at no additional cost to the Government.
2.14.2 Complete Test
NOTE: For the large motors (1,500 hp and above), the efficiency is high, i.e.
95 percent at 1/2 to full load, however, efficiency varies with motor design.
In general, high efficiency motors are not cost effective in the large size
motors covered by this specification. If other than manufacturer's standard
efficiency is required, the designer should list those values in paragraph FACTORY
TEST.
A complete test of a synchronous motor shall including the following:
a. Resistance of armature and field windings.
b. Polarity of field coils.
c. High-potential tests of armature and field windings in accordance with NEMA MG 1 paragraph 21.52.
d. Air gap measurement.
e. V-curves (for zero, 1/2, 3/4, and full load).
f. Determination of the subtransient, transient, and synchronous reactance.
g. Conventional efficiency tests, in accordance with NEMA MG 1paragraph 21.44. Motor shall meet manufacturer's
published efficiency criteria for 1/2, 3/4, and full rated loads. Calculation of efficiency shall include
[that portion of the thrust bearing loss produced by the motor itself] [bearing loss due to external
thrust load].
h. Tests to determine temperature rise in accordance with NEMA MG 1 paragraph 21.40.
i. Insulation resistance-temperature test, in accordance with IEEE Std 43. Test result values shall
be plotted on semilogarithmic graphs, the insulation resistance values as logarithmic ordinates and the
temperature values as uniform abscissas. Readings shall be taken at approximately 10 degrees C intervals.
Temperature shall be determined by the resistance method. Also, for comparison purposes, a curve indicating
the safe operating value of insulation resistance shall be plotted on the same sheet.
j. Noise level tests in accordance with NEMA MG 1 paragraph 20-50.
k. Motor balance in accordance with NEMA MG 1 paragraph 20.54.
l. Conformance test in accordance with NEMA MG 1 paragraph 20.49.
m. Torques. Torque tests shall be performed in accordance with IEEE Std 115 to demonstrate that the
values specified in paragraph "Torques," will be met or exceeded.
2.14.3 Check Tests
A check test of a synchronous motor and exciter shall include the following:
a. Routine test in accordance with NEMA MG 1 paragraph 21.51.
b. Cold resistance measurement.
c. Insulation resistance and winding temperature at time the insulation resistance was measured.
d. Conformance test in accordance with NEMA MG 1 paragraph 20.49.
e. Motor balance in accordance with NEMA MG 1 paragraph 20.54.
2.14.4 Stator Winding Coil Tests
All coils, either before or after they are placed in the slots, shall be tested for short circuits between turns
of the individual coils by applying a high frequency voltage of not less than 75 percent of the voltage for which
the machine is insulated, or by applying a surge test voltage of equivalent value to the terminals of each coil.
Equivalent surge voltage shall be a wave whose peak value is equal to 1.06 times the voltage for which the motor
is insulated.
2.14.5 Space Heater Tests
Each winding space heater unit shall be tested at the factory for successful operation and dielectric strength.
PART 3 EXECUTION (Not Applicable)