Technical Specifications- Isolators

THE KENYA POWER AND LIGHTING COMPANY LIMITED

KENYA ELECTRICITY EXPANSION PROJECT

DISTRIBUTION REINFORCEMENT AND UPGRADE

TECHNICAL SPECIFICATIONS For

Procurement of Isolators, Insulators and Surge Diverters for 66kV, 33kV & 11kV Lines

ICB No: KPLC1/6E/2/A11

(IDA- Credit)

VOLUME II

April 2011

Part 2 Employers Requirements

Part 1 Bidding Procedures

Part 3 Conditions of Contract and Contract Forms

2 Kenya Power and Lighting Co Ltd Section VI Schedule of Requirements Kenya Electricity Expansion Project Technical Specifications

2 Contract XI April 2011 KPLC

Contents SECTION I – GENERAL SPECIFICATIONS1 GENERAL SPECIFICATIONS ..................................................... 3

1 GENERAL SPECIFICATIONS .................................................................................................................................... 4 1.1 SCOPE OF WORKS: .................................................................................................................................................. 4 1.2 DESCRIPTION OF THE PROJECT .......................................................................................................................... 4 1.3 STANDARDS ............................................................................................................................................................ 4 1.4 UNIT OF MEASUREMENT AND LANGUAGE ..................................................................................................... 4 1.5 SERVICE CONDITIONS .......................................................................................................................................... 4 1.6 WORKING STRESS AND EQUIPMENT/APPARATUS DESIGN .................................................................... 6 1.7 BASIC REQUIREMENTS FOR ELECTRICAL EQUIPMENT ............................................................................... 9 1.8 MATERIALS AND WORKMANSHIP ..................................................................................................................... 9 1.9 PROTECTION, CLEANING AND PAINTING ....................................................................................................... 12 1.10 PACKING .............................................................................................................................................................. 13 1.11 DELIVERY ............................................................................................................................................................ 14 1.12 PROGRAMME AND PROGRESS ........................................................................................................................ 14 1.13 EQUIPMENT TESTING AT PLACE OF MANUFACTURE ............................................................................... 14 1.14 PHOTOGRAPHS ................................................................................................................................................... 15

SECTION II - TECHNICAL SPECIFICATIONS ........................................................................................................ 16

2 TECHNICAL SPECIFICATIONS FOR LINE CONSTRUCTION MATERIALS ........................................... 17 2.1 SPECIFICATIONS FOR 66KV THREE POLE DISCONNECTORS ..................................................................... 17 2.2 SPECIFICATIONS FOR 33KV THREE POLE DISCONNECTORS ................................................................ 19 2.3 SPECIFICATION FOR 66KV SURGE ARRESTERS (SURGE DIVERTERS) ..................................................... 22 2.4 SPECIFICATION FOR 33KV SURGE ARRESTERS (SURGE DIVERTERS) ................................................ 25 2.5 SPECIFICATION FOR 66KV LINE POST INSULATORS .................................................................................... 30 2.6 SPECIFICATION FOR 33 AND 11KV COMPOSITE INSULATORS .............................................................. 33 CHARACTERISTICS .................................................................................................................................................... 34 2.7 SPECIFICATIONS FOR 66KV COMPOSITE INSULATORS .......................................................................... 34 2.8 SPECIFICATIONS FOR STAY, STAY INSULATORS AND STAY BLOCKS .................................................... 37 2.9 SPECIFICATION FOR STAY INSULATORS UPTO 66KV .................................................................................. 43 2.10 SPECIFICATION FOR 33 KV EXPULSION FUSE CUT-OUT ........................................................................... 46 2.11 SPECIFICATION FOR 33 KV EXPULSION FUSE HOLDER ............................................................................ 47

3. GUARANTEED TECHNICAL PARTICULARS. ................................................................................................... 50 3.1 PREAMBLE .......................................................................................................................................................... 50

3.1 300MMSQ ALL ALUMINIUM ALLOY CONDUCTOR – NOT REQUIRED .......................................................... 50 3.2 66KV DISCONNECTORS (AIR BREAK SWITCHES) .......................................................................................... 51 3.3 33KV DISCONNECTORS (AIR BREAK SWITCHES) .......................................................................................... 54 3.4 66KV POST INSULATORS ..................................................................................................................................... 57 3.5 66KV COMPOSITE INSULATORS ........................................................................................................................ 58 3.6 33KV COMPOSITE INSULATORS ........................................................................................................................ 58 3.7 66KV SURGE ARRESTORS (DIVERTERS) .......................................................................................................... 59 3.8 33KV SURGE ARRESTORS (DIVERTERS) .......................................................................................................... 60 3.9 66KV 400MMSQ SINGLE CORE XLPE COPPER CABLE – NOT REQUIRED ................................................... 62



Section I – General Specifications



1 GENERAL SPECIFICATIONS 1.1 SCOPE OF WORKS: The contract covers design, supplying and testing before shipment, painting, packing for transport, insuring, shipping, delivering to the port of Kenya, landing, customs clearing, transporting from the port to KPLC stores all materials referred to as ISOLATORS, INSULATORS AND SURGE DIVERTERS FOR 66kV, 33kV & 11kV LINES generally described below. Subsequent paragraphs will give detailed descriptions and requirements as to the plant specified herein. 66kV, 33kV and 11kV overhead lines

• Insulators line hardware materials and fittings • Stays and stay blocks • Insulators Air break switches and fittings

1.2 DESCRIPTION OF THE PROJECT

As described under vol.1 Section VII 1.4 preamble.

1.3 STANDARDS

Ratings, characteristics, tests and test procedures, etc. for the electrical equipment encompassed by this Specification shall comply with the provisions and requirements of the standards of the International Electro-technical Commission (IEC), and or KPLC operational standards unless otherwise expressly stated in Particular Technical Specifications. Where the IEC standards do not fully cover all provisions and requirements for the design, construction, testing, etc. and for equipment and components that are not covered by IEC Recommendations recognized national standards shall be applied.

The latest revision or edition in effect at the time of Bid Invitation shall apply. Where references are given to numbers in the old numbering scheme from IEC it shall be taken as to be the equivalent number in the new five-digit number scheme. The Bidder shall specifically state the Precise Standard, complete with identification number, to which the various equipment and materials are manufactured. The Bid Documents do not contain a full list of standards to be used, as they are only referred to where useful for clarification of the text.

1.4 UNIT OF MEASUREMENT AND LANGUAGE In all correspondence, in all technical schedules and on all drawings prepared by the

Contractor, the metric units of measurement shall be used. On drawings or printed pamphlets where other units have been used, the equivalent metric measurements shall be added. All documents, correspondence, drawings, reports, schedules instructions, and nameplate readings of the equipment shall be in the language stated in the Bid Data sheet.

1.5 SERVICE CONDITIONS

From the geographical condition, the project area is categorized into the tropical climate zone. In choosing materials their finishes, due regard shall be given to the humid tropical conditions under which the plant shall be called upon to work. The contractor shall submit



details of his usual practice which have proven satisfactory and which he recommends for application to the parts of the work, which may be affected by tropical conditions. The materials and finishes used shall be approved by the Employer. All switchgear and control cubicles shall also be rodent and vermin proof.

1.5.1 Environment a) Unless otherwise specifically stated in Particular Technical Specifications or Scope of

Works, any equipment, component and assembly shall be designed for the following service conditions:

Parameter Max Min Ambient air temperature Outdoor +40°C -1°C Indoor +40°C -1°C 24 hour average maximum +30°C -1°C Ambient temperature for cables in the ground +40 °C -1°C Relative humidity 90%

Height above sea level 1800m EMC Class (IEC 61000) Industrial environments Seismic coefficient 1.5 Wind pressure on project area of conductors and cylindrical objects

400 N/m²

Maximum wind pressure on steel members on 1.5 times projected area

820 N/m²

Rainfall conditions Average 800-1700 mm/year Maximum 160mm in 24 hrs Annual mean isokeraunic level Max 180 thunderstorm days Pollution (IEC 60815) Heavy :class II

Wherever any of these maximum or 24 hour average temperatures exceed the normal service condition temperatures of the IEC Recommendations for the relevant equipment, or of such other standard which is approved to be applied, the permissible temperature rises of the IEC Recommendations or the standard shall be reduced by the same amount as the difference between the above figures and the normal service condition temperatures. The Contractor shall guarantee these reduced temperature rises. All air cooled equipment shall be cooled with convection (i.e. without fans) provided other cooling methods are not explicitly allowed for in the specifications.

1.5.2 Acoustics, Noise measurement The equipment shall as far as possible not generate undue vibrations or bothersome noise. Provided nothing else is specified the following requirements shall not be exceeded:

Area of equipment location Maximum noise level dB(A) Machine hall, workshop etc. (one meter from the machine)

85

Office, control room, day room etc 55



Emergency diesel generator (7 meter from engine room)

85

1.5.3 Tropicalization

a) All equipment must be designed for operations in the severe tropic climate conditions and fully comply with climatic aging tests as per IEC 60932-class 2.

b) In choosing materials and their finishes, due regard shall be given to the humid tropical

conditions under which the plant will be called upon to work. Where it is not specifically called for, the contractor shall submit details of his usual practice which have proven satisfactory and which he recommends for application to the parts of the work, which may be affected by tropical conditions. The materials and finishes used shall be approved by the Employer. All switchgear and control cubicles shall also be rodent and vermin proof. Enhanced description.

i. Metals: Iron and Steel are generally to be painted or galvanized as appropriate. Indoor parts may alternatively have chromium or copper-nickel plates or other approved protective finish. Small iron and steel parts (other than rustless steel) of all instruments and electrical equipment, the cores of electromagnets and the metal parts of relays and mechanisms shall be treated in an appropriate manner to prevent rusting.

ii. Screws, Nuts, Springs, Etc.

The use of Iron and steels shall be avoided in instruments and electrical relays wherever possible. Steel screws shall be zinc, cadmium or chromium plated or where plating is not possible owing to tolerance limitations, shall be of corrosion resisting steel. Instrument screws (except those forming part of a magnetic circuit) shall be of brass or bronze. Springs shall be of non-rusting material, e.g., phosphor-bronze or nickel silver, as far as possible.

iii. Rubbers:

Neoprene and similar synthetic compounds, not subject to deterioration due to the climatic conditions, shall be used for gaskets, sealing rings, diaphragms, etc.

TROPICALIZATION TO BE IN COMPLIANCE WITH CLIMATE GRAPH NO. 8 OF THE IEC 721-2-1, TEST B: DRY HEAT IEC 68-2-2 TEST Bd; DAMP HEAT, CYCLIC IEC 68-2-30.

1.6 WORKING STRESS AND EQUIPMENT/APPARATUS DESIGN

1.6.1 General

a) The design, dimensions and materials of all parts shall be such that they will not suffer damage under the most adverse conditions nor result in deflections and vibrations, which might adversely affect the operation of the equipment. Mechanisms shall be constructed to avoid sticking due to rust or corrosion.

b) The equipment and apparatus shall be designed and manufactured in the best and most

substantial and workmanlike manner with materials best suited to their respective purpose and generally in accordance with up-to-date recognized standards of good practice.



c) All parts which will or might have to be dismantled for the purpose of serving or replacement shall be assembled with anti-corrosive fasteners. The type, material and size of all fasteners shall be selected to safely withstand the maximum superimposed direct, alternating, kinetic and all loads induced by workmen when installing or removing the fasteners during the life of the equipment.

d) The equipment shall be designed to cope with 0.15G acceleration of seismology on the

centres of gravity.

e) All equipment shall be designed to minimize the risk of fire and consequential damage, to prevent ingress of vermin, dust and dirt, and accidental contact with electrically energized or moving parts. The plant shall be capable of continuous operation with minimum attention and maintenance in the exceptionally severe conditions likely to be obtained in a tropical climate.

f) Upon request by the Employer complete information regarding the design assumptions,

loading and operating conditions, deflections and unit stresses used in the design shall be provided by the supplier.

g) The Contractor shall be deemed to have examined the specification and drawings herewith,

and unless stated specifically to the contrary in the schedule of proposed conditions and /or deviations from the specification to have concurred with the design and layout of the applicable project features as being sufficient to insure reliability and safety in operation, freedom from undue stresses, adequate drainage and other essentials for a satisfactory working plant.

