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220 kV GAS INSULATED SWITCHGEAR

1.0 DESIGN CRITERIA

1.1.0 SYSTEM PARAMETERS 220 kV GIS

Sl.No. Parameter Value1) Voltage (Nom. /Max.). KV 220 kV + / - 10%

2) Frequency Hz % 50 5%

3) Fault Level kA rms 40

4) System earthing Solidly earthed

5) Short-time current rating (for allcurrent carrying parts)

40 kA for 3 seconds

6) Basic Insulation Level kVP 1050

7) Power frequency withstand voltage

kV rms Dry/Wet

460 kV (RMS)

8) Maximum radio interferencevoltage level at 1 MHz & 266 KVrms phase to ground voltage ,micro volts

1000

9) Minimum clearances in air

a) Phase to Phase, mm 2400

b) Phase to Earth, mm 2100

10) Safety Clearances

a) Safety working clearances, mm 5000

11) Creepage distance mm for SF6 toair bushing at max. voltage 31 mm/kV

12) Auxiliary Power Supply

a) A.C. System 415 V, 3 phase/240V, 1 phase

b) D.C. System 220V

c) UPS 240V

1.2.0 RATINGS AND REQUIREMENTS

The ratings and electrical characteristics of the complete GISshall be as given hereunder. The ratings applicable to specificitems of equipment are included in the relevant clauses dealing withthat equipment.

Type of GIS Single phase enclosed switchgear for 220KV.

1) Location Indoor

2) Maximum ambient temperature 50 Deg C3) Nominal voltage class, kV rms 220 KV

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4) Rated voltage, kV 245 KV5) Rated frequency, Hz 506) Number of phases 37) Number of busbars 38) Rated normal current at 50 Hz, A, rms 2000A9) Rated short circuit current at rated

maximum voltage, kA

not less than 40 kA,

rms (symmetrical) for 3sec.10) Lightning impulse withstand voltage

(phase to phase and phase to earth)at minimum operating gas pressure

1050 kV

11) 1 Minute power frequency withstandvoltage, kV, rms

460 KV

12) Rated peak withstand current, kA crest 10013) Material of enclosure Aluminium Alloy14) Material of busbar Copper/Aluminium Alloy15) Insulation medium SF6

16) Leakage rate of SF6 per annum for eachcompartment

0.5% or less

17) Partial Discharge Level, pc 5 or less at 1.5 Un/318) Noise Level (Less than) 48 dB19) Degree of Protection IP 6520) Max. SF6 Operating pressure 10.5 Bar (Hg)21) Rated Auxiliary supply voltage 220 V D.C/415 V, 3

phase /240 V, singlePhase 50 Hz A.C.

All current carrying components of the equipment specified shall be

capable of continuous operation at the specified rated current withoutexceeding the maximum temperature rises specified in the relevant IECstandards.

Thermal calculations shall be based on the climatic conditions given inproject information furnished in Vol-1A.

1.3.0 220 kV High Voltage Outdoor Bushing (Porcelain Type)

Sl.No. Item Unit Required

1 Applicable standards IEC 60137 , 61463

2 Operating voltage (U0/U) kV 220

3 Rated voltage kV 245

4 Rated short-circuit withstandcurrent

kA/3 sec 40

5 Rated peak withstand current kA 100

6 Insulation medium SF6

7 Material of enclosures Porcelain

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8 Lightning impulse withstandvoltage (peak) (phase to phase andphase to earth) at minimum

kV 1050

9 Power frequency withstand voltage(1 min.) (phase to phase andphase to earth) at minimum

operating gas pressure

kV 460

10 Rated current at 50C A 2000

11 Creepage distance at rated voltage mm/kV 31

1.4.0 220 kV High Voltage Outdoor Bushing (Polymer Type)

Sl. No Item Unit Required

1 Applicable standards IEC 60137, 61463

2 Operating voltage (U0/U) kV 220

3 Rated voltage kV 245

4 Rated short-circuit withstandcurrent

kA/3 sec 40

5 Rated peak withstand current KA 100

6 Insulation medium SF6

7 Material of enclosures Polymer

8 Lightning impulse withstandvoltage (peak) (phase to

phase and phase to earth) atminimum operating gas

kV 1050

9 Power frequency withstandvoltage (phase to phase andphase to earth) at minimumoperating gas pressure

kV 460

10 Rated current at 50C A 2000

11 Creepage distance at rated mm/kV 31

2.0 TECHNICAL SPECIFICATION

2.1.0 All the equipment, material etc. to be supplied shall be new and of thebest quality and shall conform to the specification given here under. Allsimilar materials and removable parts shall be uniform andinterchangeable with one another.

