SECTION 16340 Medium Voltage Switching and Protection Assemblies Rev 0

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SECTION 16340:

GUIDELINE SPECIFICATION FORMEDIUM VOLTAGE SWITCHING AND PROTECTION

ASSEMBLIES

0 31/01/06 I IssuedforUse ~-~REV DATE DESCRIPTION PREPARED BY RC APPROVED

KINGDOMOFSAUDIARABIA

RoyalCommissionlorJubail&Yanbu

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SECTION 16340 MEDIUM VOLTAGE SWITCHING AND PROTECTION ASSEMBLIES

Rev 0 i Contract No:

TABLE OF CONTENTS

Item No Title Page No

PART 1 GENERAL...............................................................................................................1

1.01 DESCRIPTION OF WORK ..................................................................................1

1.02 SECTION INCLUDES..........................................................................................1

1.03 RELATED SECTIONS .........................................................................................1

1.04 REFERENCES.....................................................................................................1

1.05 DEFINITIONS.......................................................................................................3

1.06 SUBMITTALS.......................................................................................................4

1.07 QUALITY CONTROL ...........................................................................................5

1.08 HEALTH AND SAFETY CONSIDERATIONS......................................................5

1.09 FACTORY TESTING ...........................................................................................6

1.10 SERVICE CONDITIONS......................................................................................6

1.11 ENCLOSURES ....................................................................................................7

1.12 DELIVERY, STORAGE AND HANDLING ...........................................................7

PART 2 PRODUCTS ............................................................................................................9

2.01 GENERAL ............................................................................................................9

2.02 MEDIUM VOLTAGE SWITCHGEAR .................................................................10

2.03 MEDIUM VOLTAGE ENCLOSED BUS .............................................................23

2.04 MEDIUM VOLTAGE MOTOR CONTROLLERS................................................25

PART 3 EXECUTION .........................................................................................................33

3.01 GENERAL ..........................................................................................................33

3.02 INSTALLATION OF EQUIPMENT .....................................................................33

3.03 TESTING AND COMMISSIONING....................................................................34


Rev 0 1 of 36 Contract No:

PART 1 GENERAL

1.01 DESCRIPTION OF WORK

A. This Section specifies minimum technical requirements for supplying, installing, storing, handling, testing and commissioning of Medium Voltage Switchgear, Medium Voltage Enclosed Bus and Medium Voltage Motor Controllers as specified and shown on the Contract Drawings/Documents.

1.02 SECTION INCLUDES

A. Medium Voltage Switchgear

B. Medium Voltage Enclosed Bus

C. Medium Voltage Motor Controllers

1.03 RELATED SECTIONS

A. Section 01320 Construction Progress Documentation

B. Section 01330 Submittal Procedures

C. Section 01410 Regulatory Requirements

D. Section 01450 Quality Control

E. Section 01650 Product Delivery Requirements

F. Section 01660 Product Storage and Handling Requirements

G. Section 16055 General Provision of Low Voltage Electrical Works

H. Section 16060 Grounding and Bonding

I. Section 16120 Conductors and Cables

1.04 REFERENCES

A. The referred codes and standards are intended to provide an acceptable level of quality for materials and products. In case of conflict between these standards and the text of this Specification, the Specification text shall govern.

B. The latest revision of the referred codes and standards shall be used wherever applicable. In case of conflict, the Contractor shall propose equipment conforming to one group of codes and standards.

C. SEC-ERB Saudi Electricity Company Eastern Region Branch

1. 01-SMSS-01 General Requirements for All Equipment/Materials



2. 24-SMSS-1 Metal Enclosed Bus Duct

3. 32-SMSS-1 Medium Voltage Switchgear

D. ANSI American National Standard Institute

1. ANSI/IEEE C37.12 Guide to Specifications for AC High Voltage Circuit Breaker Rated on a Symmetrical Basis and Total Current Basis

2. ANSI/IEEE C37.32 Schedules of Preferred Ratings, Manufacturing, Specifications and Application Guide for High Voltage Air Switches, Bus Supports and Switch Accessories

3. ANSI/IEEE C37.53.1 High Voltage Current Limiting Motor Starter Fuses Conformance Test Procedures

4. ANSI C84.1 Electric Power Systems and Equipment Voltage Rating

5. ANSI Z 55.1 Gray Finishes for Industrial Apparatus and Equipments

E. IEC International Electrotechnical Commission

1. IEC 60044 Instrument Transformer

2. IEC 60050 International Electrotechnical Vocabulary

3. IEC 60129 Alternating Current Disconnectors and Earthing Switches

4. IEC 60168 Tests on Indoor and Outdoor Post Insulators of Ceramic Material or Glass for Systems with Nominal Voltages greater than 1000 V

5. IEC 60186 Voltage Transformer

6. IEC 60265-1 High Voltage Switches for Rated Voltage above 1 kV and less than 52 kV

7. IEC 60282-1 High Voltage Current Limiting Fuses

8. IEC 60298 AC Metal Enclosed Switchgear and Controlgear for Rated Voltage 1 kV and less than 52 kV

9. IEC 60470 High Voltage Alternating Current Contactors and Contactor Based Motor Starters

10. IEC 60529 Degree of Protection Provided by Enclosure

F. IEEE Institution of Electrical and Electronics Engineers



1. IEEE 142 Recommended Practice for Grounding of Industrial and Commercial Power System

2. IEEE C37. 09 Test Procedure for AC High-Voltage Circuit Breaker Rated on a Symmetrical Current Basis

3. IEEE C37.20.2 Metal-Clad Switchgear

4. IEEE C37.20.3 Metal Enclosed Interrupter Switchgear

5. IEEE C37 .23 Guide for Metal Enclosed Bus and Calculating Losses in Isolated Phase Bus

6. IEEE C57.12.2 Conformance Test Procedure for Instrument Transformers

7. IEEE C57.13 Standard Requirements For Instrument Transformers

G. NEMA National Electrical Manufacturers' Association

1. NEMA 250 Enclosures for Electrical Equipment

2. NEMA ICS 1 Industrial Control and Systems General Requirements

3. NEMA ICS 2 Industrial Control and Systems: Controllers, Contactors and Overload Relays 600 V

4. NEMA ICS 6 Industrial Control and Systems: Enclosures

H. NFPA National Fire Protection Association

1. NFPA 70 National Electrical Code

I. UL Underwriters Laboratory Inc.

1. UL 1332 Organic Coatings for Steel Enclosures for Outdoor Use Electrical Equipment

1.05 DEFINITIONS

A. dead front: Equipment front without live parts exposed to a person on the operating side of the equipment.

B. listed: Equipment, materials or services included in a list published by an organization that is acceptable to the authority having jurisdiction and concerned with evaluation of product or services that maintains periodic inspection of production of listed equipment or periodic evaluation of services and whose listing states that the equipment, material or services either meets appropriate designated standards or has been tested and found suitable for a specified purpose.

C. live parts: Energized conductive components.



D. low voltage: A class of nominal system voltages 1000 volts or less. In this Section, the intended application low voltage shall be up to 600 volts.

E. main circuit: All the conductive parts of an assembly included in circuit which is intended to transmit electrical energy to the connected load.

F. metal enclosed bus: An assembly of conductors with associated connections, joints, and insulating supports within a grounded metal enclosure. The conductors may be rigid or flexible.

G. medium voltage: A class of nominal system voltages greater than 1000 volts and less than 100,000 volts. Medium voltage levels prevailing at various Royal Commission installations are 4.16 kV Y/2.4 kV, 13.8 kV Y/7.97 kV and 34.5 kV Y/19.92 kV.

H. protection assembly: The assemblies of protective devices and associated control and auxiliary equipment which protects the equipment/feeders. The protective devices include circuit breakers and protective relays.

I. switchgear: A general term covering switching and interrupting devices and their combination with associated control, metering, protective and regulating devices; also assemblies of these devices with associated interconnections, accessories, enclosures and supporting structures used primarily in connection with the generation, transmission, distribution and conversion of electric power.