1.6.2 Strength and quality

a) All steel castings and weldings shall be stress-relieved by heat treatment before machining, and castings shall be stress-relieved again after repair by welding.

b) Liberal factors of safety shall be used throughout, especially in the design of all parts subject

to alternating stresses or shocks. 1.6.3 Design data High and medium voltage plant and equipment

The rating and design criteria for the HV and MV plant and equipment shall be as follows:

Item Parameters SYSTEM VOLTAGE 66 kV 33 kV 11 kV 1 System 50 Hz, 3 phase 2 Neutral point earthing Solid earthed 3 Nominal voltage of networks 66 kV 33 kV 11 kV 4 Highest system voltage as defined by

IEC-60038 72.5 kV 36 kV 12 kV

5 Short circuit and earth fault current, symmetrical r.m.s. value (min breaking current) not less than

25 kA 25 kA 25 kA

6 Thermal short-circuit current, 3 second not less than

25kA 25 kA 25kA

7 Dynamic peak current (min making 63 kA 63 kA 63 kA



Item Parameters SYSTEM VOLTAGE 66 kV 33 kV 11 kV

current)not less than 8 Rated current of busbars and bus

coupler if not given in Scope of Works, for each individual substation

1250 A 1250 A 1250 A

9 Minimum rated current of isolating switches and circuit breakers if not given in Scope of Works

800 A 800 A 630 A

10 Insulation level according IEC 60071: 10a Switching surge withstand voltage Phase-to-earth N/A N/A N/A N/A Longitudinal impulse component of

combined test N/A N/A N/A

10b Lightning impulse withstand voltage (1.2/50 m/s kVpeak) at 1000m a.s.l

325 kV 170 kV 75 kV

10c Test voltage at power frequency 1 min dry and wet. To earth and between phases at 1000m a.s.l

140 kV 70 kV 28 kV

11 For the design and erection of the conductors in the switchyard the following minimum distances shall be observed

11a Phase to earth [mm] 700 500 500 11b Phase to phase [mm] 790 435 250 11c Busbars phase to phase [mm] 1250 11e Height to live parts above ground [mm] 3500 2900 2900 11f Height to live parts above ground at

transformer transport routes [mm] 5000

12g Lowest part of insulators above ground [mm]

2 500

12 Maximum temperature rise of conductors above ambient temperature (40 ºC)

40 ºC

13 Maximum wind pressure on conductors and cylindrical objects

400 N/m2

14 Maximum wind pressure on flat surfaces

820 N/m2

15 Minimum nominal creepage distance as defined in IEC 60815, Table II

25 mm/kV (inland area) 31 mm/kV (in coast and industrial area)

Note 1) Ref IEC 60038) Note 2) For all current carrying parts the permissible short circuit duration shall be at least 1 second. Indoor equipment shall be arch tested in accordance with IEC 60298 amendment 2. The dynamic or momentary short circuit current on which the equipment design shall be based shall be computed by multiplying the r.m.s. value of the symmetrical short circuit current by the factor 1.8 x 2 .



Note 3) Ref IEC 60071) All High and Medium Voltage equipment shall be designed for installation at 2200 m above sea level. IEC 60071 shall apply with the specified correction factor for the altitude above sea level. 1.7 BASIC REQUIREMENTS FOR ELECTRICAL EQUIPMENT

All materials supplied under this Contract shall be new and of the best quality and of the class most suitable for working under the conditions specified. They shall withstand the variations of temperature and atmospheric conditions arising under working conditions without distortion deterioration or undue stresses in any parts and also without affecting the suitability of the various parts of the Works for which they were designed. The Plant shall be designed for a lifetime of 40 years. Equipment with a shorter life cycle shall be identified and so arranged that they are easy to replace.

1.7.1 Corona and radio interference

a) Switchgear shall be electrically designed to avoid local corona formation and discharge likely to cause radio interference.

b) The design of all line conductor fittings, insulator fittings, etc. shall avoid sharp corners or

projections which would produce high electrical stress in normal operation.

c) The design of adjacent metal parts and melting surfaces shall be such as to prevent corrosion of the contact surfaces and to maintain good electrical contact under service conditions.

d) Particular care shall be taken during manufacture of conductors and fittings and during

subsequent handling to insure smooth surface free from abrasion. 1.7.2 Insulators and fittings

a) All porcelain insulators and bushings for outdoor equipment shall be brown glazed. The resin insulators for indoor equipment may be of the inherent colour of the resin. All fittings shall be malleable iron hot-dipped galvanized alloy.

b) All the insulators and bushings shall have impressed thereon, before firing the glaze, the

name, initial or trade mark of the manufacturer, the year of manufacture and the mechanical strength.

1.8 MATERIALS AND WORKMANSHIP 1.8.1 General

a) Materials shall be new; the best quality of their respective kinds and such as is usual and suitable for work of like character. All materials shall comply with the latest issues of the specified standard unless otherwise specified or permitted by the Employer.



b) Workmanship shall be of the highest class throughout to ensure reliable and vibrations free Operations. The design, dimensions and materials of all parts shall be such that the stresses to which they may be subjected shall not cause distortion, undue wear, or damage under the most severe conditions encountered in service.

c) All parts shall conform to the dimensions shown on and shall be built in accordance with

approved specifications. All joints, datum surfaces and meeting components shall be machined. All machined finished shall be shown on the drawings. All screw, bolts, studs and nuts and threads for pipe shall conform to the latest standards of the International Organization for Standardization covering these components and shall all conform to the standards for metric sizes. The supplier shall never incorporate any standards or size system by his own account, regardless of that accepted and incorporated in this Contract.

d) All materials and works that have cracks, flaws or other defects or inferior workmanship will

be rejected by the Employer. All defective materials shall be promptly removed from the site by the supplier.

1.8.2 Standard Specifications The design, materials, manufacture, testing, inspection and performance shall, unless

otherwise specified in the Special requirements of these Specifications, conform to the authorized standards of the International Electro technical Commission (IEC) or equivalent national standards in additional to KPLC Operational procedures. The supplier shall include a statement of the standards, intended to be used.

1.8.3 Assembly Necessary items of equipment shall be assembled in the factory prior to shipment and routine

tests shall be performed by the contractor as may be required to demonstrate to the satisfaction of the Employer the adequacy of equipment and its component parts. All tests should simulate normal operating conditions as closely as possible. All dismantled parts shall be properly match marked and doweled to ensure correct assembly in the field.

1.8.4 Casting

a) Casting shall be true to pattern, of workmanlike finish and of uniform quality and condition, free from blowholes, porosity, hard spots, shrinkage defects, cracks or other injurious defects, shall be satisfactorily cleaned for their intended purpose.

b) Major defect on castings shall not be repaired, plugged, or welded without permission of

the Employer. Such permission will be given only when the defects are small and do not adversely affect the Strength, use or merchantability of the castings. The Employer shall give the distinction between major and minor defects. Excessive segregation of impurities or alloys at critical points in a casting will be a cause for its rejection. The largest fillets compatible with the design shall be incorporated wherever a change in section occurs. All castings shall be stress-relieved before machining and again after repair by welding.

c) Plates to be joined by welding shall be accurately cut to size and rolled by pressure to the

proper curvature, which shall be continuous from the edges. Flattening in the curvature along the edges with correction by blows will not be allowed. The dimensions and shape



of the edges to be jointed shall be such as to allow thorough fusion and complete penetration, and the edges of plates shall be properly formed to accommodate the various welding conditions.

1.8.5 Forging

a) The ingots from which the forgings are made shall be cast in metal moulds. The workmanship shall be first-class in every respect and the forgings shall be free from all defects affecting their strength and durability, including seams, pipes, flaws, cracks, scales, fins, porosity, hard spots, excessive non-metallic inclusions and segregations.

b) The largest fillets compatible with the design shall be incorporated wherever a change in

section occurs. All finished surfaces of forgings shall be smooth and free from tool marks.

c) The forging shall be clearly stamped with the heat number in such locations to be readily

observed when the forging is assembled in a completed unit. 1.8.6 Welding

a) Wherever welding is specified or permitted, a welding process, including stress relieve treatment as required if necessary, conforming to an appropriate and widely recognized professional standard shall be used.

b) Plates to be joined by welding shall be accurately cut to size and rolled by pressure to the

proper curvature, which shall be continuous from the edge. Flattening in the curvature along the edges with correction by blows will not be allowed. The dimensions and shape of the edges to be jointed shall be such as to allow through fusion and complete penetration, and the edges of plates shall be properly formed to accommodate the various welding conditions.

c) The surfaces of the plates adjacent to the edges to be welded shall be thoroughly cleaned

of all rust, grease and scale to bright metal. All important welding shall be stress-relieved by heat treatment before machining.

1.8.7 Galvanizing

a) Unless specifically mentioned to the contrary, iron and steel shall be galvanized in the factory after fabrication. The zinc coating shall be uniform, clean, smooth and as free from spangle as possible. Galvanizing shall be applied by the hot dip process for all parts other than steel wires. All steel wires shall be galvanized by a recognized trade standard.

b) The minimum quantities of zinc coating shall be 350 gram/sq. metre for bolts and nuts

and 550 gram/sq. Metre for all other parts except steel wires, unless otherwise specified in the Contract Documents. The uniformity of zinc coating, tested by dipping surface shall be exposed until the surface has been dipped four times for bolts and nuts, and six times for all parts.



c) The preparation for galvanizing and the galvanizing itself shall not distort or adversely affect the mechanical properties of the materials.

d) Special treatment during galvanizing to prevent the formation of “White rust” during

shipment or storage is required. The Bidder shall state in his Tender the treatment to be used.

1.8.8 Colour standard

The final colour of each item shall be as described under each item. 1.8.9 Nameplate

a) To facilitate operation and maintenance it is very important that all equipment e.g., Outdoor/indoor Switchgear, valves, instruments, switches, pipeline, etc., shall be clearly identified by nameplates showing the function and proper use of each item. Such identification shall be in English and must be intelligently and carefully designed to minimize errors and to avoid maloperation in operation or maintenance.

b) The nameplates shall be permanently legible, clearly worded, weather proof when outdoors

and securely mounted in conspicuous and logical locations.

c) A table showing materials, dimensions, location, mounting and wording shall be submitted to the Employer for approval.

1.9 PROTECTION, CLEANING AND PAINTING

1.9.1 Embedded steelwork

All parts to ultimately be buried in concrete shall be cleaned and protected before leaving the manufacturer’s plant by cement wash or other approved method. Before being installed they shall be thoroughly desiccated and cleared of all rust and adherent matter, or be treated according to a method approved by the Employer. Such cleaning or treatment shall not detrimentally affect the strength or final operation and function of the equipment.

1.9.2 Steel exposed to atmosphere

a) All machined parts or bearing surfaces shall be cleaned and protected from corrosion before leaving the manufacturer’s plant by the application of an approved rust preventive coating, or a peelable plastic film. Where the latter is impracticable, such parts shall be heavily covered with high melting point grease.

b) All parts, other than machined parts, which will be exposed after erection shall be

thoroughly cleaned and galvanized or given with two coats of best quality approved primer and one coat of best quality approved finish paint before leaving the manufacturer’s plant. All outside panel surfaces shall be primed, filed where necessary, and given not less than two coats of synthetic undercoat. The finishing coat for the outdoor and indoor installations shall be gloss paint.



c) All steel surfaces, which are in permanent contact with oil, shall be given three coats of approved oil resistant.

d) No painting or protection is required for finished or unfinished stainless steel

parts.

e) The final colour of all equipments, frames for meters and relays, and switch handle shall be as described under each particular item.

f) The humid and tropical conditions shall be taken into account on selection of the

paints and painting procedure. 1.10 PACKING

a) Each item shall be packed properly or protected for shipment from the place of manufacture to the site.

b) Each crate of package shall contain a packing list in a waterproof envelope and a copy

in triplicate shall be forwarded to the Employer prior to dispatch. All items of material shall be clearly marked for easy identification against the packing list.

c) All cases, packages, etc, shall be clearly marked on the outside to indicate the total

weight, to show where the weight is bearing and the correct position of the slings and shall bear an identification mark relating them to the appropriate shipping documents.

d) Cases, which cannot be marked as above, shall have metal tags with the necessary

marking on them. The metal tags shall be securely attached to the package with strong steel wire or equivalent.

e) Long pieces of steel angles shall be packed in bundles and properly tied together by

an approved method and care taken to ensure that they are robust and not of excessive length and weight for handling in transit.

f) Short pieces of steel angles and steel plates shall be bolted or wired together through

holes and packed in stout timber cases.

g) Bolts, nuts, washers and fillers shall be bagged in sealed vinyl and packed in steel cans. The cans shall bear the contents and be crated together.

h) Packing together of components of dissimilar metals shall not be acceptable.

i) Conductors and overhead earth wire shall be packed on drums stoutly constructed of

good quality wood. Drums shall be securely battened around the perimeter to give maximum protection to the conductor and the earth wire and correct direction of rolling indicated with an arrow in a manner not easily removable.

j) The first layer of conductors or earth wire on drums shall be secured to the hub in

manner avoiding damage to subsequent layers.

k) All drums shall be protected from deterioration on site by termite or fungus attack by an approved impregnation treatment at the works before dispatch.



l) The Employer shall reserve the right to inspect and approve the equipment and the

packing before the items are dispatched. The supplier shall be entirely responsible for ensuring that the packing is suitable for transit and such inspection will not relieve the supplier from responsibility for any loss or damage due to faulty packing.