2.2.0 Lightning arresters for GTs, ICTs and outgoing lines shall be mountedon a structure placed near the respective equipment.

2.3.0 The switchgear shall be of compact and modular design, fully metal-clad and of the sulphur-hexafluoride (SF6) insulated type. It shall beconstructed for the indicated busbar system, and shall include allnecessary switches and current and voltage transformers, as detailedin the respective tender drawings. The switchgear shall be supplied

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complete with all auxiliary equipment necessary for operation,routine maintenance, repairs or extensions.

2.4.0 The switchgear shall be designed for continuous operation under allsystem operating conditions including sudden change of load andvoltage and short circuits within its ratings. The equipment shall be

designed to withstand normal operating voltage even if the inside gaspressure decreases to atmospheric pressure as long as no switchingoperations are performed.

2.5.0 Components that may require to be renewed and standard assembliesthat may be transferred from one circuit to another, shall beinterchangeable and where required this shall be demonstrated by theBidder/Contractor.

2.6.0 The arrangement of the switchgear shall be such as to enabledismantling a bay without affecting the adjacent bay. However, toremove the busbar disconnector, a shut down of the relevant section ofthe busbar will be required.

2.7.0 To secure minimum time of repair, all driving mechanisms of CircuitBreakers, Disconnectors and Earth Switches shall be respectivelyinterchangeable to those of similar other feeders and/or spare partsshall comprise complete units.

2.8.0 The switchgear shall be constructed of suitable material and thicknessto withstand the mechanical and thermal stresses due to shortcircuits and internal arc faults. For the rated duration of short circuitreference shall be made to the design criteria.

2.9.0 Not withstanding scope of supply mentioned in Cl. No. 2.0 of Section-2,if any equipment, tools, or instruments are considered essential forcompletion, the same shall also be supplied.

2.10.0 The enclosure and seals shall be designed to withstand the gaspressure encountered under normal and short circuit conditions. Thethickness of the enclosures shall be in compliance with IEC60517.

2.11.0 Viewing windows shall be provided at the disconnectors and earthingswitches to ensure that each contact position can be inspected. Each

section shall have plug-in or easily removable connection pieces toallow for easy replacement of any component with the minimum ofdisturbance to the remainder of the equipment.

2.12.0 Materials used in the manufacture of the switchgear equipment shallbe of the type, composition and physical properties best suited totheir particular purposes and in accordance with the latestengineering practices. All joint surfaces shall be machined, and allcastings shall be spot faced for all bolt heads or nuts and washers. Allscrews, bolts, studs and nuts shall conform to metric system.

2.12.0 Each pressure filled enclosure shall be designed and fabricated tocomply with the requirements of the applicable pressure vessel

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codes of the country of origin and based on the design temperatureand design pressures as defined in IEC 517.

2.14.0 The initial gas filling of the switchgear and sufficient extra SF6 gas forcompensation of possible losses during installation and service for 20years shall be supplied. A wheeled maintenance device shall be

supplied with pressure vessel, vacuum pump and all required gaugesand fittings for the service of the switchgear. Manufacturer shallguarantee that the pressure loss within each individual gas filledcompartment will not be more than 0.5 percent per year.

2.15.0 Each gas filled compartment shall be equipped with static filters. Thesefilters shall be capable of absorbing any water vapour, which maypenetrate into the enclosures.

2.16.0 The switchgear line-up, when installed and operating under theambient conditions shall perform satisfactorily and safety under allnormal and fault condition. Even repeated operations upto thepermissible servicing intervals, under full rated fault conditions, shallnot lead to diminished performance or significantly shortened usefullife of the switchgear. Arc faults caused by external reasons shall bepositively confined to the originating compartment and shall notspread to other parts of the switchgear. Routine replacement ofinsulating gas shall not be required in intervals of less than ten years.

2.17.0 Temperature rise of current carrying parts shall be limited to thevalues stipulated in IEC 60694, under rated current and the climaticconditions at site. The temperature rise for accessible enclosure shallnot exceed 20C at an ambient air temperature not exceeding 50C.In the case of enclosures, which are accessible but need not betouched during normal operation, the temperature rise limit may bepermitted upto 30C.