J. switching device: A device designed to close or open, one or more electric circuits.

1.06 SUBMITTALS

A. The Contractor shall submit to the Royal Commission under the provision of SECTION 01330, the following items for review and/or approval before commencing Work:

1. Shop Drawings and Manufacturer's Literature

a) Shop Drawings in accordance with relevant standards as specified in par. 1.04.

1) Layouts showing concrete pad dimensions, conduit entrance and available space, bus duct connections, electrical ratings, nameplate nomenclature.

2) Single line diagram.

3) Elementary diagram.

4) Control schematics.

5) Interconnection wiring diagram.

6) Front, side and rear elevations showing location of all components.

b) Characteristic curves and instructions for coordinating and setting of protective relays.



c) Characteristic and coordination curves for fuses.

d) Calculations to justify rating and accuracy of CTs and PTs proposed to be furnished. An allowance of 20% shall be assumed for future loads during calculation.

e) List of Manufacturers

1) Medium Voltage Switchgear.

2) Medium Voltage Enclosed Bus.

3) Medium Voltage Motor Controllers.

2. Data sheets and specifications.

3. Part list.

4. Quality Program as specified in SECTION 01450.

B. The Contractor shall submit Field Test Report after completion of Testing and Commissioning.

C. Maintenance Data and Operating Instructions

1. Manufacturers catalogs, giving description of the equipment and its components.

2. Manufacturers operating and maintenance instructions.

3. Installation instructions.

4. Illustrations and diagram of components.

5. Recommended list of spare parts along with price list.

6. Factory field test report.

1.07 QUALITY CONTROL

A. The Contractor and manufacturer shall be responsible for the quality of Work and shall develop and propose programs and methods of construction and testing such as to achieve the specified quality to the approval of the Royal Commission in accordance with SECTION 01450.

1.08 HEALTH AND SAFETY CONSIDERATIONS

A. All works undertaken in relation to this Specification are to be completed in full accordance with the respective health and safety requirements established by the following:

1. Kingdom of Saudi Arabia



a) Legislation. Regulation, Standards and Codes

2. Royal Commission Regulations

a) Standards, Contractual Conditions, and Health and Safety Systems.

3. Contractor

a) Health and Safety Standards and System as accepted by the Royal Commission.

B. In the absence of any of the above, best accepted industry practice shall be employed throughout.

1.09 FACTORY TESTING

A. All equipment/material shall be tested at factory in accordance with latest applicable codes and standards. All types of tests as per applicable codes and standards shall be performed on first unit of every new design. The Contractor shall notify the Royal Commission in writing not less than 30 days prior to the scheduled starting date of the factory tests.

B. The Royal Commission reserves the right of deputing representatives for witnessing the factory test.

C. Upon completion of factory test and before shipment of the equipment/material, the Contractor shall submit 5 certified copies of test reports not latter than 10 days after completion of all factory test for review/approval by the Royal Commission.

1.10 SERVICE CONDITIONS

A. Medium Voltage Switchgear, Medium Voltage Enclosed Bus and Medium Voltage Motor Controllers installed indoors shall be suitable for continuous operation under the following service conditions:

1. Ambient Air Temperature

a) A maximum of 40C.

b) A minimum of 0C.

c) Average temperature measured over a period of 1 month is 35C.

2. Relative Humidity (Average Value)

a) For a period of 24 hours, does not exceed 95%.

b) For a period of one month, does not exceed 90%.

B. Medium Voltage Switchgear, Medium Voltage Enclosed Bus and Medium Voltage Motor Controllers installed outdoors shall be suitable for continuous operation under



the following service conditions:

1. Ambient Air Temperature

a) A maximum of 50C.

b) A minimum of 0C.

c) Average temperature measured over a period of 1 month is 45C.

2. Altitude is less than 1000 m, unless a higher altitude is specified in Contract Drawing.

3. Average Value of Relative Humidity

a) For a period of 24 hours, does not exceed 95%.

b) For a period of 1 month, does not exceed 90%.

4. Relative humidity may be temporarily 100%.

1.11 ENCLOSURES

A. The Enclosures of Medium Voltage Switchgear, Medium Voltage Enclosed Bus and Medium Voltage Motor Controllers installed indoors, outdoors or classified areas shall meet relevant standards listed under par. 1.04.

1.12 DELIVERY, STORAGE AND HANDLING

A. The Contractor shall deliver, handle and store product units in accordance with SECTIONS 01650 and 01660, as well as the following requirements:

1. Provide marking on each item in accordance with the referenced standards. Ship each unit securely wrapped, crated and wrapped or packaged and labeled for safe handling in shipment and to avoid damage or distortion.

2. On arrival at site, the equipment/material shall be checked for completeness and physical damage.

3. Store equipment in secure and dry storage facility as recommended by manufacturer.

4. Lift the equipment using eyes, yokes, and skids provided for the purpose by manufacturer.

5. Store all indoor units protected from weather.

6. Protect all units from physical damage from work of other trades.

7. Provide supports for vertical units to prevent them from overturning.



8. The Contractor shall be responsible for any damage occurring during transportation, handling and storage of the equipment.



PART 2 PRODUCTS

2.01 GENERAL

A. All goods and products covered by these Specifications other than par. 2.01C shall be procured, when available, from an in-Kingdom manufacturer. Procurement of all goods manufactured out-of-Kingdom shall be approved by the Royal Commission.

B. All parts and materials shall be new, good quality, and shall be selected by the Contractor and the manufacturer to perform as specified herein.

C. Where all works covered by and/or interface with Saudi Electricity Company (SEC) the equipment/materials shall comply with SEC standards latest revision, and shall be reviewed and approved by SEC.

D. The equipment supplied:

1. Shall fully conform to or exceed the minimum requirements specified in this Specification.

2. Shall be a product of an original manufacturer.

3. Must have been in commercial production for at least 8 years prior to supply with an established historical data base of good performance.

4. Shall be factory assembled and tested to the extent possible so as to minimize field erection.

E. Items or components of the equipment not specifically covered herein shall be in accordance with latest editions of the referenced codes and standards.

F. The components of assembled unit shall be UL listed or approved by a testing laboratory acceptable to the Royal Commission.

G. The Contractor shall have full responsibility of testing and inspecting the equipment to ensure that the equipment provided shall comply with all regulatory codes, standards, and regulations applicable to the specified service and to the requirements of these Specifications.

H. Finishing of Enclosures

1. Structural steel framework, panels and compartments shall be surface prepared and painted before assembly.

2. All enclosure parts shall be thoroughly cleaned, degreased and given a phosphatizing treatment to inhibit rust and to prime the metal for the finish coating.

3. A 5 micron (0.2 mil) thick electrostatic powder paint coat shall be applied to all surfaces. The paint type and process shall meet UL 1332 for electrical equipment steel enclosures.

4. All enclosure covers and doors shall be painted ANSI Z55.1 No. 61 grey



(Munsell 8.3/G.10/0.54).

2.02 MEDIUM VOLTAGE SWITCHGEAR

A. Technical Characteristics of Medium Voltage Switchgear

1. The switchgear shall be designed for the following electrical values:

a) Rated System Nominal Voltage

1) The rated nominal system voltage shall either be 4.16, 13.8 or 34.5 kV as specified on Contract Drawing.

b) Maximum System Voltage

1) 4.76 kV for 4.16 kV System Nominal Voltage.

2) 15 kV for 13.8 kV System Nominal Voltage.

3) 38 kV for 34.5 kV System Nominal Voltage.

c) Operating Frequency: 60 Hz.

d) Insulation Level

1) One minute Power Frequency withstand Voltage

(a) 19 kV (rms) for 4.16 kV System Nominal Voltage.

(b) 36 kV (rms) for 13.8 kV System Nominal Voltage.

(c) 80 kV (rms) for 34.5 kV System Nominal Voltage.