(a) Consignee: NAME OF SUPPLIER (b) Name of Project: SUPPLY OF ISOLATORS, INSULATORS AND SURGE

DIVERTERS FOR 66KV, 33KV & 11KV LINES (c) Contract No.: KPLC1/6E/2/A11 (d) Port of destination: KPLC, NAIROBI SOUTH STORES (e) Item Number, if applicable,

Package number in sequence, and quantity per package: ……………………………………………….

(f) Description of Contents: ………………………………………………

Net and gross weight, cubic measure: ………………………………… The shipping mark is finally subject to the Employer’s approval.

1.11 DELIVERY

a) The Supplier shall deliver all materials supplied under the Contract to the site in adequate time for its according to the Schedule.

b) Each delivery notification shall include a complete shipping list of the contents of each

package to be delivered and shall indicate the anticipated date of delivery and the serial number for each component to be used for identification and evidence of the insurance cost arranged for it.

1.12 PROGRAMME AND PROGRESS

a) Within 21 days after the date of signing the contract agreement, the Contractor shall prepare his detailed program in a Software form covering the design, manufacture and delivery of the Works, in sufficient detail to define the various sections of the Works. A Soft and hard copy shall be submitted to the Employer for approval.

b) Upon approval of the programme by the Employer, it should thereafter be referred to as

the approved detailed Construction Program and shall become a part of the Contract.

c) Regular Monthly progress reports shall be provided by the supplier, indicating the actual state of progress of all items during the course of manufacture in the form given by the Employer.

1.13 EQUIPMENT TESTING AT PLACE OF MANUFACTURE

a) The manufacturers shall be responsible for performing or for having performed all the required tests specified under the specification for all the equipment. Bidders shall confirm



the manufacturer’s capabilities in this regard when submitting tenders. Any limitations shall be clearly specified.

b) Tender documents shall be accompanied by copies of Type test and Routine test reports &

certificates for similar rated equipment for the purpose of tender evaluation. Type test reports & certificates shall be certified by the National Standards and Testing Authority (NSTA) of the country of origin. Where a body other than NSTA is used to certify the type-test reports, a copy of the certificate of accreditation shall be attached. Current contact information of the testing and certification authority shall be provided.

c) Upon completion of the manufacturing process, routine tests shall be carried out as per the

respective standards of each equipment and the results endorsed by the NSTA of the country of manufacture.

d) The Contractor shall arrange for the Employer’s staff members to witness tests of major items

of equipment in the manufacturer’s plant as follows: (1) As per schedule 3 in Vol 1

e) The equipment mentioned above shall be subjected to inspection by two KPLC Engineers or

her representative at place of manufacture for 5 days per equipment and all routine tests and other tests specified under each specification carried out in their presence. KPLC representatives shall approve shipment of the equipment if they are satisfied that the requirements of the specification are fully met. The supplier shall quote separately as in Vol 1 for these inspections. The full cost of the visit, including air tickets, manufacturer’s local transportation and accommodation shall be borne by the contractor.

1.14 PHOTOGRAPHS The Contractor shall keep photographic records of the progress of each phase of the work. The determination of each particular phase shall be agreed upon between the contractor and the employer after contract signing and as work progresses. Upon completion of the work, the Contractor shall submit three sets of colour photographs or a CD with explanatory description adequately edited in book form to the Employer’s satisfaction.



Section II - Technical Specifications



2 TECHNICAL SPECIFICATIONS FOR LINE CONSTRUCTION

MATERIALS 2.1 SPECIFICATIONS FOR 66KV THREE POLE DISCONNECTORS

2.1.1 SCOPE

a) This specification is for 66kV, 1250 Amps Isolator for isolation of substation apparatus

b) This specification covers the following isolators.

• 66 kV isolator without earth switch

• 66 kV isolator with earth switch

2.1.2 REFERENCES

The following documents were referred to during the preparation of this specification, and may be referred to in case of conflict; the provision of this specification shall take precedence.

Unless otherwise specified, the latest revision, edition and amendments shall apply

• IEC 60129: Alternating current disconnectors (isolators) and earthing switches.

• BS 729 Hot dip galvanised coating on iron and steel articles.

2.1.3 SERVICE CONDITIONS

As stated in clause 1.5 2.1.4 CONSTRUCTION

a) The isolator shall be vertical or horizontal opening, single break or double centre break rotating post type for use on a 66kV, 50 Hz, three phase system.

b) The mechanism box shall be equipped with a 240V AC space heater controlled by a

Hygrostat with variable humidity and temperature control settings. c) The isolator shall be complete with supporting base, phase coupling details, operating

rod, unions and guides.

d) The operating mechanism shall be provided with a universal joint to allow for a reasonable degree of out-of alignment of the operating rod.

e) The supporting underbase shall be hot dip galvanised steel as per the requirement of

BS 729.



f) The Isolator shall be provided with a motor operating device interlocked with the manual operating mechanism. The motor operating device shall be provided with a locking device which shall be strong and durable enough for mechanically locking, under the open or closed condition of the Isolator. The Locking device shall be lockable by a padlock and the operating condition of the locking device shall be easily recognizable from the outside.

g) The underbase shall be suitable for mounting on a steel structure.

h) All the three switches shall be arranged so that the phase units are mounted

independently and then finally interconnected with coupling tubes so as to ensure simultaneous operation of all switches by drive rods and operating handle both manual and motor-drive operation. Motor operating voltage shall be 110volts d.c.

i) The operating mechanism shall be fixed at the base frame, in a weather proof, vermin

proof and dust proof housing. The degree of protection shall be class IP 54 according to IEC 144.

j) The control box of the motor operating device shall be vermin, dust and moisture

proof (Protection class IP54) and provided with suitable heaters to prevent moisture condensation.

k) The operating mechanism shall be provided with off/local/remote selector switch.

The selection of local operation shall inhibit the operation from any remote source.

l) Auxilliary switches, shall be provided for electrical interlocks with a circuit breaker.

m) The isolator shall be designed such that in fully open position, it shall provide adequate electrical isolation between the contacts on all the three switches.

n) The Isolator shall be operable by one person safely and smoothly.

o) A set of at least 5 No and 5NC potential free contacts shall be provided for indication

and interlocking and shall be wired to a terminal block in the housing

p) All current carrying parts be made of electrolytic high conductivity material with switch contacts silver plated.

q) The isolator with the earth switch shall consist of a hinged type earth switch fixed at

the base frame. The earth switch shall have the same rating as the isolator.

r) Separate hand operated handle shall be provided for the Isolator and the Earth Switch. Mechanical as well as electrical interlocking (e.g coil) shall be provided for the Isolator/Earth Switch assembly so that any switch cannot be closed when the other switch is in closed position.

s) The isolator shall be provided with a padlocking facility such that it can be locked in

either OPEN or CLOSED position.

t) The mechanism box shall be provided with locking facilities.



u) The Isolator shall have a CLOSED and OPEN mechanical indicators next to the operating handle for status indication of the isolator. Status indications shall also be provided for the earth switch.

2.1.5 RATING

The ratings of the isolator, including its operating devices and auxiliary equipment shall be as under.

Highest voltage of equipment 72 kV Rated lightening impulse withstand voltage 450 kV Rated Power frequency withstand voltage 185 kV Rated frequency 50 Hz Rated normal current 1250 Amps Rated short time withstand current for 3 seconds 31.5 kA Earth switch Rated short time withstand current

for 3 seconds 31.5KA

Minimum creepage distance of Insulators 1800mm Auxiliary D.C Voltage for controls 110 V d.c. Motor charging supply 110V dc/ac Auxiliary A.C Voltage for heater 240 V, 50 Hz

2.1.6 TESTS

See clause 1.16

a) The isolator shall be inspected and routine tested in accordance with the requirement

of IEC 60129. b) The followings are the tests:

Routine tests

• Assembly and operation test • Measurement of resistance between main terminals • 1 minute Power frequency voltage tests • 1 minute power frequency voltage tests on control and auxiliary circuits • Temperature rise test

Type tests (Similar rated 66kv isolators) • Mechanical endurance test • Impulse voltage test • Short circuit circuit current test

2.2 SPECIFICATIONS FOR 33KV THREE POLE DISCONNECTORS

2.2.1 SCOPE

a) This specification is for 33kV, 800 Amps Isolator for isolation of substation apparatus and line isolation .

b) This specification covers the following isolators.



• 33kV isolator without earth switch

• 33KV isolator with earth switch

2.2.2 REFERENCES

The following documents were referred to during the preparation of this specification, and may be referred to in case of conflict; the provision of this specification shall take precedence.

Unless otherwise specified, the latest revision, edition and amendments shall apply

• IEC 60129: Alternating current disconnectors (isolators) and earthing switches.

• BS 729 Hot dip galvanised coating on iron and steel articles.



a) The isolator shall be vertical or horizontal opening, single break or double centre break rotating post type for use on a 33kV, 50 Hz, three phase system.

b) The mechanism box shall be equipped with a 240V AC space heater controlled by a

Hygrostat with variable humidity and temperature control settings. c) The isolator shall be complete with supporting base, phase coupling details, operating

rod, unions and guides.

d) The operating mechanism shall be provided with a universal joint to allow for a reasonable degree of out-of alignment of the operating rod.

e) The supporting underbase shall be hot dip galvanised steel as per the requirement of

BS 729.

f) The Isolator shall be provided with a manual operating mechanism with a locking device. The Locking device shall be lockable by a padlock and the operating condition of the locking device shall be easily recognizable from the outside.

g) The underbase shall be suitable for mounting on a steel structure.

h) All the three switches shall be arranged so that the phase units are mounted

independently and then finally interconnected with coupling tubes so as to ensure simultaneous operation of all switches by drive rods and operating manual handle.



i) The operating mechanism shall be fixed at the base frame, in a weather proof, vermin proof and dust proof housing. The degree of protection shall be class IP 54 according to IEC 144.

j) Auxilliary switches, shall be provided for electrical interlocks with a circuit breaker.

k) The isolator shall be designed such that in fully open position, it shall provide

adequate electrical isolation between the contacts on all the three switches.

l) The Isolator shall be operable by one person safely and smoothly.

m) A set of at least 5 No and 5NC potential free contacts shall be provided for indication and interloacking and shall be wired to a terminal block in the housing

n) All current carrying parts be made of electrolytic high conductivity material with

switch contacts silver plated.

o) The isolator with the earth switch shall consist of a hinged type earth switch fixed at the base frame. The earth switch shall have the same rating as the isolator.

p) Separate hand operated handle shall be provided for the Isolator and the Earth Switch.

Mechanical as well as electrical interlocking (e.g coil) shall be provided for the Isolator/Earth Switch assembly so that any switch cannot be closed when the other switch is in closed position.

q) The isolator shall be provided with a padlocking facility such that it can be locked in

either OPEN or CLOSED position.

r) The mechanism box shall be provided with locking facilities.

s) The Isolator shall have a CLOSED and OPEN mechanical indicators next to the operating handle for status indication of the isolator. Status indications shall also be provided for the earth switch.

2.2.5 RATING

The ratings of the isolator, including its operating devices and auxiliary equipment shall be as under.

Rated lightening impulse withstand voltage 170 kV Rated Power frequency withstand voltage 70kV Rated frequency 50 Hz

Highest system voltage at 1200m altitude 36kv Highest equipment voltage To be stated

Rated normal current Line /S/station 800 Amps Rated short time withstand current for 3 seconds 25 kA Earth switch Rated short time withstand current for 3

seconds 25KA

Minimum creepage distance of Insulators 25 mm/kv Auxiliary A.C Voltage for heater 240 V, 50 Hz



2.2.6 TESTS

See clause 1.16

a) The isolator shall be inspected and routine tested in accordance with the requirement

of IEC 60129. b) The followings are the tests:

Routine tests • Assembly and operation test • Measurement of resistance between main terminals • 1 minute Power frequency voltage tests • 1 minute power frequency voltage tests on control and auxiliary circuits • Temperature rise test

Type tests (Similar rated 33kv isolators) • Mechanical endurance test • Impulse voltage test • Short circuit circuit current test

2.3 SPECIFICATION FOR 66KV SURGE ARRESTERS (SURGE DIVERTERS)

2.3.1 SCOPE

This specification is for metal-oxide type surge arresters without spark gaps for a.c. system operated at a nominal voltage of 66kV 50Hz.