2.18.0 Bracing shall be provided for all mechanical components against theeffects of short circuit currents specified under system parameter.The design of the equipment shall be such that the agreed permittedmovement of foundations or thermal effects do not impair theassigned performance of the equipment.

2.19.0 Thermal rating for all current carrying parts shall be a minimum of 3

sec. at rated voltage for the rated symmetrical short-circuit current. Ifthe max. short circuit time is extended, the I2xt value shall remainconstant.

2.20.0 The switchgear shall be of free-standing, self-supporting dead-frontdesign, with all high-voltage equipment installed inside the gas-insulated, metallic earthed enclosures, and suitably sub-divided intoindividual arc and gas-proof compartments, at least for

* busbar section with associated busbar disconnector

* Circuit breaker

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* Line disconnectors

2.21.0 The busbars shall be sub-divided into compartments including theassociated busbar disconnectors.

2.22.0 Arrangement of the individual switchgear bays shall be such as to

achieve optimum space-saving, neat and logical arrangement, andadequate accessibility to all external components.

2.23.0 Each line up of switchgear shall be suitable, and prepared for futureextension on either end without any drilling, cutting or welding onthe existing equipment. To add equipment, it shall not be necessaryto move or dislocate the existing switchgear bays.

2.24.0 For routine inspections and possible repairs, all elements shall beaccessible without removing support structures. The removal ofindividual enclosure parts, or entire breaker bays, shall be possiblewithout disturbing the enclosure of neighbouring bays.

2.25.0 It shall be impossible to touch live parts of the switchgear unwillingly,i.e. without the use of tools or brute force, or to perform operationsthat lead to arcing faults.

2.26.0 The primary design goal shall be the avoidance of all known reasonsfor internal arcing. Should it occur, nevertheless, the release ofpressurized gas into the atmosphere must occur in such acontrolled way that personnel standing at the operating position ofthe switchgear will not be hurt directly in the process. Further more,no part of the enclosure, or any loose parts, may fly off theswitchgear in such an event, and no holes may burn through theenclosure until the nearest protective relay has tripped. Allearthing connections must remain operational during and after an arcfault.

2.27.0 All interlocks that prevent potentially dangerous mal-operations, shallbe constructed such that they cannot be defeated easily, i.e. theoperator must use tools or brute force to over-ride them.

2.28.0 The actual position of disconnector and grounding switches shall bepositively displayed by means of reliable optical indicators visible from

the operating position.

2.29.0 Counter measures against expansion, vibration and noise

2.30.0 The GIS equipment shall be furnished with specially designedstainless steel compensators/bellows to preserve the mechanicalstrength of the equipment at the connection portions to deal with thefollowing problems:

a) To absorb the expansion and Contraction of outer enclosureand conductor due to temperature variations.

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c) To absorb the vibration of the transformer and switchingequipment

d) To absorb the dimensional variations due to uneven settling offoundation

e) To withstand seismic forces as mentioned in climatic condition.

3.0 EQUIPMENT SPECIFICATION

3.1.0 GIS Equipment and Accessories

3.1.1 Circuit Breakers

a) Each circuit breaker shall comprise of three metal clad breakerpoles. They shall be designed for installation in SF 6 gas -insulated metal clad switchgear, and shall use SF 6 gas forboth insulation and arc quenching.

b) The circuit breakers shall be horizontal mounted and shallwithstand the forces imposed by the earthquake requirementsstated under Section-2 Volume 1A.

c) Breaker shall be suitable for following switching duties:

* Terminal faults

* Short line faults

* Out of phase switching

* Interruption of small inductive current includingtransformer magnetizing inrush currents.

* Interruption of line charging currents.

The breaker switching under above switching operations shallnot result in excessive over voltages and/or restrike of arc.

d) Breaker components shall meet Partial Discharge requirementas indicated in Design Criteria.

e) The circuit breakers shall be designed to withstand the highstresses imposed on them during fault clearing, load rejection,out-of-phase switching, re-energization of lines with trappedcharge and perform make and break operations as per thestipulated duty cycles satisfactorily.

f) Spring Operating Mechanism / Pneumatic / Hydraulic, one foreach pole, shall be employed for closing and tripping the circuit

breakers. 220 V DC will be used for control / tripping.