2) 1.2/50 s Lightning Impulse withstand Voltage

(a) 60 kV (peak) for 4.16 kV System Nominal Voltage.

(b) 95 kV (peak) for 13.8 kV System Nominal Voltage.

(c) 150 kV (peak) for 34.5 kV System Nominal Voltage.

e) Continuous Current Rating

1) As specified in the Contract Drawings.

B. Construction of Medium Voltage Switchgear

1. Medium Voltage Switchgear used for power distribution in Industrial Plants, Power Stations and similar other applications shall have current, voltage, phase, frequency and short circuit rating as specified on the Contract Drawings/Documents.

2. The switchgear shall be of the dead front metal-clad type and shall comprise of individual vertical sections sharing a common main circuit horizontal bus and a common ground bus.

3. The switchgear vertical sections shall be NEMA 1, free standing, factory assembled, 3.2 mm thick steel construction, with hinged front doors and rear access panels of sufficient size to give full access to all components.



4. Adjacent vertical sections and individual compartments shall be isolated from each other by means of sheet steel barriers. The vertical sections shall be bolted together into an enclosed dead-front assembly mounted on an integral base frame.

5. Each vertical section shall comprise of an upper and lower compartments. The lower compartment shall usually contain the main switching devices (circuit breakers etc). The upper compartment shall contain the protective devices, controls, metering and instrumentation effectively isolated from the lower compartment by horizontal metal barriers of full width. Cable raceways shall maintain individual circuit integrity.

6. The door of compartment containing meter and instrumentation shall be strong enough to support meters and other devices mounted on them and shall be provided with stopper to hold the door in open position.

7. The enclosure and internal barriers shall withstand short circuit stresses.

8. The switchgear shall not be configured in a back to back arrangement.

9. The switchgear assemblies shall be suitable for extension at both ends so as to permit the future in-situ installation of vertical section at the end of each bus.

10. Lifting lugs shall be provided for lifting the entire shipping section MV Switchgear without distortion to any part of any enclosure.

11. Each switching assembly equipped for a withdrawable main circuit breaker shall be provided with an automatic metallic safety shutters to prevent access to live equipment when circuit breaker is withdrawn from the panel. The shutter mechanism shall have the following features:

a) Open and close automatically by means of positive drive initiated by the movement of the breaker carriage.

b) Automatically isolate the stationary main circuit contacts (i.e. line and load stabs) when the circuit breaker is moved out of its connected position.

c) Automatically open as the circuit breaker is moved towards its connected position.

d) The busbar shutters shall be colored red and shall have white lettering indicating BUSBAR.

e) The outgoing feeders shall have yellow shutters with black lettering indicating CABLE.

f) The bus tie panel shutters shall be both colored red and shall indicate BUSBAR 1 or BUSBAR 2, as applicable.

12. Control wiring connections between stationary structure and removable element (circuit breaker) shall be provided with self-coupling contacts or manual plug and receptacle for disconnection. The male contacts shall be placed on the removable element while the female receptacles on the



stationary structure. Interlock shall be provided to prevent connection or disconnection of control circuits when circuit breaker is in service position.

13. Each switching assembly compartment shall have a mechanism for levering the circuit breaker between the connected, test and disconnected position.

14. It should be possible to move the circuit breaker from service position to test position and vice versa without opening the panel front door.

15. Integral grounding switches shall be provided for incoming and outgoing feeders and busbars. The grounding switches shall be manually operated, high speed type, having full short circuit making capability.

a) Grounding switch blades shall be directly connected to the main grounding bus of the switchgear and not through switchgear metal frame.

b) Metallic linkages of the grounding switches shall be directly connected to the main grounding bus.

c) Grounding switches shall be operated from the front of the panel. Operating handles of the grounding switches shall be clearly labeled with ON and OFF position.

d) Padlocking facilities shall be provided to enable the grounding switch to be locked in either position.

16. The switchgear shall be provided with a system of preventive mechanical interlocks to protect the equipment, operator and service personnel from the dangers of mal-operation.

a) The interlocks shall be designed to prevent:

1) A closed circuit breaker being inserted into or withdrawn from the service position.

2) A circuit breaker being closed in other than the service, test or withdrawn positions.

3) A circuit breaker being placed in the service position if the secondary contacts plug has not been fitted.

b) It shall not be possible to withdraw the breaker from its housing beyond test position unless the spring stored energy mechanism is automatically or manually discharged. In case of manual discharge, appropriate warning plate shall be provided to caution the operator to manually discharge the spring.

c) Grounding switches shall be mechanically interlocked with associated incoming or outgoing breaker such that grounding switch cannot be closed unless the breaker is withdrawn from service position and that the breaker cannot be inserted in service position unless grounding switch is open.

d) A permissible interlock shall also be provided between opening of



switchgear door and closing of associated grounding switch.

e) Grounding switch of an incoming transformer line shall also be interlocked with transformer HV breaker or transformer HV disconnect switch such that grounding switch cannot be closed unless HV breaker or HV disconnect switch is open and HV breaker cannot be closed unless grounding switch is open.

f) Busbar grounding switch shall be interlocked with the incoming circuit breaker and bus section breaker as well as with all outgoing breakers on the respective bus side, such that the grounding switch cannot be closed unless all associated circuit breakers are open and withdrawn from service position, and the associated circuit breakers cannot be closed unless the busbar grounding switch is open.

g) The busbar grounding truck, when used, shall be so interlocked such that grounding of the busbar shall not be possible unless the associated incoming and bus section breaker(s) as well as all the outgoing feeder breakers are open and withdrawn from service position.

C. Switching Devices

1. The Contractor shall supply drawout or fixed type of switching devices of the ratings as specified on Contract Drawings. Following are various types of switching devices used in Medium Voltage Switchgear:

a) Circuit Breakers

1) Vacuum Circuit Breakers.

2) SF6 Gas Insulated Circuit Breakers.

b) Load Interrupter Switches

1) Air Interrupter Switches.

2) Vacuum Interrupter Switches.

3) SF6 Gas Insulated Interrupter Switches.

c) Fused Load Interrupter Switches.

2. Features of Circuit Breakers

a) Circuit breakers shall be electrically and mechanically trip free, and shall be designed for closure and tripping by remote and local electrical controls.

b) Circuit Breaker shall be provided with anti-pumping device.

c) Circuit breaker shall be equipped with a stored-energy mechanism with the following characteristics: 1) Energy storage shall be via springs.

2) Charging of springs shall be via electric motor(s) with provision for manual charging from the front of the breaker.



3) Energy storage shall be sufficient for an opening-closing-opening operation at rated capabilities (e.g. at rated short circuit current).

4) A mechanical indicator on the front of the breaker shall provide a visible indication of the springs charged or discharged condition.

5) A mechanical actuator (i.e. pushbutton, lever, etc.) shall be provided on the front of the breaker to open and close the circuit breaker poles.

6) Design shall automatically recharge springs immediately after full discharge. Recharge time shall not exceed 10 seconds.

d) Circuit breaker shall be equipped with an operations counter which operates only during the opening cycle.

e) Connection to main circuit stationary stabs shall be via self-aligning contacts.

f) Each circuit breaker shall have an auxiliary switch with minimum of 4 convertible or 2 normally open and 2 normally closed auxiliary contacts available for use, wired to terminal blocks. These contacts shall be in addition to those required for circuit breaker control and indication, as well as space heater control.

g) Circuit breaker shall be equipped with a mechanical indicator on the front of the breaker, giving a visual indication of the open or closed position of the interrupter poles.

h) Circuit breakers of the same type and rating shall be mechanically and electrically interchangeable within the switchgear assembly.

i) Vacuum circuit breaker shall use vacuum interrupters to interrupt fault current quietly, adopting reliable method for quenching the arc. The vacuum circuit breaker shall have the following features:

1) The chambers of the interrupter shall be sturdy protecting interrupter against shocks and shall be sealed properly to prevent ingress of dust and humidity retaining the dielectric strength.