2.3.2 REFERENCES

ISO 1461: Metallic Coatings – Hot dip galvanized coatings on fabricated

ferrous products – Requirements. IEC 60099-4: Metal-oxide surge arresters without gaps for a.c. systems. IEEE Std C62.22: Guide for the application of metal-oxide surge arresters for

alternating current systems.

2.3.3 TERMS AND DEFINITIONS

For the purpose of this specification the definitions given in the reference standards shall apply.

2.3.4 REQUIREMENTS

2.3.4.1 SERVICE CONDITIONS

2.3.4.1.1 As stated in clause 1.5



2.3.4.1.2 The surge arrestor shall be connected between phase and earth to system that is without continuous aerial earth wire and with the following characteristics:

System Highest Voltage 72kV System Frequency 50Hz

Maximum Duration of Earth Fault 3 seconds Power frequency withstand voltage 140kV Lightning impulse withstand voltage 325kVp

2.3.4.2 DESIGN AND CONSTRUCTION

2.3.4.2.1 The surge arrester shall be designed and constructed to IEC 60099-4 and the requirements of this specification.

2.3.4.2.1 The surge arrester shall be metal-oxide type without spark gaps. It shall be

suitable for over voltage protection of sub-transmission networks. 2.3.4.2.2 The metal-oxide used shall be of quality to ensure thermal stability under

service duty of the surge arrester. 2.3.4.2.3 The arrester shall be single column; self supported and shall be installed

between phase and earth. 2.3.4.2.4 The completed surge arrester shall be housed in a spiral type solid core

porcelain insulator (brown colour). The porcelain housing shall be dimensioned to provide a leak free interface with the end caps. The housing shall withstand the lighting impulse voltage of the arrester.

2.3.4.2.5 The surge arrester shall be sealed (end caps) with a controlled permanent

seal to ensure no moisture absorption or deterioration of the metal-oxide element of the surge arrester.

2.3.4.2.6 The surge arrester shall be designed and constructed in a manner so as to

prevent explosive shattering of the housing in the event of the arrester failure. The surge arrester shall be fitted with a pressure relief/disconnector device, which shall have an indicator of operation visible from ground level.

2.3.4.2.7 Each surge arrester shall be complete with a surge counter. 2.3.4.2.8 The surge arrester shall be supplied complete with fixing accessories and

fitted with pad type clamp connectors suitable for both copper and aluminium bus bar tubes of up to 76.2mm diameter.

The surge arrester shall be complete with an insulated pedestal. The mounting shall be on a pitch circle diameter (p.c.d.) of 127mm.

2.3.4.2.9 he steel plates or straps and all ferrous parts shall be hot dip galvanized in accordance to ISO 1461.



2.3.4.3 RATING

The rating of the surge arrester shall be as indicated below:-

Description Requirement Site Conditions Areas inland, cities, suburbs of cities and

altitude of 2000m above sea level. System Rated Voltage and Frequency 66 kV, 50Hz Highest System Voltage 72.6 kV Nominal discharge current 10 kA Line discharge class 2 Continuous operating voltage 42kV Creepage distance of insulator 1800mm External insulation lightning impulse withstand voltage (peak) at 1000m a.s.l.

450kVp (so as to suit service conditions specified)

External insulation power frequency withstand voltage (wet) at 1000m a.s.l.

185kV rms (so as to suit service conditions specified)

Internal insulation (impulse & power frequency withstand voltages)

325kVp, 140kV rms

2.3.4.4 TESTS AND INSPECTION

Refer to clause 1.16 2.3.4.4.1 Type tests and routine/sample tests shall be done in accordance to IEC

60099-4, ISO 1461 and the requirements of this specification. It shall be the responsibility of the manufacturer to perform or to have performed all the tests specified.

2.3.4.4.2 Certified true copies of previous Type Test Certificates and Type Test

Reports by the relevant International or National Testing/Standards Authority of the country of manufacture (or ISO/IEC 17025 accredited laboratory) shall be submitted with the offer for evaluation (all in English Language). A copy of accreditation certificate for the laboratory shall also be submitted. Any translations of certificates and test reports into English language shall be signed and stamped by the Testing Authority.

Copies of type test reports (as per IEC 60099-4) to be submitted shall include the following;

2.3.4.4.3 Insulation withstand tests on the arrester housing; 2.3.4.4.4 Residual voltage tests; 2.3.4.4.5 Long duration current impulse withstand test; 2.3.4.4.6 Operating duty tests; 2.3.4.4.7 Tests of arrester disconnectors. 2.3.4.4.8 Routine/sample test reports for the surge arresters to be supplied shall be

submitted to KPLC for approval before shipment/delivery of the goods. KPLC Engineers (2) shall witness tests at the factory before shipment.



Tests to be witnessed by KPLC Engineers at the factory shall include the following:

2.3.4.4.9 Measurement of reference voltage; 2.3.4.4.10 Residual voltage test; 2.3.4.4.11 measurement of power frequency voltage on the complete arrester; 2.3.4.4.12 lightning impulse residual voltage on the complete arrester; 2.3.4.4.13 partial discharge test.

2.3.4.4.14 Upon receipt of the surge arresters, KPLC will inspect them and may

perform or have performed any of the relevant tests in order to verify compliance with the specification. The manufacturer shall replace without charge to KPLC, surge arresters which upon examination, test or use fail to meet any or all of the requirements in the specification.

2.3.4.5 MARKING, LABELLING, INSTRUCTIONS AND PACKING

2.3.4.5.1 The following information shall be marked indelibly and legibly on a nameplate attached permanently to each surge arrester:

a) Continuous operating voltage; b) Rated voltage; c) Rated frequency; d) The manufacturer’s name, type and identification of the complete arrester; e) The year of manufacture; f) Serial number; g) Line discharge class and current. All marking shall be by engraving (or superior method).

2.3.4.5.2 A set of three (3) original installation and technical manuals for the surge arresters shall be submitted with the equipment. Details on the pressure relief and surge counter shall also be submitted.

2.3.4.5.3 The surge arresters shall be packed in wood crates which are reinforced

and held closed by external steel wire bindings. Each crate shall be internally braced to permit stacking and the steel wire bindings shall be designed to keep the crate firmly closed and permit easy and rapid opening at time of installation.

The crates shall then be stacked on sturdy wood pallet. The assembly shall be held tightly in place with steel bands and protected against moisture by a complete covering of heat-shrinkable polyethylene film.

2.4 SPECIFICATION FOR 33KV SURGE ARRESTERS (SURGE DIVERTERS) 2.4.1 SCOPE

This specification is for metal-oxide type surge arresters without spark gaps for a.c. system operated at a nominal voltage of 33kV 50Hz.



The specification also covers inspection and test of the surge arresters as well as schedule of Guaranteed Technical Particulars to be filled, signed by the manufacturer and submitted for tender evaluation (together with required documents). The specification stipulates the minimum requirements for 33kV surge arresters acceptable for use in the company and it shall be the responsibility of the Manufacturer to ensure adequacy of the design, good workmanship and good engineering practice in the manufacture of the surge arresters for KPLC. The specification does not purport to include all the necessary provisions of a contract

2.4.2 REFERENCES

The following standards contain provisions which, through reference in this text constitute provisions of this specification. Unless otherwise stated, the latest editions (including amendments) apply. ISO 1461: Metallic Coatings – Hot dip galvanized coatings on fabricated ferrous

products – Requirements

IEC 60099-4: Metal-oxide surge arresters without gaps for a.c. systems


For the purpose of this specification the definitions given in the reference standards shall apply.

2.4.4 REQUIREMENTS

2.4.4.1 SERVICE CONDITIONS

Refer to Clause 1.5

2.4.4.1.1 The surge arrestor shall be connected between phase and earth to system that

is without continuous aerial earth wire and with the following characteristics:

System Highest Voltage 36kV System Frequency 50Hz Maximum Duration of Earth Fault 3 seconds Power frequency withstand voltage 95kV Lightning impulse withstand voltage 200kVp

2.4.4.1.2 The type of equipment to be protected includes transformers (directly

connected to a line or via cable), equipment in substations and cables. The earthing at the transformer is solid earth.

2.4.4.2 DESIGN AND CONSTRUCTION



The surge arrester shall be designed and constructed to IEC 60099-4 and the requirements of this specification. It shall be suitable for overvoltage protection of distribution networks. The metal-oxide used shall be of quality to ensure thermal stability under service duty of the surge arrester.

The arrester shall be single column type, self supported and be installed between phase and earth. The housing of the surge arrester shall be made of high quality silicone rubber of the following minimum properties:

a) hydrophobic b) insensitivity to ultra-violet radiation c) excellent tracking resistance d) excellent mechanical impact, abrasion and shear resistance e) excellent long-term stability and resistance to ageing under climatic and

electrical stresses. The surge arrester shall be sealed (end caps) with a controlled permanent seal to ensure no moisture absorption or deterioration of the metal-oxide element of the surge arrester. The surge arrester shall be designed and constructed in a manner so as to prevent explosive shattering of the housing in the event of the arrester failure. The surge arrester shall be supplied complete fitted with a mechanical fault indicator. Details on the operation shall be submitted with the offer and during delivery. The surge arrester shall be supplied complete with mounting bracket, fixing accessories and clamp connector suitable for both copper and aluminium conductors of up to 18.3mm diameter. All parts shall be corrosion resistant.

The mounting brackets for distribution class surge arresters shall be suitable for both horizontal and vertical mounting on a steel crossarm (U-channel). Station class surge arrester in porcelain housing, when required, shall be suitable for pedestal mounting with pitch circle diameter of 76mm.

All steel plates or straps and all ferrous parts shall be hot dip galvanized to ISO 1461.

2.4.4.3 RATING

The rating of the surge arrester shall be as indicated below:-

System Information Requirement

Highest Voltage of Equipment (Um) 36.0kV Basic Insulation Level (BIL) 200kV Maximum altitude of installation (a.s.l.) 2200m Neutral system earthing solid Maximum ambient temperature 40°C Power Frequency 50Hz



Electrical data

Applicable Standard IEC 60099-4 Rated voltage (Ur) 30.0kV Maximum continuous operating voltage (Uc / MCOV) 24.0kV Nominal discharge current (In, 8/20 µs) 10kA Line discharge class 2 ADDITIONAL INFORMATION TO BE DECLARED BY MANUFACTURER Long duration impulse current withstand (2 ms) ≥ 500A (Typical) High current impulse withstand (4/10 µs) 100kA (Typical) Rated short circuit current (0,2 s) 65.0kA (Typical) Maximum residual voltage at : 10 kA 1/2 µs ≤ 88kV (Typical) 5 kA 8/20 µs ≤ 77kV (Typical) 10 kA 8/20 µs ≤ 83kV(Typical) 20 kA 8/20 µs ≤ 93kV(Typical) 40 kA 8/20 µs ≤ 106kV (Typical) 500 A 30/60 µs ≤ 64kV(Typical) 1 kA 30/60 µs ≤ 67kV(Typical) 2 kA 30/60 µs ≤ 70kV(Typical) Temporary overvoltage for 1 s ≥ 34kV Temporary overvoltage for 10 s ≥ 32kV Energy discharge capability - thermal ≥ 5.00kJ/kVr Energy discharge capability - impulse ≥ 2.60kJ/kVr Power Frequency withstand voltage (1min, wet), arrester complete

≥ 86.0kV

Lightning Impulse withstand voltage (1.2/50 µs), arrester complete

≥ 184kV

Mechanical data

Minimum creepage distance ≥ 900mm Cantilever load, dynamic ≥ 1500N(Typical) Construction Cage design Housing Silicone rubber directly

molded onto MOV blocks

2.4.5 TESTS AND INSPECTION

2.4.5.1 Type tests and routine/sample tests shall be done in accordance to IEC 60099-4, ISO

1461 and the requirements of this specification. It shall be the responsibility of the manufacturer to perform or to have performed all the tests specified.

2.4.5.2 Copies of previous Type Test Certificates and Type Test Reports by the relevant

International or National Testing/Standards Authority of the country of manufacture (or ISO/IEC 17025 accredited laboratory) shall be submitted with the offer for evaluation (all in English Language). A copy of accreditation certificate for the laboratory shall also be submitted. Any translations of certificates and test reports into English language shall be signed and stamped by the Testing Authority.



Copies of type test reports (as per IEC 60099-4) to be submitted for tender evaluation shall include the following;

2.4.5.3 Insulation withstand tests on the arrester housing; 2.4.5.4 Residual voltage tests; 2.4.5.5 Long duration current impulse withstand test; 2.4.5.6 Operating duty tests; 2.4.5.7 Tests of arrester disconnectors.

2.4.5.8 Routine/sample test reports for the surge arresters to be supplied shall be submitted to KPLC for approval before shipment/delivery of the goods. KPLC Engineers (2) shall witness tests at the factory before shipment.

Tests to be witnessed by KPLC Engineers at the factory shall include the following:

2.4.5.9 Measurement of reference voltage; 2.4.5.10 Residual voltage test; 2.4.5.11 Measurement of power frequency voltage on the complete arrester; 2.4.5.12 Lightning impulse residual voltage on the complete arrester; 2.4.5.13 Partial discharge test.

2.4.5.14 On receipt of the surge arresters, KPLC will inspect them and may perform or have

performed any of the relevant tests in order to verify compliance with the specification. The supplier shall replace without charge to KPLC, surge arresters which upon examination, test or use fail to meet any or all of the requirements in the specification.

2.4.6 MARKING, LABELLING, INSTRUCTIONS AND PACKING

2.4.6.1 The following information shall be marked indelibly and legibly on a nameplate

attached permanently to each surge arrester: h) Continuous operating voltage; i) Rated voltage; j) Rated frequency; k) The manufacturer’s name, type and identification of the complete arrester; l) The year of manufacture; m) Serial number; n) Line discharge class and current. All marking shall be by engraving (or superior method).

2.4.6.2 A set of three (3) original installation and technical manuals for the surge arresters shall be submitted with the equipment. Details on the pressure relief and surge counter shall also be submitted.

2.4.6.3 The surge arresters shall be packed in wood crates which are reinforced and held

closed by external steel wire bindings. Each crate shall be internally braced to permit stacking and the steel wire bindings shall be designed to keep the crate firmly closed and permit easy and rapid opening at time of installation.

The crates shall then be stacked on sturdy wood pallet. The assembly shall be held tightly in place with steel bands and protected against moisture by a complete covering of heat-shrinkable polyethylene film.



2.5 SPECIFICATION FOR 66KV LINE POST INSULATORS

2.5.1. SCOPE 2.5.1.1This specification is for line post insulators for use on overhead power distribution lines operating at 66kV 50Hz on either wood or pre-stressed round hollow concrete poles. 2.5.1.2 This specification covers the following insulators: (i) Type 1A: 66kV Line Post Insulators of Porcelain Material for use on wooden poles. (ii) Type 1 B: 66kV Line Post Insulators of Porcelain Material for use on concrete poles. (iii) Type 2A: 66kV Line Post Composite Insulators (Silicon Rubber) for use on wooden poles. (iv) Type 2B: 66kV Line Post Composite Insulators (Silicon Rubber) for use on concrete poles The specification also covers inspection and test of the insulators as well as schedule of Guaranteed Technical Particulars to be filled, signed by the manufacturer and submitted for tender evaluation. The specification stipulates the minimum requirements for 66kV line post insulators acceptable for use in the company and it shall be the responsibility of the Manufacturer to ensure adequacy of the design, good workmanship and good engineering practice in the manufacture of the insulators for KPLC. The specification does not purport to include all the necessary provisions of a contract. 2.5.2. REFERENCES The following standards contain provisions which, through reference in this text constitute provisions of this specification. Unless otherwise stated, the latest editions (including amendments) shall apply. IEC 720: Characteristics of line post insulators. IEC 168: Tests on indoor and outdoor post insulators of ceramic material or glass for systems

with nominal voltages greater than 1000V. IEC 815: Guide for the selection of insulators in respect of polluted conditions. IEC 1109: Composite insulators for a.c. overhead lines with a nominal voltage greater than

1000V - Definitions, test methods and acceptance criteria. ISO 1461: Hot dip galvanized coatings on fabricated iron and steel articles. Specifications and

test methods. 2.5.3. TERMS AND DEFINITIONS For the purpose of this specification, definitions given in the reference standards shall apply. 2.5.4. REQUIREMENTS 2.5.4.1. SERVICE CONDITIONS As stated in clause 1.5 2.5.4.2. MATERIALS AND CONSTRUCTION 2.5.4.2.1 The insulating material shall be porcelain or silicon rubber.



2.5.4.2.1.1 Where porcelain is used, it shall be sound, free from defects, thoroughly vitrified, smoothly glazed and of uniform brown colour.

2.5.4.2.1.2 Composite insulator shall be made of composite materials of high resistance to

moisture, ultraviolet radiation, high temperatures and tropical sunshine conditions. The core shall be made of resin-impregnated glass fibres free from defects. The housing of the insulator shall be manufactured from high quality silicone rubber. The final colour of the isulator housing shall be BROWN.

2.5.4.2.2 The post insulator shall be free from stresses due to expansion and contraction in any

part which may lead to deterioration. No chemical reaction between materials due to contact shall be allowed (e.g. between cement and metal fittings).

2.5.4.2.3 The under surface and grooves of sheds or skirts shall be easy cleaning. Sheds shall be

substantially symmetrical in shape without appreciable warping. 2.5.4.2.4 The line post insulator shall be of clamp-top type suitable for both vertical and

horizontal mounting as per IEC 720, and as follows: (a) Horizontal mounting

i) Wooden poles: the insulator shall be complete with an integral curved base suitable for direct bolting (by two bolts) onto a wooden pole. The bolt size shall be M20.

ii) Concrete poles: The insulator shall be complete with galvanized metal brackets/fittings for attachment to prestressed round concrete pole at an angle of 5° from the horizontal. The brackets and fittings shall withstand the failing load of the insulator.

iii) Galvanizing shall be in accordance with IS01461.

(b) Vertical mounting i) Wooden poles: the insulator shall be complete with a longitudinal bracket and

accessories suitable for direct bolting (by two bolts) onto a wooden pole. The bolt size shall be M16.

ii) Concrete poles: The insulator shall be complete with galvanized metal brackets/fittings for attachment to prestressed round concrete pole. The brackets and fittings shall withstand the failing load of the insulator.

iii) Galvanizing shall be in accordance with IS01461.

(c) Each line post insulator shall be complete with conductor connector (clamp-top type) suitable for aluminium conductors of sizes 150-300mm2. Detailed drawings showing required mounting arrangements and accessories shall be submitted with the Tender for evaluation. 2.5.4.3. RATINGS 2.5.4.3.1 The mechanical and electrical ratings of the insulators shall be as follows: Minimum failing load 12.5kN Minimum creepage distance 1800 mm (25 mm/kV) Minimum Dry Arcing distance 686mm Minimum wet power frequency withstand voltage 170kV Minimum lightning impulse withstand voltage 350kV



2.5.4.4 QUALITY MANAGEMENT SYSTEM 2.5.4.4.1 The supplier shall submit a quality assurance plan (QAP) that will be used to ensure

that the insulator design, material, manufacture, workmanship, tests, service capability, maintenance and documentation, will fulfill the requirements stated in the contract documents, standards, specifications and regulations. The QAP shall be based on and include relevant parts to fulfill the requirements of ISO 9001:2008.

2.5.4.4.2 The Manufacturer's Declaration of Conformity to reference standards and copies of quality management certifications including copy of valid and relevant ISO 9001: 2008 certificate shall be submitted with the tender for evaluation.

2.5.4.4.3 Details and supporting documents for the manufacturer's experience and manufacturing capacity of similar insulators shall be submitted with the tender.

2.5.5. TESTS AND INSPECTION 2.5.5.1 Type tests, routine tests, and sample tests shall be done in accordance with the

requirement of IEC 168, IEC 1109 and the requirements of this specification. It shall be the responsibility of the manufacturer to perform or to have performed the tests specified and other tests normally performed at works.

2.5.5.2 Copies of previous Test Reports from the National or International Testing Authority or an ISO/IEC 17025 accredited independent Laboratory shall be submitted with the tender for the purpose of technical evaluation, all in the English Language. Copies of Test Reports to be submitted shall include Design and Type Tests in accordance with IEC 168 and IEC 1109.

2.5.5.3 Routine and Sample Test Reports for the insulators to be supplied shall be submitted to KPLC for approval before shipment/delivery of the goods. The Test Reports shall be from an ISOIIEC 17025 accredited Laboratory.

2.5.5.4 On receipt of the insulators, KPLC may perform routine and sample tests in order to verify compliance with specification. The supplier shall replace without charge to KPLC, any insulators which upon examination, test or use fail to meet any of the requirements in this specification.

2.5.6. PACKING. MARKING AND INSTRUCTIONS 2.5.6.1 The following information shall be marked indelibly and legibly on the insulator:

i) Manufacturers Name or Trademark ii) Type Designation and Batch Number iii) Year of manufacture iv) Failing Load (cantilever) v) The letters 'KPLC'

2.5.6.2 Instructions for storage, handling and installation shall be included in each package, all in the English Language.

2.5.6.3 The insulators shall be packed in wood crates which are reinforced and held closed by

external steel wire bindings. Each crate shall be internally braced to permit stacking and the steel wire bindings shall be designed to keep the crate firmly closed and permit easy and rapid opening at time of installation.



The crates shall then be stacked on sturdy wood pallet. The assembly shall be held tightly in place with steel bands and protected against moisture by a complete covering of heat-shrinkable polyethylene film .

2.6 SPECIFICATION FOR 33 AND 11kV COMPOSITE INSULATORS 2.6.1 SCOPE

2.6.1.1 This specification is for composite insulators for use on overhead lines for tension and suspension purposes. 2.6.1.2 This specification covers the following composite insulators.

(i) 11kV composite insulator (ii) 33kV composite insulator

2.6.2 REFERENCES

The following documents were referred to during the preparation of this specification.

In case of conflict, the provision of this specification shall take precedence. Unless otherwise specified, the latest revision, edition and amendments shall apply.

IEC 120: Dimensions of ball and socket couplings of string insulator units. IEC 815 Guide for the selection of insulators in respect of polluted conditions. IEC 1109: Composite insulators for ac overhead lines with a nominal voltage

greater than 1000V.

2.6.3 TERMS AND DEFINITIONS For the purpose of this specification, the definitions in the reference standards shall apply. 2.6.4 SERVICE CONDITIONS

As stated in clause 1.5

2.6.5 MATERIAL AND CONSTRUCTION

2.6.5.1 The insulator shall have a core made of resin-impregnated glass

fibre free from defects. 2.6.5.2 The housing of the insulator shall be manufactured from high

quality silicone. 2.6.5.3 The insulator shall be free from stresses due to expansion and

contraction in any part, which may lead to deterioration. 2.6.5.4 The insulator shall be of high resistance to moisture and

ultraviolet radiation. 2.6.5.5 The insulator shall be fitted with ball and socket coupling in

accordance to IEC 120. 2.6.5.6 The ball pin shall be of medium carbon steel.



2.6.5.7 The ball pin diameter shall be 16mm and shall be supplied separately with a corresponding “R” form retaining clip.

2.6.5.8 The security clip shall be of stainless steel or an approved copper alloy.

2.6.6 CHARACTERISTICS

The mechanical and electrical characteristics of the insulators shall be as follows:-

CHARACTERISTICS 11kV INSULATOR 33kVINSULATOR Dry Arc Distance 225 mm 385 mm Minimum Creapage Distance

300 mm 900 mm

Minimum Power Frequency Withstand Voltage (wet)

30 kV 70 kV

Minimum Lighting Impulse Withstand Voltage

95 kV 200 kV

Minimum Failing Load 70 kN 70 kN 2.7 SPECIFICATIONS FOR 66KV COMPOSITE INSULATORS

This specification has been prepared by the Research and Development Department of The Kenya Power and Lighting Company Limited (KPLC) and it lays down requirements for 66kV Suspension/Tension Type Composite Insulators. It is intended for use by KPLC in purchasing the insulators. The manufacturer shall submit information which confirms satisfactory service experience with products which fall within the scope of this specification.