2) The circuit breaker shall be provided with:

(a) Virtually maintenance free vacuum interrupter contacts.

(b) Direct reading erosion indicator for vacuum interrupter contacts.

j) The insulating enclosure of SF6 circuit breaker shall be effectively sealed to prevent ingress of moisture, dust and other contaminants into gas compartment. Following alarms for indicating insufficient gas density in the circuit breaker shall be provided.

1) Alarm at 10% above minimum safe operating gas density.

2) Alarm in the event of gas density falling below the minimum safe operating limit.

3. Features of Load Interrupter Switches



a) Interrupter switches shall be 3-pole, single-throw, complete with manual operating mechanisms and position indicator.

b) Interrupter switches shall be actuated through a built-in, quick-make, quick-break mechanism to assure high-speed closing and opening independent of the speed of the manual switch operation.

c) Quick make, quick break operation shall be achieved through spring stored energy operating mechanism. The spring operated mechanism shall be located in a compartment free of contamination and corrosion.

d) To avoid the hazard of inadvertent slow closing or opening on a live circuit, the quick-make, quick-break mechanism shall be non-defeatable.

e) Vacuum and SF6 switches shall have CLOSED, OFF and GROUND positions.

f) Interrupter switch shall be self-latching in closed, off and ground positions and shall have provisions for padlocking in all positions.

g) The operating handles shall be non-reversing type to prevent operator reversal or kick-back.

h) A means of visually verifying the open and closed contact positions of interrupter switch shall be provided.

i) The position indicators shall indicate the positions of the switch as well as condition of charging spring.

4. Features of Fused Load Interrupter Switches

a) The fuses shall be of the self-contained current limiting type to provide fast, clean interruption with minimum let-through current.

b) Fuses shall operate during the first quarter cycle on maximum fault condition with no expulsion of gases or foreign matter from the tube.

c) Fuses shall be supplied with a visible blown fuse indicator.

d) Fuse operation shall automatically disconnect all 3 phases of the load to prevent single phase operation.

e) Fusible switches shall have interlocks to prevent fuse removal with switch in closed position.

5. Generally, circuit breakers are used as switching devices for high amperage rating while load interrupter switches or/and fused load interrupter switches are used for low amperage rating.

D. Relays, Meters and Instruments

1. Relays, meters, indicating lamps and instruments shall be provided as specified in the Contract Drawings/Documents and shall be located on a separate low voltage compartment of each switchgear panel.



2. All meters and instruments shall be suitable for operation at a frequency of 60 Hz. The instruments shall be protected from the stresses resulting from the momentary and short circuit currents indicated in this Specification.

3. All meters shall have dust-tight cases flush or semi-flush mounted on the front door.

4. Each voltmeter and ammeter shall be provided with a selector switch for reading each phase-value.

5. All watt-hour meters shall be drawout type with built-in test connections.

6. Three phase or 3single phase transducers for remote indication shall be provided as shown on the Contract Drawings/Documents. The transducers shall have accuracy class of 0.25% or better and shall be as follows:

a) Current transducer shall have an input rating of 0 to 5 amp, 60 Hz and an output rating of 4 to 20 mA.

b) Voltage transducer shall have an input rating of 0 to 150 V and an output rating of 4 to 20 mA.

7. The switchgear shall be provided with following indicating lamps in addition to those shown on the Contract Drawings/Documents. The indicating lamps shall be removable from the front of the panel.

a) Red for circuit breaker closed position.

b) Green for circuit breaker open position.

c) Amber for circuit breaker tripped position.

d) White for availability of control supply.

8. All protective-type relays shall be suitable for operation at a frequency of 60 Hz. The relays shall withstand the stresses resulting from the momentary and short circuit currents indicated in this Specification or elsewhere. The manufacturer shall guarantee the compatibility of ground sensor current transformers and the associated instantaneous overcurrent relays.

9. All protective-type relays shall have draw-out type cases, shall be semi-flush-mounted on the front door operating face of the equipment, and shall be of the rectangular dust tight type. The relay cases shall be provided with glass covers and gaskets to render them dust-tight. Auxiliary relays shall be surface mounted at easily accessible locations in each cubicle. All protective relays shall be equipped with built-in targets or indicating lights which indicate a trip condition. Typical protective relays used for protection of feeder/equipment are listed below.



a) Overload (51).

b) Overload lockout (86).

c) Locked rotor (48).

d) Phase unbalance (46).

e) Ground fault (50/51G).

f) Undercurrent /Under power (37).

g) Under/Over frequency (81).

h) Differential (86).

i) Undervoltage (27).

j) Overvoltage (59).

10. Solid state type relays are preferred when the characteristics and application of these relays have a minimum of 2 years of highly reliable service at similar facilities.

11. It shall be the responsibility of the switchgear manufacturer and the Contractor to complete the detail design of the complete protective relaying system in accordance with the functional requirements shown in the one-line and schematic diagrams. A coordination study shall be provided for the Royal Commissions review.

12. Each tripping (normally open) contact of the lock out relays shall be provided with a test switch to facilitate device testing. Connections to the test switches shall be shown on the schematic diagrams.

13. Meters, instruments and indicating type transducers shall have test facilities separate from protection, so that testing and calibration can be done without equipment outages. Test facilities shall be mounted on the front panel.

14. Upper edge of protective relays and meters shall be no higher than 2.2 m to allow convenient maintenance, inspection, target reset, and testing from ground level.

15. The accuracy class of relays and meters shall be as shown on the Contract Drawings/Documents.

16. The AC and DC controls shall be compatible with control power supply indicated on the Contract Drawings/Documents.

E. Current Transformer (CT)

1. The Contractor shall supply single/multi ratio CTs as specified on the Contract Drawings/Documents.



2. The ratings and accuracy class of current transformers supplied with switchgear shall be as specified on the Contract Drawings/Documents. The rated burden of CTs shall be a minimum of 125% of the load burden.

3. The mechanical and thermal current ratings of CTs shall be coordinated with the momentary and short circuit current of the associated circuit breaker, respectively.

4. Each secondary connection of all current transformers shall be wired to short circuiting type terminal boards or test blocks located in the secondary termination compartment.

5. When secondary windings of current transformers are required to be grounded, they shall be grounded at one point only at the terminal boards or test blocks which shall be readily accessible and clearly identified. The common or ground lead shall be a properly color-coded continuous insulated copper conductor to the ground bus.

6. Phase current transformers shall be torroidal ring type mounted so they slip over the primary contact insulating tube (spout) on the rear wall of the breaker compartment. There shall be space for a minimum of 4 standard accuracy CT's per phase.

7. CTs used for differential schemes shall not be used for other relaying or metering circuits.

8. All current transformers used in differential or partial differential schemes shall use the same tap ratio and shall have compatible excitation and saturation characteristics and shall conform to the relay manufacturers requirement.

F. Voltage Transformer

1. The ratings and accuracy class of voltage transformers supplied with switchgear shall be as specified on the Contract Drawings/Documents.

2. The voltage transformer shall be protected by fast acting fuses placed on primary and secondary side.

3. Voltage transformer shall be dry type, and shall be mounted on a draw-out frame. In the disconnected position, the primary and secondary circuits shall be automatically disconnected, and primary fuses grounded.

4. The BIL of the transformers shall be the same as that of the switchgear.

5. External connections to the potential transformer secondary shall be through a test block.

G. Switchgear Buses

1. The main phase and neutral buses of the ratings as indicated on the Contract Drawings/Documents shall be isolated from any power and control cables by means of grounded metal barriers or enclosures.

2. Buses shall be braced to withstand without damage the forces produced by the



maximum available instantaneous short-circuit currents.

3. Main bus bars shall have the same cross-section and rating throughout the switchgear. Tapered bus bar systems are not acceptable.

4. Vertical bus bar risers shall maintain the same cross-section and rating through the panel and shall have a continuous rating of not less than the sum of the nameplate ratings of the interconnected circuits.

5. Bus bars shall be made of high conductivity copper with silver plated joints.

6. The buses shall be supported by heavy duty, high dielectric strength, non-hygroscopic insulating material. The rated strength of porcelain elements, in their most probable mode of failure, shall not be less than 2.4 times the working stress.

7. The continuous and momentary current rating of buses shall be as specified on the Contract Drawings/Documents. The following requirements shall apply to bus connection:

a) All bolted connections shall be silver plated and shall provide permanent high-pressure contact between the silver-plated surfaces.

b) All buses and heavy current-carrying connections shall be fully insulated with epoxy insulation of a flame retardant and non-hygroscopic type. Where possible, all buses and connections shall be completely insulated at the factory.

8. The phase sequence of the assembled 3-phase buses shall be A, B, C counting from front to back, top to bottom, or left to right, as viewed from the front of switchgear.

9. The ground bus of size as indicated on the Contract Drawing/Documents shall be provided over entire length of the assembly, with provisions for extension at either end for future expansion.

H. Space Heaters and Lamps

1. Switchgear shall be equipped with space heaters in each vertical section. The heaters shall operate on voltage level stated on the Contract Drawings/ Documents and shall be completely wired and interconnected between cubicles of each line-up for a single feeder. The space heaters shall be thermostatically controlled and provided with ON/OFF switch mounted in the switchgear.

2. One fluorescent light controlled by toggle or door switch shall be provided in each vertical section.

I. Internal Wiring and Terminal Blocks

1. All wiring within the switchgear shall be installed and tested at the factory unless otherwise specified. All wiring shall be heat and flame retardant, rated 90C maximum operating temperature, type SIS as listed in ANSI/NFPA 70 or approved equivalent, rated 600/l000 V, with insulated, tinned, stranded



annealed copper conductor, and shall not be smaller than 2.5 mm. All CT secondary related circuits shall not be smaller than 4 mm.

2. For the wiring of solid state devices, smaller size wires may be acceptable up to the first termination point, only if the associated device cannot accommodate larger wire sizes.

3. All wires shall be adequately rated for thermal withstand of short circuit currents.

4. All wiring shall be made without splices. The control wires shall be multi-stranded flexible and shall be terminated with ring type terminals. Spade type or boot lace type crimps shall not be used.

5. Terminal blocks shall be mounted on DIN rails. The DIN rails shall be mounted on the bottom and sides of the panel at an angle of 45 towards the front of the panel. If front access only is applicable, then the blocks shall be angled towards the front of the panel.

6. Terminal blocks shall be grouped according to function, i.e. Power Supplies (AC or DC), VT, CT, DC controls, annunciation, SCADA etc. The function shall be labeled accordingly. Terminal blocks for different voltages (AC or DC) shall be located on separate DIN rails.

7. The CT terminal blocks at the first accessible point of termination shall have shorting and grounding facilities by means of a copper bar with shorting screws.

8. Not less than 10% spare terminals shall be provided on each terminal block.

9. All spare contacts from protective relays or tripping relays shall be wired to the terminal blocks for future use. At least 2 spare (2 NO + 2 NC) contacts of lockout relay shall be wired to the terminal block for future use.

10. All wiring internal to the switchgear assembly shall be laid in accessible wiring troughs throughout the entire length of the switchgear assembly.

11. Internal wiring between the breaker and the LV compartment shall be bundled and neatly formed. There shall be no wiring run as single cores through grommets.

12. The AC wiring shall be bundled separately from DC wiring in the same raceway. Signaling cables shall be shielded type and run in a separate raceway and shall be separated as far as practical from all LV power cables and at right angle to such wiring when the spacing is less than 300 mm.

13. Cable supports shall be provided for wiring run directly to instruments or devices. Wiring extensions from raceways or bundles to instruments and devices shall be neatly formed, securely tied or clamped and supported to the switchgear framework. Bends in the wiring shall be carefully made in such a manner that the insulation is not damaged.

14. All internal wiring terminations shall be identified by legible markings at the device terminals. Markers shall be of ferrule type, permanently marked and



shall be made of material that will not deform or deteriorate and shall withstand a temperature of 90C. Adhesive type terminal markers are not acceptable.

15. Where panels are to be shipped in sections and assembled in the field, the wiring between sections shall be provided preformed. One end of the wire shall be terminated on terminal block and the other end shall be bundled and tagged properly.

J. External Cabling

1. Power Cables

a) Provisions shall be made for the connection of all power cables including proper terminal connectors or lugs, clamps, or terminations. The location of the power cable connections shall be arranged to:

1) Ensure that cable entry is exactly below the termination point.

2) Provide adequate vertical space required for training incoming cables from conduit entry to connectors and to provide adequate space for cable termination devices.

b) In case an extension box is required to meet the vertical space requirement, the extension box shall be a part of the switchgear supply.

c) Terminal lugs for power cables shall be suitable for use with copper or aluminum conductor material.

d) The cable termination compartments shall be designed to accept heat shrinkable cable terminations. The boots over the cable terminals, if required, shall also be of heat shrink or molded PVC type.

e) All terminal lugs for power cables shall be of bolted type with two crimping elements per lug.

f) Terminals for conductors 400 mm and larger shall be suitable for 4-hole NEMA pad, 12 mm stud. For conductors smaller than 400 mm, terminals shall be suitable for 1-hole NEMA pad, 12 mm stud.

2. Control Cables/Wires

a) All external control cables and wires shall be brought to the panel from the bottom, unless otherwise specified.

b) Control cables and wires shall enter the panel through suitable cable glands to prevent contact with sharp metal edges. The gland-plate assembly shall be vermin proof.

K. Nameplates and Markings

1. All nameplates/equipment tags shall be attached with stainless steel screws.

2. The manufacturer's shop order number, date, and catalog designation should be indicated on the switchgear nameplate.



3. All panel mounted devices shall be identified by nameplates.

4. Protective relay nameplates shall be provided to indicate protective function, ANSI device number.

5. Device nameplates shall be nominal 60 by 25 mm laminated plastic with engraved black 6 mm characters on a white background.

6. Warning nameplates shall be provided on each compartment door in which an external voltage source (i.e. a voltage source which is not derived from within the switching assembly) is terminated, reading: "CAUTION - THIS UNIT CONTAINS AN EXTERNAL VOLTAGE SOURCE." These nameplates shall be engraved laminated plastic with white characters on a red background and shall be written in both Arabic and English.

7. Manual trip devices shall be labeled: "Manual Trip."

8. A nametag/nameplate shall be provided at each space heater terminal block to which the Buyer's field cable terminates. The labeling shall indicate the service voltage.

9. A warning sign shall be fastened by screws on each rear panel both in Arabic and English. The warning sign shall indicate DO NOT OPEN THIS PANEL UNLESS THE GROUNDING SWITCH IS IN ON POSITION.

L. Enclosures

1. Indoor Enclosure

a) The indoor metal clad switchgear shall be enclosed in a ventilated general purpose enclosure having degree of protection IP 41.

b) Ventilation or pressure relief openings shall be so arranged that in case of any arching fault inside the switchgear, the gas or vapor escaping will not endanger personnel operating the switchgear and will not enter into adjacent panels thereby preventing spreading of the fault.

c) All ventilation louvers shall be vermin-proof and shall be provided with removable filters to minimize ingress of dust and dirt.

2. Outdoor Enclosure

a) For outdoor installations, indoor metal clad switchgear shall be housed in weatherproof outdoor enclosure having degree of protection IP 64.

b) The location of door opening (rear/front) and that of cable entry (top/bottom) shall be as stated on the Contract Drawings/Documents.

c) The outdoor enclosure shall be walk-in type with operating and maintenance aisle in the front, rear and sides of the switchgear. The aisle shall be of sufficient size to permit interchanging of removable elements.

d) The outer enclosure shall have an access door at each end equipped



with safety latches to permit opening from within the outer enclosure under all conditions. The doors shall be provided with hydraulic door closer and shall be key lockable.

e) The outdoor enclosure shall be supplied with double walls on the roof, doors and all sides of the enclosure.