2.7.1 SCOPE

This specification is for composite insulators for use on overhead lines for tension and suspension purposes. The specification covers 66kV Suspension/Tension composite line insulators. The specification stipulates the minimum requirements for 66kV Suspension/Tension composite line insulators acceptable for use in the company and it shall be the responsibility of the manufacturer to ensure adequacy of the design, good workmanship and good engineering practice in the manufacture of the insulators for KPLC. The specification also covers inspection and test of the insulators as well as schedule of Guaranteed Technical Particulars to be filled, signed by the manufacturer and submitted for tender evaluation The specification does not purport to include all the necessary provisions of a contract.

2.7.2 REFERENCES



The following standards contain provisions which, through reference in the text constitute provisions of this specification. Unless otherwise stated, the latest editions (including amendments) apply. IEC 120: Dimensions of ball and socket couplings of string insulator units.

IEC 815: Guide for the selection of insulators in respect of polluted conditions. ISO 1461: Metallic Coatings – Hot dip galvanized coatings on fabricated ferrous products

– Requirements. ISO 1460: Metallic Coatings – Hot dip galvanized coatings on fabricated ferrous metals –

Determination of mass per unit area – Gravimetric method. IEC 1109: Composite insulators for a.c. overhead lines with a nominal voltage greater

than 1000V – Definitions, test methods and acceptance criteria. 2.7.2.1 TERMS AND DEFINITIONS

For the purpose of this specification the terms and definitions given in the reference standards shall apply.

2.7.2.2 REQUIREMENTS 2.7.3 SERVICE CONDITIONS

The insulators shall be suitable for continuous operation outdoors in tropical areas at altitudes of up to 2200m above sea level, humidity of up to 90%, average ambient temperature of +30ºC with a minimum of -1ºC and a maximum of +40ºC, heavy saline conditions along the coast and tropical sunshine conditions. The level of galvanizing for all ferrous parts and materials used shall be suitable for these conditions.

2.7.4 MATERIALS AND CONSTRUCTION 2.7.4.1 The insulators shall be manufactured to IEC 61109, other applicable /latest IEC standards and the requirements of this specification. 2.7.4.2 The insulator shall have a core made of resin-impregnated glass fibres free from defects. The

housing of the insulator shall be manufactured from high quality silicone rubber. 2.7.4.3 The insulator shall be of high resistance to moisture and ultraviolet radiation and shall

withstand high tropical sunshine conditions. 2.7.4.4 The final colour of the insulator housing shall be GREY. 2.7.4.5 The insulator shall be fitted with ball and socket coupling in accordance with IEC 120.

The ball pin and socket shall be of medium carbon steel with hot dip galvanized finish. Galvanizing shall be to ISO 1461.



The ball pin diameter shall be 16mm and shall be supplied complete with a corresponding “W” form retaining clip. The security clip shall be of stainless steel.

2.7.5 CHARACTERISTICS

The mechanical and electrical characteristics of the insulators shall be as

follows:-

Description Requirement System Highest Voltage 72.5kV, 50Hz Minimum Creepage Distance 1800mm Minimum Power Frequency Withstand Voltage (wet) [altitude correction factor of 1.16 applied on 140kV]

160kV, rms

Minimum Lighting Impulse Withstand Voltage (dry) [altitude correction factor of 1.16 applied on 325kV]

380kV (1.2/50µs positive)

Minimum Arc Distance (between metal fittings) 720mm Minimum Failing Load 70kN

2.7.5.2 TESTS AND INSPECTION 2.7.5.2.1 Design tests, type tests, sampling tests and routine tests shall be done in accordance with

the requirement of IEC 61109, IEC 60383, ISO 1460 and the requirements of this specification. It shall be the responsibility of the manufacturer to perform or to have performed all the tests specified.

2.7.5.2.2 Certified true copies of previous design and type test reports by the relevant

Independent/International or National Testing/Standards Authority of the country of manufacture (or ISO/IEC 17025/ILAC accredited laboratory) shall be submitted with the offer for evaluation (all in English Language). A copy of accreditation certificate for the laboratory shall also be submitted.

Copies of test reports for the following Design and Type Tests shall be submitted for tender evaluation:

2.7.5.2.3 Tests on interfaces and connections of metal fittings; 2.7.5.2.4 Assembled core load-time test; 2.7.5.2.5 Test of housing: tracking and erosion test. The test reports MUST include resistance to

ageing tests by KEMA or equivalent Testing Authority (under climate chambers to mimic the conditions – sunshine, salinity, temperature, humidity, spray and so on – typical of tropical climate and those stated in clause 4.1 in addition to the highest system voltage);

2.7.5.2.6 Tests for the core material; 2.7.5.2.7 Flammability test; 2.7.5.2.8 Dry lightning impulse withstand voltage test; 2.7.5.2.9 Wet power frequency test; 2.7.5.2.10 Mechanical load-time test and test of the tightness of the interface between end fittings

and insulator housing.



2.7.5.2.11 Routine and sample test reports for the insulators to be supplied shall be submitted to KPLC for approval before shipment/delivery of the goods. KPLC Engineers (2) will witness acceptance tests at the factory before shipment.

Acceptance tests shall include the following tests as per IEC 1109 and applicable latest IEC standards:

2.7.5.2.12 Verification of dimensions; 2.7.5.2.13 Verification of the locking system; 2.7.5.2.14 Verification of tightness of the interface between end fittings and insulator housing; 2.7.5.2.15 Verification of the specified mechanical load; 2.7.5.2.16 Galvanizing test (by Gravimetric method).

2.7.5.2.17 On receipt of the insulators, KPLC will inspect them for acceptance at stores and may

perform or have tests performed in order to verify compliance of the insulators with this specification.

The supplier shall replace without charge to KPLC, any insulators which upon

examination, test or use fail to meet any or all of the requirements in this specification. 2.7.6 MARKING AND LABELLING 2.7.6.1 The following information shall be marked indelibly and legibly and in a permanent manner

on each insulator.

i) Manufacturer’s Name or Trademark; ii) Manufacturer’s Type Designation; iii) Specified Electrical Characteristics; iv) Specified Mechanical Load.

2.7.6.2 All marking shall be by embossing and any on metal fittings shall be before galvanizing. The

marking shall not affect the performance of the insulator.

2.7.6.3 A set of Three (3) installation and technical manuals for the insulators shall be submitted during delivery.

2.8 SPECIFICATIONS FOR STAY, STAY INSULATORS AND STAY BLOCKS 2.8.1 SCOPE

a) This specification is for stay insulators for use on overhead power distribution lines

operating at a nominal voltage of up to 33 kV.

ii) This specification covers the following standard insulators • Stay insulator for Low Voltage lines. • Stay insulator for 11kV Voltage lines. • Stay insulator for 33kV Voltage lines.

2.8.2 REFERENCES



The following documents were referred to during the preparation of this specification, and may be further consulted. In case of conflict, however, the provision of this specification shall take precedence.

Unless otherwise specified, the latest revision, edition and amendments shall apply.

• IEC 720: Characteristics of line post insulators.

• IEC 168: Tests on indoor and outdoor post insulators of ceramic material or glass for

systems with nominal voltages greater than 1000V.

• IEC 815: Guide for the selection of insulators in respect of polluted conditions.

• BS 137 Insulators of ceramic material or glass for overhead lines with a nominal voltage greater than 1000V.

o Part 1 Methods of test o Part 2 Requirements

(e) ESI.43-91 - Stay strands and stay fittings for overhead lines.


For the purpose of this specification, the definitions in the reference standards shall apply.

2.8.4 SERVICE CONDITIONS As stated in clause 1.5

2.8.5 MATERIAL AND CONSTRUCTION 2.8.5.1 The insulating material shall be porcelain or composite with the approval of the Employer. 2.8.5.2 The porcelain shall be sound, free from flaws and blemishes, thoroughly vitrified, smoothly glazed and of uniform brown colour when finished. 2.8.5.3 The insulator shall be free from stresses due to expansion and contraction in any part which may lead to deterioration. 2.8.5.4 The holes in the insulator shall be smoothly radiused with as large a radius as practicable to present an even bearing surface to the stay strand loop.

2.8.6 PARTICULAR REQUIREMENTS 2.8.6.1 Particular requirements for Low Voltage stay Insulators

The insulator shall be sling type strain insulator suitable for stay wire size 7/4.00m. • The minimum failing load shall be 48 kN • The minimum dry lightning impulse withstand voltage 20 kV



2.8.6.2. Particular requirements for 11kV stay Insulators

The insulator shall be string type strain insulator suitable for stay wire size 19/3.55mm. • The minimum failing load shall be 110kN. • Minimum wet power frequency withstand voltage 20 kV (r.m.s.) • Minimum dry lightning impulse withstand voltage 60 kV (peak)

2.8.6.3. Particular requirements for 33kV stay Insulators

The insulator shall be string type strain insulator suitable for stay wire size 19/3.55mm.

• The minimum failing load shall be 110kN. • Minimum wet power frequency withstand voltage 48 kV (r.m.s.) • Minimum dry lightning impulse withstand voltage 100 kV (peak)

2.8.7 STAY

2.8.7.1 SCOPE

This specification covers the design, manufacture testing and supply of galvanized stranded steel wire for use as stays and for similar purposes on overhead power distribution lines. This specification covers the following steel wire sizes.

• 7/4.00/700 Stranded Stay Wire




2.8.7.2 REFERENCES

The equipment shall comply with the latest edition and amendments of the Standards listed herein.

• BS 183:Specification for general purpose galvanized steel wire strand.

• BS 443:Specification for testing zinc coatings on steel wire and for quality

requirements.

• ANS C7.46:Standard specification for zinc-coated steel wire strand.

• ES1 43-91:Stay strands and stay fittings for overhead lines.

2.8.7.3 MATERIAL (a) The base metal shall be steel made by the open-hearth, basic-oxygen or electric-

furnace process and of such quality and purity that, when drawn to the size of wire specified and coated with zinc, the finished strand and the individual wires shall be of



uniform quality and have the properties and characteristics as specified in this specification.

(b) The galvanized steel wires used in the construction of the stay wire shall comply with

the requirement of BS 443.

2.8.7.4 CONSTRUCTION The stay wire shall be manufactured as per the requirement of BS 183. The outer wires of all strands shall have a right-hand lay (Z). All wires shall be stranded with uniform tension. Stranding shall be sufficiently close to ensure no appreciable reduction in diameter when stressed to 10% of the specified wire strength. The wires shall be concentrically twisted with a uniform pitch of not less than 10 nor more than 18 times the specified nominal diameter of the strand. Joints made in individual wires shall be accepted provided there is not more than one joint in any 45m section of the completed strand. Joints made during stranding shall be protected against corrosion.

2.8.7.5 STANDARD SIZES

The standard sizes for the stay wires shall be as follows:-

STANDARD NEAREST EXISTING SIZE SIZE GRA

DE MINIMUM BREAKING LOAD

KPLC CODE

SIZE QUALITY

MINIMUM BREAKING LOAD

7/4.00 700 61.6 kN 89737 7/8 Stay Wire

45 ton/in2 6430 kg

19/3.55 700 131.6 kN 89739 19/10 Stay Wire

45 ton/in2 11180 kg

7/2.00 700 15.4 kN 89743 7/14 Stay Wire

45 ton/in2 1610 kg

4/4.00 700 35.2 kN 89748 4/8 Stay Wire

45 ton/in2 3680 kg

2.8.8 TESTS

The diameter of the wires shall be tested in accordance with the requirement of BS 183.

Tensile test, Elongation test and wrapping test shall be done in accordance with the requirement of BS 183.



Uniformity, adherence and mass of coating shall be tested as per BS 443.

2.8.9 PACKING

The complete stay wire shall be rolled in a coil and packed in a manner as to protect it from any damage in transportation and repeated handling. The completed coil shall be tagged. The following description shall be marked on the tag.

• Type of stay wire. • Length. • Manufacturer’s name. • Year of manufacture.

2.8.10 STAY RODS AND TURNBUCKLES

2.8.11.1 SCOPE

This specification covers the design, manufacture testing and supply of tubular stay rods and turnbuckles for use on stays and for similar purposes on overhead power distribution lines.

This specification covers the following sizes:

(a) Tubular Stay Rods:

• 6ft x 5/8” • 8ft x ¾” • 9ft x 1”

(b) Turnbuckle double eye bolt:

• 10” x 5/8” • 12” x ¾” • 10” x ⅞”

2.8.11.2 REFERENCES

The equipment shall comply with the latest edition and amendments of the Standards listed herein.

• BS 464: Specification for thimble for wire ropes.

• BS 729: Specification for hot dip galvanized coating on iron and steel articles.

• BS 1387: Specification for screwed and socketed steel tubes and tubular and for

plain and steel tubes suitable for welding or screwing to BS 21 pipe threads.

• BS 3643: ISO metric screw threads.

• BS 4360: Specification for weldable structural steels.

2.8.11.3 MATERIAL



(a) Tubular Stay Rods

The tubular turnbuckle (the tube portion of the adjustable rod) shall be manufactured from heavy gauge steel tube as specified in BS 1387, table 3.

The threads shall be to BS 3643, coarse pitch, tolerance class 7H/8g (free fit).

The screw-in stay anchor and the adjustable head shall be manufactured from Grade 43A steel as specified in BS 4360.

The thimble shall be manufactured from standard crescent shaped steel bar as used for thimbles to BS 464.

(b) Turnbuckle double eye bolt

The turnbuckle shall be manufactured from Grade 43A steel as specified in BS 4360. The Threads shall be to BS 3643, course pitch tolerance class 7H/8g (free fit)

2.8.11.4 CONSTRUCTION

(a) Tubular Stay Rods

The tubular turnbuckle shall have hexagon head, solid forged on one end of tube.

The stay anchor and the adjustable head shall have hexagon lock nuts of the same size as the hexagon head of the tubular turnbuckle.

The lower end of the stay anchor shall be forged square to fit square plate. The square plate shall be 100mm by 100mm by 6mm in dimension, for securing the rod to a concrete stay block. The stay adjustable head shall have a forged eye with a thimble suitable for the specified stay wire sizes. The stay rod assembly shall be galvanized to BS 729. The complete stay rod assembly shall have the minimum failing load as stated in clause 5. (b) Turnbuckle double eye bolt

The turnbuckle shall have a forged eye bolt at each end and shall be supplied complete with hexagon lock nuts. The turnbuckle shall be double screw threaded in opposite directions to achieve simultaneous adjustment/tightening.

The complete turnbuckle assembly shall be galvanized to BS 729 and have the minimum failing load as stated in clause 5.

2.8.11.5 STANDARD SIZES (a) The standard sizes for the Tubular Stay Rods shall be as follows:-



KPLC CODE SIZE MINIMUM

FAILING LOAD SIZE OF STAY WIRE

186525 6ft x 5/8”

36.8 kN 4/8 stay wire

186531

8ft. x ¾”


186533 9ft. x 1”


(b) The standard sizes for the Turnbuckles (double eye bolt) shall be as follows:-

KPLC CODE SIZE MINIMUM FAILING LOAD

SIZE OF STAY WIRE

189306 10” x 5/8”


189307

12” x ¾”


189308

10” x 7/8”


2.8.11.6 TESTS

The complete Tubular Stay Rod and Turnbuckle shall be tested to determine the minimum failing load.

Uniformity, adherence and mass of coating of the galvanizing shall be done in accordance with BS 729. 2.8.12 STAY BLOCK A reinforced concrete stay block buried to the depth of at least 1.4m shall be used as the stay anchor.

2.9 SPECIFICATION FOR STAY INSULATORS UPTO 66KV 2.9.1 SCOPE

2.9.1.1 This specification is for stay insulators for use on overhead power distribution lines operating at nominal voltages of up to 66 kV 50Hz. The specification covers the following stay insulators

• Stay Insulator for Low Voltage Lines • Stay Insulator for 11kV Lines • Stay Insulator for 33kV Lines • Stay Insulator for 66 kV Lines

Particular requirements for each insulator type as may be relevant for a specific requisition are given in Clause 4.3.



2.9.2 REFERENCES

The following documents were referred to during the preparation of this specification. In case of conflict, the provisions of this specification shall take precedence.

• IEC 60383: Tests on insulators of ceramic material or glass for overhead lines with a nominal voltage greater than 1000V.

• IEC 60060-1: High-voltage test techniques. Part 1: General definitions and test

requirements.

• IEC 61109: Composite insulators for a.c. overhead lines with a nominal voltage greater than 1000V – Definitions, test methods and acceptance criteria.

• BS 183: Specification for general purpose galvanized steel wire strand.

• BS 729: Specification for hot dip galvanized coatings on iron & steel articles


For the purpose of this specification, definitions given in the reference standards and the following shall apply:

Stay insulator – An insulator intended to be inserted in a stay wire to electrically isolate the lower part of the stay from the pole top and so designed as to provide a high lightning impulse withstand voltage. The Stay Insulator is also referred to as Guy Strain Insulator.

2.9.4 REQUIREMENTS 2.9.4.1 Service Conditions

As stated in clause 1.5 2.9.4.2 Design, Materials and Construction

The insulators shall be designed and manufactured for the purpose of providing a high impulse level withstand in the stay assembly whilst accommodating the maximum tensile forces that may be imposed.

The insulators shall comply with the electrical and mechanical requirements of this specification and shall retain these properties during the normal life of thirty years in service conditions given in 4.1 above. The dielectric component of the insulator shall comprise a fibreglass rod with continuous, unidirectional fibres running axially from end-to-end. The rod shall be coated with a uv-resistant epoxy or polyurethane material. Other composite materials to IEC 61109 shall also be considered. The end caps shall be the thimble type, produced from forged steel and hot dip galvanized (heavy duty) in accordance with BS 729. The thimble groove shall be



smooth and have a minimum cross-sectional radius suitable for specified stay wire size.

2.9.4.3 Particular Requirements

2.9.4.3.1 Particular Requirements for Stay Insulators for Low Voltage Lines The insulator shall be strain type suitable for stay wire size 4/4.00mm Grade 700 (4/8 SWG), stay wire to BS 183.

• The minimum failing load shall be: 36 kN • The minimum power frequency withstand voltage, wet: 15kV

2.9.4.3.2 Particular requirements for Stay Insulators for 11kV Lines

The insulator shall be strain type suitable for stay wire size 7/4.00mm Grade 700 (7/8 SWG), stay wire to BS 183.

• The minimum failing load shall be: 65 kN • The minimum power frequency withstand voltage, wet: 38 kV • The minimum impulse withstand voltage, positive: 95kV







2.9.5 MARKING The following information shall be clearly and indelibly marked on each insulator:

• Name or trade mark of the manufacturer • Year of manufacture • The words “PROPERTY OF KPLC” • Electrical and Mechanical Characteristics

The marking may be printed or impressed provided such impressions do not impair the performance of the insulator.



2.9.6 TESTS AND INSPECTION Refer to clause 1.16

a) Type tests, routine tests and sample tests shall be done following procedures specified in IEC 60383 and IEC 60060-1 and the requirements of this specification. It shall be the responsibility of the manufacturer to perform or to have performed the tests specified.

b) Copies of previous Type Test Reports certified by the National Testing/ Standards

Authority of the country of manufacture or its accredited testing laboratory shall be submitted with the tender for the purpose of technical evaluation, all in English. Type test reports to be submitted shall include dry lightning impulse withstand voltage test, wet power-frequency withstand voltage test and test for mechanical strength.

c) A sample of each type of stay insulator offered shall be submitted with the bid documents

for evaluation.

d) Upon completion of manufacturing process, the stay insulators shall be subject to inspection by two KPLC Engineers at place of manufacture and sample tests carried out in their presence. The sample tests shall include verification of dimensions, test for mechanical strength, electrical characteristics and galvanizing test, all in accordance with IEC 60383.

e) Routine and Sample Test Reports shall be completed and submitted to KPLC for approval

before shipment of the materials.

f) On receipt of the goods KPLC may perform any of the tests specified in order to verify compliance with this specification. The supplier shall replace without charge to KPLC insulators which upon examination, test or use fail to meet any of the requirements in the specification.

2.9.7 TECHNICAL DOCUMENTATION

Technical details and drawings for the insulators to be supplied shall be submitted to KPLC for approval before manufacture commences.

2.10 SPECIFICATION FOR 33 KV EXPULSION FUSE CUT-OUT 2.10.1 SCOPE

This specification is for 33 kV Expulsion Fuse cut-Out for use in protection and isolation of substation apparatus and sectionalising purposes.


As stated in clause 1.5

2.10.3 CONSTRUCTION



2.10.3.1 The fuse mount shall incorporate porcelain insulators to suit voltage requirements and removable drop out expulsion fuse link carrier, suitable for fuse links of the button head single tail type.

o The fuse cut-out shall be mounted on a hot dipped galvanised steel bracket suitable

for vertical mounting.

o Galvanising shall be as per the requirement of BS 729.

2.10.3.2 The fuse carrier shall be of the vertical opening, single pole operation and suitable for manual removal from and insertion into the fuse mount from ground level with the aid of an insulated operating stick.

2.10.3.3 The fuse mount shall be arranged such that each unit is mounted on an angle bracket or channel base mounting.

2.10.3.4 The fuse carrier shall be spring loaded at the lower end to ensure an even tension on the fuse link and adequate contact pressure to assist in expelling the link tail from the carrier when fuse blows.

2.10.3.5 The fuse carrier shall be designed such that it is removable from the fuse mount and when removed, shall provide adequate electrical isolation between the contact points.

2.10.3.6 All current carrying parts shall be of electrolytic high conductivity material. 2.10.4 RATING

The rating of the fuse cut-out assembly shall be as follows:- Rated voltage 36 kV Rated lightning impulse withstand voltage 170 kV Rated power frequency withstand voltage (wet) 70 kV Rated frequency 50 Hz Rated short time withstand current for 3 seconds 25 kA Minimum creepage distance 1000 mm

2.25.5 TEST The fuse mount shall be inspected and tested in accordance with the requirement of this specification. 2.11 SPECIFICATION FOR 33 KV EXPULSION FUSE HOLDER 2.11.1 SCOPE

This specification is for 33 kV drop out expulsion fuse holder for use on line disconnection, isolation of substation apparatus and sectionalising purposes.





2.11.3.1 The fuse holder (carrier) shall be of the vertical opening, single pole operation and suitable for manual removal from and in section into the fuse mount from ground level with the aid of insulated operating stick.

2.11.3.2 The fuse holder shall be suitable for use on drop out expulsion fuse isolator. The fuse holder shall be designed and manufactured to accommodate standard expulsion fuse link of the button head single tail type.

2.11.3.3 The fuse holder shall be spring loaded at the lower end to ensure an even tension on the fuse link and adequate contact pressure to assist in expelling the link tail from the holder when fuse blows.

2.11.3.4 The fuse holder shall be designed such that it is removable from the fuse mount and when removed, shall provide adequate electrical isolation between the contact points.

2.11.3.5 All current carrying parts shall be of electrolytic high conductivity material with the contacts hard drawn and silver plated.

2.11.4 RATING

The rating of the fuse holder shall be as follows:- Rated voltage 36 kV Rated lightening impulse withstand voltage 170 kV Rated power frequency withstand voltage (wet) 95 kV Rated frequency 50 Hz Rated short time withstand current for 3 seconds 12.5 kA Minimum creepage distance 1000 mm Length 482.6 mm (19”)

2.11.5 TESTS

The fuse holder shall be inspected and tested in accordance with the requirement of this specification.



Part 3: Technical Schedules



3. GUARANTEED TECHNICAL PARTICULARS. 3.1 PREAMBLE 3.1.1 The Guaranteed Technical Particulars Schedules shall be filled in and completed by the Bidder, and submitted with the Bid. 3.1.2 All documentation necessary to evaluate whether the equipment offered is in accordance with this Specification shall be submitted with the Bid. 3.1.3 All data entered in the Schedules of Technical Guarantees are guaranteed values by the Bidder and cannot be departed from except with a written consent of the Client’s Project Manager.

ANNEX A: Guaranteed Technical Particulars these must be filled and signed by the

Manufacturer for all clauses and submitted together with copies of the manufacturer’s catalogues, brochures, drawings, copies of type test reports, customers sales records, customer reference letters and details of production capacity and manufacturing experience in the manufacture of each item bid for tender evaluation, all in English language

Note: This schedule does not in any way substitute for detailed information required elsewhere in the specification.