1) The gap between two walls shall be a minimum of 50 mm and shall be filled with thermal insulation.

2) The thickness of exterior plate shall not be less than 3 mm.

3) The thickness of interior plate shall not be less than 1.5 mm.

f) All exposed handles, screws and hinges shall be made of non-corrosive material or shall be hot-dip galvanized or stainless steel for outdoor locations, and cadmium and chromium plated for indoor equipment. All bolts, nuts and washer shall be of similar type of metal.

g) The outdoor enclosure shall be provided with suitable number of window air conditioners to maintain inside temperature. Control Panel shall be mounted in the enclosure to control and schedule the time operation of each unit.

h) In case the components in switchgear such as relays etc. which requires AC, are not installed in the switchgear or if all the components in switchgear are capable of withstanding the outdoor temperature as specified in par. 1.11, then these switchgears shall be installed outdoor without housing in enclosures as specified in par. 2.02 L.2.a with degree of protection IP 64.

2.03 MEDIUM VOLTAGE ENCLOSED BUS

A. Construction of Medium Voltage Enclosed Bus

1. Bus ducts used for inter-connecting groups of metal-clad switchgear, power transformers or other related equipment shall have current, voltage, phase, frequency and short circuit rating as specified on Contract Drawings/Documents.

2. For Technical Characteristic of Medium Voltage Enclosed Bus, refer to par. 2.02 A.1.

3. The Contractor shall supply all necessary equipment, connection flanges, wall entrance seals, transformer and/or equipment taps, elbows, offsets, wall supports, expansion joints, splicing materials, terminal connectors to make a complete installation.

4. Enclosed bus shall be isolated phase, segregated or non-segregated phase buses as specified on the Contract Drawings/Documents.

5. The bus shall be a totally enclosed non-ventilated construction.



6. Enclosures of bus shall be fabricated from galvanized carbon steel, non-magnetic stainless steel or aluminum alloy.

7. Sandwich type constructed bus duct assemblies shall not be acceptable.

8. Enclosures for metal enclosed bus assemblies located outdoor shall be watertight and weatherproof. Top cover joints and joints with end flanges shall be gasketed and protected with a metallic sealing strip.

9. Outdoor enclosures shall have a sloped top that prevents collection of water. Joints shall be watertight by design and not dependent on the gasketing material for water tightness.

10. Enclosure fittings shall include drains which have removable, threaded, plugs located at low points in the metal enclosed bus assembly installation.

11. Enclosures shall have removable covers for access to the bus joints and other internal devices. Access openings in horizontal sections shall be located on the bottom of the enclosure. These access openings shall have removable covers with Neoprene gaskets.

12. Enclosures for metal enclosed bus assemblies shall be made from No. 11 gage metal as a minimum. Metal enclosed bus assemblies, rated 2000 A or greater, shall be made from non-magnetic metal to limit induced current losses and circulating currents by breaking the magnetic path.

B. Bus Bars

1. The bus bars shall be fabricated of 99% pure copper. The contact surfaces at joints shall be silver plated.

2. The bus bars shall be full size and continuous throughout. Tapered bus bars are not acceptable.

3. Bolted bus bar connections shall be made with the bolts passing through the bus bars in a way that they can be properly torqued and locked in place to maintain full and uniform pressure under all operating conditions.

4. Temperature rise of bus bar joint at rated current and frequency shall not exceed bus bar rise by more than 5C and in no case shall such bus bar joint temperature rise exceed 55C above ambient of 50C.

5. Bus bar and joints shall be manufactured to remove sharp edges, and to minimize corona. Joints shall be covered with formed insulating boots.

6. Bus bars shall be insulated with flame-retardant, non-hygroscopic insulating material rated for continuous operation at 120C.

7. Suitable connectors shall be furnished to bond the enclosure (or ground bus) of the bus duct to the ground bus or ground terminal of the equipment, to ensure continuity of the equipment grounding circuit between the connected equipment.

8. The design shall accommodate expansion/contraction of the bus bars and



housing due to temperature changes.

C. Bus Bar Supports

1. The bus bars shall be supported on insulator which shall be bolted to mounting plates to hold the bus firmly in place and ensure rigidity.

2. The bus bars shall be braced as necessary to withstand mechanical and thermal effects without damage or deformation resulting from an asymmetrical short circuit current as specified in the Contract Documents.

3. The bus insulation and insulating supports shall be made of flame retardant, track resistant, non-hygroscopic materials. Insulators may be molded glass reinforced polyester or wet process porcelain post type insulators.

D. Space Heaters

1. Thermostatically controlled space heaters shall be provided in metal enclosed bus assemblies as specified in Contract Drawings/Documents.

2. The Vendor shall determine the required wattage of the heaters based on the volume and surface area of the metal enclosed bus assemblies.

3. Heating elements shall have voltage rating of approximately twice the supply voltage indicated on Contract Drawings. Heaters and associated circuits shall be rated for continuous duty.

4. The space heaters shall be mounted at regular intervals in such a way that those shall be accessible and removable from outside the enclosure with the bus bars energized.

5. Each circuit heater shall be fused and have knife blade disconnect. All terminations with fuses and disconnects shall be located at a terminal box for connection to the power supply.

E. Nameplates

1. Nameplates shall be permanently attached to Metal Enclosed Bus assemblies. The nameplates shall be abrasion resistant, stainless steel and attached with stainless steel hardware. Entries shall be marked by etching, engraving or other permanent marking method.

2. Danger and warning indicators shall be written in both Arabic and English, utilizing white characters on a red background. If specifically noted Arabic warning indicators may be supplied by others.

2.04 MEDIUM VOLTAGE MOTOR CONTROLLERS

A. Construction of Medium Voltage Motor Controllers (MVMC)

1. MVMC used for control of medium voltage motors shall have current, voltage and short circuit rating as specified on the Contract Drawings/Documents.



2. The MVMC shall be of the metal-clad type and shall comprise of individual vertical sections sharing a common main circuit horizontal bus and a common ground bus.

3. The MVMC vertical sections shall be NEMA 1, free standing, factory assembled, 2 mm thick steel construction, with doors and access panels of sufficient size to give full access to all components.

4. Each vertical section shall be properly sized to dissipate the heat generated by the controller within the limits of the specified environmental operating conditions.

5. Adjacent vertical sections and individual compartments shall be isolated from each other by means of sheet steel barriers. The vertical sections shall be bolted together into an enclosed dead-front assembly mounted on an integral base frame.

6. The MVMC assemblies shall be suitable for extension at both ends so as to permit the future installation of vertical section at the end of each bus.

7. Roof lifting attachments/lugs shall be provided for lifting the entire shipping section without distortion to any part of any enclosure.

8. Each controller shall have a separate, front accessible, low voltage control compartment. The compartment shall be completely isolated, using metal barriers between the low voltage compartment and the power cell and/or main power bus compartments for utmost safety.

9. Meters, protective relays, selector switches, indicating lights, etc., shall be mounted on the front of the low voltage control panel, and arranged in a logical and symmetrical manner.

10. Main isolating switch of the rating as specified in the Contract Drawings/Documents shall be located in incoming compartment. The main isolating switch shall be externally operated, 3-pole, gang operated, fixed mounted no-load-break type.