3.1 300mmsq ALL ALUMINIUM ALLOY CONDUCTOR – NOT REQUIRED



3.2 66KV DISCONNECTORS (AIR BREAK SWITCHES) NNo

REQUIREMENTS GUARANTEED PARTICULARS

COMMENTS

11 Name of the manufacturer and country of manufacture

22 Applicable standards 33 Service (indoor/outdoor), altitude, temperature

range, humidity, environment (pollution severity level), wind speed etc

44 Type Model/Type Reference Number

Breaking medium 55 Steelwork & components to be supplied

(including components and mounting stalk for mounting on wooden or concrete poles at a height of 12m above ground level)

66 Operating mechanism 77 Contacts Materials

Thickness of silver coating Contact resistance Current Density

Moving blade

Terminal pad Contacts Terminal connector

Spare contacts (five male & five female)

88 Rating Nominal System Voltage and frequency

Highest System Voltage of equipment

Rated continuous current

Rated short circuit withstand current & time

Rated short circuit making current

Breaking capacity of capacitive current

Rated inductive current switching capacity

Max temperature rise under rated voltage and current

Breaking capacity at rated voltage

Lightning impulse withstand voltage, 1.2/50µs, dry, +ve

With contacts closed Across open contacts

One minute power frequency withstand voltage, 50Hz, 60s

With contacts closed

Across open contacts

Creepage distance of insulator



Minimum clearance between phases (phase centres)

Minimum clearance to earth Mechanical endurance (number of close-open cycles without using spare parts)

99 Padlocking facility in both open and closed position

110

Degree of protection

111

Any special assembly tools

112

Corona prevention

113

Manufacturer’s Guarantee and Warranty

114

List catalogues, brochures, technical data, drawings submitted to support the offer.

115

List customer sales records submitted to support the offer.

116

List Type Test Certificates and Type Test Reports submitted with tender (indicate test report numbers, date, Testing Institution and contact addresses)

• Dielectric tests (Lightning Impulse and Power Frequency Withstand Tests),

• Short time withstand and peak withstand current tests,

• Temperature rise test, • Measurement of the resistance of

circuits, • Verification of the protection, • Tightness tests, • Electromagnetic compatibility tests, • Operation and mechanical

endurance tests, • Operation at the temperature limits.

117.

List Acceptance Tests to be witnessed by KPLC Engineers at the factory

118.

List test reports (for disconnector and components) to be submitted to KPLC for approval before shipment

119.

Copy of ISO 9001:2008 Certificate submitted (indicate relevance and validity)

220.

Quality Assurance Plan

221.

Manufacturer’s Declaration of Conformity to Standards (including IEC 62271-102)

22 Statement of compliance to tender specifications



2. 223.

Guaranteed reliability and maintenance indicators:

a) reliability (MTBF) b) availability (A) c) maintainability (MTTR) d) service life e) warranty period of actuating under

normal service conditions without maintenance

224.

Deviations from tender specifications and supporting data, test reports, technical documents etc.

225.

Inspection of the disconnector and components at KPLC stores/site.

226.

List and details of auxiliaries, fittings, components and accessories included in scope of supply.

……………………………………………………………………………………………. Manufacturer’s Name, Signature, Stamp and Date



3.3 33KV DISCONNECTORS (AIR BREAK SWITCHES)

N REQUIREMENTS GUARANTEED PARTICULARS

COMMENTS

11. Name of the manufacturer and country of manufacture

22. Applicable standards 33. Service (indoor/outdoor), altitude, temperature

range, humidity, environment (pollution severity level), wind speed etc

44. Type Model/Type Reference Number Breaking medium

55. Steelwork & components to be supplied (including components and mounting stalks for mounting on 12m wooden or concrete poles

66. Operating mechanism 77. Contacts Materials

Thickness of silver coating Contact resistance Current Density

Moving blade Terminal pad Contacts Terminal connector

Spare contacts (five male & five female)

88. Rating Nominal System Voltage and frequency

Highest System Voltage of equipment

Rated continuous current

Rated short circuit withstand current & time

Rated short circuit making current

Breaking capacity of capacitive current

Rated inductive current switching capacity

Max temperature rise under rated voltage and current

Breaking capacity at rated voltage

Lightning impulse withstand voltage, 1.2/50µs, dry, +ve

With contacts closed Across open contacts

One minute power frequency withstand voltage, 50Hz, 60s

With contacts closed

Across open contacts

Creepage distance of insulator Minimum clearance between phases (phase



centres)



Minimum clearance to earth Mechanical endurance (number of close-open cycles without using spare parts)

99. Padlocking facility in both open and closed position

110. Degree of protection 111. Any special assembly tools 112. Corona prevention 113. Manufacturer’s Guarantee and Warranty 114. List catalogues, brochures, technical data,

drawings submitted to support the offer.

115. List customer sales records submitted to support the offer.

116. List Type Test Certificates and Type Test Reports submitted with tender (indicate test report numbers, date, Testing Institution and contact addresses)

• Dielectric tests (Lightning Impulse and Power Frequency Withstand Tests),

• Short time withstand and peak withstand current tests,

• Temperature rise test, • Measurement of the resistance of

circuits, • Tightness tests, • Electromagnetic compatibility tests, • Operation and mechanical endurance

tests, • Operation at the temperature limits.

117. List Acceptance Tests to be witnessed by KPLC Engineers at the factory

118. List test reports (for disconnector and components) to be submitted to KPLC for approval before shipment

119. Copy of ISO 9001:2008 Certificate submitted (indicate relevance and validity)

220. Quality Assurance Plan 221. Manufacturer’s Declaration of Conformity to

Standards (including IEC 62271-102)

222. Statement of compliance to tender specifications

223. Guaranteed reliability and maintenance indicators:

f) reliability (MTBF) g) availability (A) h) maintainability (MTTR) i) service life j) warranty period of actuating under

normal service conditions without



maintenance 224. Deviations from tender specifications and

supporting data, test reports, technical documents etc.

225. Inspection of the disconnector and components at KPLC stores/site.

226. List and details of auxiliaries, fittings, components and accessories included in scope of supply.

227. Details and supporting documents submitted on manufacturer’s experience and manufacturing capacity

……………………………………………………………………………………………. Manufacturer’s Name, Signature, Stamp and Date 3.4 66KV POST INSULATORS Clause number Bidder’s offer (indicate full details of the offered insulator for

each requirement of the specification) 2.5.1 2.5.2 2.5.3 2.5.4.1 2.5.4.2.1 2.5.4.2.2 2.5.4.2.3 2.5.4.2.4 (a) (i)

(a) (ii) (b) (i)

(b) (ii) (c) 2.5.4.3.1 2.5.4.4.1 2.5.4.4.2 2.5.4.4.3 2.5.5.1 2.5.5.2 2.5.5.3 2.5.5.4 2.5.5.4 2.5.6.1 2.5.6.2 2.5.6.3



……………………………………………………………………………………. Manufacturer’s Name, Signature, Stamp and Date

3.5 66KV COMPOSITE INSULATORS

Description Bidder’s offer 1. Service Conditions 2. Applicable Standards 3. Maximum System Voltage (kV) and frequency (Hz) 4. One-minute power frequency withstand voltage, 50Hz, wet (kV)

5. Lighting impulse withstand voltage, 1.2/50µs pos. (kV) 6. Minimum creepage distance (mm) 7. Specified mechanical load, tension (kN) 8. Length of insulator set with fittings (mm) 9. Minimum Arcing Distance (mm) 10. Material of fittings and level of corrosion protection 11. Material of rod 12. Material of housing and sheds 13. Socket, size & standard 14. Ball, size & standard 15. List of copies of Design and Type Test Reports submitted (indicate Test Report Numbers, Testing Authority and contact addresses)

16. List of Acceptance Tests to be witnessed by KPLC Engineers at the factory

17. List of catalogues, brochures, technical data, drawings and customer sales records submitted to support the offer.

18. Inspection for Acceptance to Stores & Guarantee 19. Statement of compliance to specifications

……………………………………………………………………………………………. Manufacturer’s Name, Signature, Stamp and Date 3.6 33KV COMPOSITE INSULATORS

Description Bidder’s offer 1. Manufacturer’s name & address 2. Type Reference Number of insulator offered 3. Service Conditions 4. Applicable Standards 5. Maximum System Voltage (kV) 6. One-minute power frequency withstand voltage, 50Hz, 60s, wet (kV rms)



7. Lighting impulse withstand voltage, 1.2/50µs positive, dry, (kVp)

8. Minimum creepage distance (mm) 9. Specified mechanical load (kN) 10. Length of insulator with fittings (mm) 11. Material of fittings and level of corrosion protection 12. Material of rod 13. Material of housing and sheds 14. Conductor groove, size 15. Suitability for both vertical & horizontal application 16. List of copies of Design and Type Test Reports submitted (indicate Test Report Numbers, Testing Authority and contact addresses)

17. List Acceptance Tests to be witnessed by KPLC Engineers at the factory

18. List of catalogues, brochures, technical data, drawings and customer sales records submitted to support the offer.

19. Marking (indicate parameters and method of marking to be used during manufacture)

20. Copy of ISO 9001:2008 Certificate submitted (indicate validity)

21. Quality Assurance Plan 22. Deviations from tender specifications and supporting data, test reports, technical documents etc.

……………………………………………………………………………………………. Manufacturer’s Name, Signature, Stamp and Date 3.7 66KV SURGE ARRESTORS (DIVERTERS)

Clause Number

Description Bidder’s offer

Manufacturer, Country of origin of surge arresters offered

Type Reference No./Model No. 2.3.4.1 Service Conditions 2.3.4.2.1 Applicable Standard(s) 2.3.4.2.2-4 Type and design 2.3.4.2.5-6 Insulator and sealing 2.3.4.2.7 Pressure relief/ disconnector (and technical

details)

2.3.4.2.8 Surge counter (and technical details) 2.3.4.2.9 Fixing accessories and mounting 2.3.4.2.10 Galvanizing 2.3.4.3 RATINGS System Rated Voltage and Frequency Nominal discharge current



Line discharge class Continuous operating voltage Creepage distance of insulator Insulation level of housing Lightning impulse residual voltage Maximum residual voltage at :

10 kA 1/2 µs 5 kA 8/20 µs 10 kA 8/20 µs 20 kA 8/20 µs 40 kA 8/20 µs 500 A 30/60 µs 1 kA 30/60 µs 2 kA 30/60 µs Temporary overvoltage for 1 s Temporary overvoltage for 10 s Energy discharge capability - thermal Energy discharge capability - impulse Cantilever load, dynamic

2.3.5.2 List of Type Test Reports submitted (indicate Test Report Numbers, Testing Authority and Contact Addresses)

2.3.5.3 List of Tests to be witnessed by KPLC Engineers at the factory

2.3.6 Marking Packing Manufacturer’s Guarantee and Warranty List of catalogues, brochures, drawings,

technical data, test reports and customer sales records submitted to support the offer.

STATEMENT OF COMPLIANCE TO SPECIFICATION


3.8 33KV SURGE ARRESTORS (DIVERTERS)

Description Bidder’s offer

Manufacturer, Country of origin of surge arresters offered Type Reference No./Model No. Service Conditions



System Information

Highest Voltage of Equipment (Um) Basic Insulation Level (BIL) Maximum altitude of installation (a.s.l.) Neutral system earthing Maximum ambient temperature Power Frequency Electrical data

Applicable Standard Rated voltage (Ur) Maximum continuous operating voltage (Uc / MCOV) Nominal discharge current (In, 8/20 µs) Line discharge class Long duration impulse current withstand (2 ms) High current impulse withstand (4/10 µs) Rated short circuit current (0,2 s) Maximum residual voltage at : 10 kA 1/2 µs 5 kA 8/20 µs 10 kA 8/20 µs 20 kA 8/20 µs 40 kA 8/20 µs 500 A 30/60 µs 1 kA 30/60 µs 2 kA 30/60 µs Temporary overvoltage for 1 s Temporary overvoltage for 10 s Energy discharge capability - thermal Energy discharge capability - impulse Power Frequency withstand voltage (1min, wet), arrester complete

Lightning Impulse withstand voltage (1.2/50 µs), arrester complete

Mechanical data

Minimum creepage distance Cantilever load, dynamic Construction Housing List of Type Test Reports submitted (indicate Test Report Numbers, Testing Authority and Contact Addresses). Accreditation certificate (ISO/IEC 17025) for the laboratory is required

List of Tests to be witnessed by KPLC Engineers at the factory

Marking (list parameters to be marked and method of marking to be used on surge arresters manufactured for KPLC)

Packing Manufacturer’s Guarantee and Warranty



List of catalogues, brochures, drawings, technical data, test reports and customer sales records submitted to support the offer.

STATEMENT OF COMPLIANCE TO SPECIFICATION


Note: This schedule does not in any way substitute for detailed information required elsewhere in the specification.

3.9 66KV 400MMSQ SINGLE CORE XLPE COPPER CABLE – NOT REQUIRED