B. Bus Bars

1. General

a) Each vertical section shall be provided with a main 3-phase insulated horizontal bus at the top, and with a 3-phase insulated vertical bus to distribute power to the combination starters and feeder units in the vertical section. A full neutral copper bus bar shall be provided as specified on the drawing. A continuous bare copper ground bus shall be provided throughout the length of the control center.

b) All bus bars shall conform to ASTM B187, 98% conductivity copper with silver plated contact surfaces. Horizontal and vertical buses shall be tin or silver plated and shall be braced to withstand the minimum RMS symmetrical fault current as specified on the drawing. Bus ratings shall be based on 50C rise over a 40C ambient.



c) All buses shall be rigidly held by bus supports which have high and indefinitely long lasting dielectric qualities. They shall be moisture resistant, non-carbonizing, non-tracking and have vertical creepage surface to prevent faults due to build up of conductive dirt. Bus bar spacing and spacing of bus fastening point shall be as specified in UL 845.

d) The phase arrangement on 3-phase horizontal common power and vertical buses shall be A, B, C from front to back, top to bottom, or left to right, as viewed from the front of the Motor Control Center.

2. Horizontal Bus Bar

a) Each MVMC section shall contain three main horizontal bus bars, housed in an isolated compartment, which shall run continuously through all sections of MVMC, with provision made for extension at either end for future expansion.

b) Bus bar and other types of bolted connections in the bus compartment shall be accessible from the front of MVMC line up through sliding or removable covers in each vertical section.

c) The main horizontal bus shall be continuous and unspliced within each shipping section. Where the buses are spliced for shipping purposes, the contact surfaces at the splice joint shall be tin or silver plated. The bolts, springs, washers, splice plates, and instructions required to complete the splice shall be provided.

d) The main horizontal bus rating shall be as specified on the Contract Drawings.

3. Vertical Bus Bar

a) Each vertical section shall contain 3 full length copper vertical bus bars connected to the horizontal main bus bars at the top of each vertical section.

b) The vertical buses shall be isolated from the starter unit area of the vertical sections by a barrier made of a rigid insulating material.

c) The vertical bus bar shall maintain the same cross-section and rating throughout the panel and shall have continuous current rating suitable for sum of maximum load currents (present and future) to be connected to the bus.

4. Ground Bus Bar

a) A continuous, horizontal tin-plated copper ground bus of cross-sectional area 6 x 50 mm shall be located across the complete length of MVMC lineup, with provisions made for extensions at either end for future expansion.

b) Provisions shall also be made to terminate a 120 mm copper ground system cable at each end. The ground bus shall be routed at the lower



rear of the line-up.

c) A vertical grounding bus shall be provided in each vertical section that makes contact with plug-in units before the bus stabs engage the vertical bus.

C. Controllers

1. General Starter Requirements

a) MVMC Incomer Circuit Breaker

1) Each MVMC shall be equipped with a main incomer circuit breaker as shown on the Contract Drawing. This circuit breaker shall isolate entire MVMC from incoming power supply.

2) All controllers shall be supplied with a means of isolating the unit from the vertical MVMC bus bars. When the disconnecting means is open, the controller shall be completely de-energized downstream from power supply from the bus bar.

3) Provisions for connecting an external 120 V control power source meeting NEC requirement shall be provided for testing purpose. The power source shall be mechanically and electrically interlocked to be operable only when the main disconnect of fixed units is open, or when the plug-in unit of draw-out designs is withdrawn to the test position.

b) Main Power Fuses

1) Controller shall be equipped with primary current limiting fuses in all 3 phases. The ratings of the fuses shall be as specified in the Contract Drawings/Documents.

c) Contactors

1) Contactor shall be a 3 pole, electrically operated, magnetically held, drawout type air, vacuum or SF6 unit as indicated on the Contract Drawings/Documents. The contactor shall be capable of being racked onto or off the primary stabs in MVMC fixed housing.

2) Contactor shall be equipped with 2 normally opened spare auxiliary contacts and 2 normally closed spare auxiliary contacts. These contacts shall be wired to a terminal block located on the controller assembly.

3) Either pilot lights or a mechanical indicator shall be provided to show whether the main contactor position is open or closed.

4) Contactor assemblies shall have permanent, full-travel alignment guides, to position the contactor in the enclosure for insertion and withdrawal.

5) Barriers shall be installed between fuses, and between the blades of a 3-pole load break switch.

6) Mechanical and electrical interlocking shall prevent:

(a) The contactor closing, unless the primary disconnecting



devices are in full contact or separated by a safe distance.

(b) Opening of the medium-voltage compartment door without isolating the starter.

(c) Closing of the line contactor with the door open.

d) Control Power Transformer (CPT)

1) Controller units shall be equipped with a suitable rated CPT mounted on a draw-out unit.

2) Both CPT primary leads shall be provided with current limiting fuses. One lead of the 120 V secondary shall be grounded and the other lead shall be fused.

3) Where draw-out contactors are used, an interlock shall open the CPT secondary circuit upon drawing-out the contactor.

e) Current Transformer (CT)

1) CTs shall be provided, based on motor full-load current shown on the single line diagram.

2) CTs shall be insulated for the full voltage rating and shall be mechanically rated to withstand the maximum short circuit momentary rating of MVMC. The accuracy shall be as specified on Contract Drawings/Documents.

f) Protection, Control and Metering

1) Preferred system of protective relaying, metering and monitoring shall be microprocessor based configurable controller.

2) Microprocessor shall be capable of monitoring electrical current, receiving commands either by contact closures or digital data, giving commands by means of contact closure to the motor starters and other devices under its control, and transferring information by alphanumeric display to the operator and by digital signals to other equipment.

3) Microprocessor unit shall be mounted on the door of the starter. Specific data entry to suit the actual motor application shall be programmed into the device in accordance with manufacturers instructions.

4) Unit shall draw its power from a control power transformer located in the starter unit of 120 V power supply or as shown on the Contract Drawings.

5) Microprocessor based motor protection unit shall have adjustable setting and shall provide the following protective functions:

(a) Overload (51).

(b) Overload lockout (86).

(c) Locked rotor (48).

(d) Phase unbalance (46).

(e) Zero sequence ground fault (50/51G).



(f) Undercurrent / under power (37).

(g) Thermal overload (49).

(h) Bearing overtemperature (38).

(i) Under/Over frequency (81).

(j) Differential (86).

(k) Undervoltage (27).

(l) Overvoltage (59).

(m) Phase reversal (47).

6) Monitoring microprocessor shall have the following digital displays:

(a) Voltage.

(b) Current (RMS of each phase).

(c) Running time in hours.

(d) Power factor.

(e) Frequency.

(f) Demand.

2. Full Voltage Non-Reversing Starter (FVNR)

a) Provide single contactor for starter in accordance with General Starter Requirements as specified in par. 2.04 C.1.

3. Full Voltage Reversing Starters

a) In addition to the General Starter Requirements as specified in par. 2.04 C.1, Full Voltage Reversing Starters shall be provided with:

1) Two contactors 1 for forward running and 1 for reverse running of a motor. Contactors shall be provided with mechanical and electrical interlocks to prevent simultaneous closing of both the contactors.

2) One forward-reverse-stop push button.

4. Reduced Voltage Non-Reversing Reactor Type Starter

a) In addition to the General Starter Requirements as specified in par. 2.04 C.1, Reduced Voltage Non-reversing Starters shall be provided with:

1) Two contactors.

2) Three starting reactors with 50, 65, and 80% voltage taps.

3) Definite time transfer relay.

5. Reduced Voltage Non-Reversing Autotransformer Type Starter

a) In addition to the General Starter Requirements as specified in



par. 2.04 C.1, Reduced Voltage Non-reversing Autotransformer Type Starters shall be provided with:

1) Three contactors.

2) Autotransformer with 50, 65, and 80% voltage taps.


6. Reduced Voltage Star Delta Starter

a) In addition to the General Starter Requirements as specified in par. 2.04 C.1, Reduced Voltage shall be provided with:

1) Two contactors.


D. Space Heater and Lamp

1. Provide space heater for MVMC as specified in par. 2.02 H.

2. Motor Space Heater

a) When required, an additional normally closed heavy-duty auxiliary contact shall be provided on the motor starter contactor, to allow motor space heater operation when the motor is not in operation.

b) Motor space heaters can be fed from the motor starter CPT. CPT shall be appropriately sized to accommodate the additional heater load.

3. One fluorescent light controlled by toggle/door switch shall be provided in each vertical section.

E. Internal Wiring and Terminal Blocks

1. Internal Wiring and Terminal Blocks shall be as specified in 2.02 I.

F. Nameplates and Markings

1. Each unit on MVMC shall have nameplates on the outside face of the door, to indicate service, as shown on the single line; safety precautions; and any other information deemed necessary for personnel protection. Safety related information shall be in both Arabic and English.

2. The devices within MVMC shall be identified with a nameplate. Protective relay nameplates shall be provided to indicate protective function, ANSI device number.

3. The equipment mounted through the doors shall have nameplates provided on both sides of the mounting surface. Devices mounted inside MCC shall have the nameplate mounted on the equipment-mounting panel in the proximity of the device.

4. The overall MVMC assembly shall be centrally and visibly marked with a nameplate of letters 18 mm or larger, including:



a) Manufacturers name,

b) Model and serial numbers,

c) Assembly manufacture date, AND

d) The Royal Commissions purchase order number.

5. The nameplates shall be laminated and comprise engraved letters, with a white outer surface and a black core.



PART 3 EXECUTION

3.01 GENERAL

A. The Contractor shall provide all materials, equipment and labor as deemed necessary for complete and proper execution of the work.

B. After the installation is complete and properly adjusted, the Contractor shall conduct operating tests. The various equipment and systems shall be demonstrated to operate in accordance with the requirements of the specifications. Tests shall be performed in the presence of the Royal Commission's representative. The Contractor shall provide electric power, instruments and personnel necessary for performing the various tests.

3.02 INSTALLATION OF EQUIPMENT

A. General

1. All installation details, write-up on handling of the equipment, instruction manuals and latest revised drawings furnished by manufacturer shall be available at site prior to installation of the equipment. These details shall be reviewed by the Royal Commissions representative. The details and instructions furnished in these documents shall be followed carefully during installation of the equipment.

2. Ensure that all buildings and rooms for the installation of the equipment are ready, complete and clean. All embedded channels and anchor bolts shall be in place as per layout drawings.

3. All the facilities required for transportation of electrical equipment from store to site such as competent manpower, crane and trucks of adequate capacities shall be supplied by the Contractor.

4. All equipment moved to the site shall be inspected for damage or deterioration during storage. Tag numbers and nameplates shall be verified with the details given on the drawings.

5. The Contractor shall also provide the equipment manufacturers services of a competent and experienced engineer to supervise the erection of the equipment, the field tests, initial operation, and instruct and train the Royal Commissions personnel in the correct installation, operation, service, and maintenance of the equipment.

B. Installation of Medium Voltage Switchgear and Medium Voltage Motor Controller

1. Each Medium Voltage Switchgear and Medium Voltage Motor Controller shall be mounted on concrete pad of appropriate size and anchored to 2 suitably sized channel iron sills, by tack welding or bolting. Sills shall be furnished by the Contractor to suit the motor control center and shall be leveled and grouted flush into the concrete pad by the Contractor.

2. Ensure that the clearance around switchgear and MVMC shall be as per Article 408.8 of NEC.



3. All alignment and adjustment shall be completed as per Installation Manual.

4. After the equipment has been installed and secured to the floor. The Contractor shall touch up all spots where original factory paint was scratched or burned off during welding.

5. All shipping sections shall be installed on foundations and connected together as per layout drawings and manufacturers recommended practice.

6. All bus bars of the shipping sections shall be connected together by stainless steel nut and bolts as per the manufacturers instructions. The torque applied on nut and bolts shall be as recommended by the manufacturer.

7. All power and control wiring shall be completed as per drawings.

8. Circuit Breakers and other draw out units are installed properly.

9. Ground complete Switchboard and Motor Control Center and Motor starters as specified in SECTION 16060.

C. Installation of Medium Voltage Enclosed Bus

1. Ensure that the equipment to which the bus duct are to be connected are installed.

2. Transport the bus duct to the location where it is required to be installed and ensure that there is no damage or deterioration during storage.

3. Assemble the bus sections as per relevant drawing and manufacturers installation instructions.

4. Connect all bus sections with connecting hardware kit supplied by bus manufacturers such as nut, bolts, flat washer and locking devices etc.

5. All bus bar joints shall be tightened in accordance with the manufacturers instructions.

6. Install gasket, frames and closure hardware at shipping splits and equipment interface.

7. Install trapeze type hanger bars for every 1.5 to 2.1 m spacing or as indicated on the Contract Drawings to support bus duct installations to be supported from roof. Or install brackets for vertical or horizontal mountings for self-supporting bus duct.

8. Ground complete bus duct assembly as specified in SECTION 16060.

3.03 TESTING AND COMMISSIONING

A. General

1. The Contractor shall carry out all site tests in accordance with approved test procedure to ensure that the equipment and materials comply with the



specifications and operational requirements. All tests are subject to witnessing by the Royal Commissions representatives.

2. At least 4 weeks prior to scheduled tests, the Contractor shall submit to the Royal Commission an outline of the plan and procedures to be used in performing the site inspection and site tests. This outline shall include a brief description of the test equipment, connection diagrams, proposed tests and procedures, test sheets, calculations, reference drawings and minimum/maximum test and performance values in conformance with applicable standards which shall be used to determine conformance with the specification and acceptability of the equipment and installation.

3. All testing equipment shall be calibrated by approved authorities and calibration certificate shall be provided to the Royal Commission for review and approval.

4. Upon completion of installation and prior to final acceptance, each component of each system shall be tested to the complete satisfaction of the Royal Commission. The Contractor shall provide all test instrumentation, equipment and accessories necessary for demonstration and putting the equipment into operation. Before commissioning, the Contractor shall submit all necessary calculations of relay settings and coordination curves to the Royal Commission for approval.

5. Upon completion of all testing, the Contractor shall submit 5 copies of a certified report attesting that each test has been performed in accordance with the approved test procedures. The report for each test shall include the name of the person in-charge of the test and the date of performance. All factory and field test reports shall be included in Operation and Maintenance Manuals.

B. Test and Check-Out on Medium Voltage Switchgear and Medium Voltage Motor Controller

1. Check the clearances around the switchgear/ MVMC.

2. Check for the provision of rubber bushing to protect inter-panel control wiring from sharp edges.

3. Check that aluminum gland plates are provided for single core power cables to avoid eddy current losses.

4. Check for smooth operation of breaker during rack-in/rack-out.

5. Check Manual closing/tripping facilities for circuit breaker in service position.

6. Check that bus-bars are properly coupled, tightened as per manufacturers instructions.

7. Check ground bus bar continuity and connection to plant ground grid. The grounding resistance shall comply with recommendations of IEEE 142.

8. Check that all connections and identifications are made in accordance with the relevant schemes. Check all connections for tightness.



9. Perform insulation resistance test on Power and Control wiring and verify that the insulation resistance of ungrounded conductor to ground is a minimum of 10 M.

10. Perform ratio and polarity test on instrument transformer.

11. Perform operational tests on various components, including electrical and mechanical interlocking, local and remote control, local and remote position indication, local and remote alarm indication, local and remote measuring and metering, etc.

12. Perform functional tests on all control circuits using elementary diagram.

13. Set and test all overload relays and protective devices as per relay coordination study data sheets.

14. While testing operation of circuits and controls, operate each control a minimum of 10 times and each circuit continuously for a minimum of hour.

C. Test and Check-Out on Medium Voltage Enclosed Bus

1. Check overall workmanship on field assembly and verify all parts and gaskets in place as per Contract Drawings.

2. Check interior and exterior of equipment to be clean and free of foreign objects.

3. Verify bolted connections are tightened to manufacturers specifications.

4. Perform insulation resistance test on bus.

5. Verify proper phasing.

6. Confirm space heaters are connected and operable.

7. Check ground bus bar continuity and connections to plant ground grid/bus.

8. Inspect finish to confirm paint has been restored as required.

END OF SECTION