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g) The circuit breakers shall have local storage sufficient for aduty cycle of O-0.3 seconds-CO- 3min-CO following the loss ofsupply to the main energy storage system.

h) The circuit breakers shall be trip-free and have anti-pumpingand phase disagreement protection. There shall be two trip

coils per pole of the breakers.

i) Circuit breakers shall have single-phase auto-reclosingcapabilities. The breakers shall be capable of independent poleoperation. Each phase shall be completely isolated from theother two phases.

j) Each circuit breaker pole shall be equipped with a localenclosed-type mechanical position indicator clearly visiblefrom the breaker front, together with remote position indicatoron the bay module control cabinet, and remotely at the powerhouse/ switchyard control room. The mechanical indicatorwording and colouring shall be as follows:

Sign Background Colour

Open position Open Green

Closed position Closed Red

k) The circuit breakers shall be interlocked electrically with theirassociated disconnectors such that the disconnector cannotbe opened or closed unless the associated circuit breakers areopen. The interlocking shall prevent any incorrect switchingsequence and enable the breakers to be operated withoutrisk, either from the local bay module control cabinet orfrom the switchyard control room. Actuation of the manualoperating device shall also disable the electrical controlcircuits. Interlocks shall be provided to prevent hunting andother dangerous or undesirable operations of the circuitbreaker.

l) The circuit breaker control system shall inhibit tripping orclosing of the circuit breaker when there is insufficient stored

energy in the operating mechanism storage cylinder or if SF6density drops below a minimum permissible level. The state ofthe breaker arc quenching and insulating gas shall bemonitored by a temperature-compensated density switchwith two alarm levels. The first stage alarm shall be set wellbefore any dangerous condition is reached, the second stageshall inhibit breaker operation.

m) The circuit breakers shall be capable of being operated locallyor from remote. Local operation shall be by means of anopen/close control switch located in the bay module control

cabinet. Remote control via a remote/local control transferswitch shall be from the power house/ Switchyard control

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room. Protection trips shall remain operable in eitherremote or local control mode. When in the maintenancemode, all remote trip or close control signals shall be blocked.The breaker controls shall operate from the 220 V DC systemwith both the trip coils connected. A manually operated trippingdevice shall also be provided with each breaker, which can be

operated in an emergency or during maintenance. Mechanicalindicators coupled to the moving contact system shall beprovided to show the true position of the main breakercontacts. Operating counters shall be provided for eachbreaker pole or otherwise for each breaker.

n) The selected circuit breakers must be suitable for their intendedservice and location for all no load, full load and fault serviceconditions.

o) The inspection of breaker contact in service shall be carriedout after 3000 to 4000 operating cycles and after a cumulative

interruption of 20 Nos. at rated short circuit current.

3.1.2 Current Transformers

a) The current transformers, incorporated into the GIS, shall beused for protective relaying and metering and shall be ringtype, fitted externally to the supporting enclosure. The CTsshall have multicores with multi-ratio, which shall bechangeable by means of taps on the secondary side. Thesecondary leads shall be brought out into the secondaryterminal box. All current transformers shall have effective

electromagnetic shields to protect against high frequencytransients.

b) CT shall have a short time primary current rating not less thanthat of the associated switchgear. Secondary windings of each CTshall be earthed at one point only. The thermal rating of thecurrent transformer shall allow, at site conditions, a 20%continuous overloading referred to nominal rating of the currenttransformer.

c) All transformers are to be provided with an identifying label

giving manufacturer, type, ratio, class, output and serial number.

d) Where multiple ratio secondary windings are executed, theabove-mentioned label shall clearly indicate the terminalconnection required for each ratio, and they must be clearlyindicated on the appropriate diagrams and drawings.

e) The minimum rated output of CT's shall be 20 VA or otherwiseapproved, based on the stability calculations to be submittedfor approval by the Bidder/Contractor. The magnetising curvesfor each CT protection cores shall also be submitted for approval.

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f) To guarantee the correct protection relay operation, through-fault stability calculations shall be submitted showing thecorrectness of the chosen CT core, i.e. rated output, class ofaccuracy, rated accuracy limit factors, the rated primarycurrent, turns ratio, knee-point e.m.f. and resistance of thesecondary windings (corrected to the maximum service

temperature).

h) Suitable provision shall be made for primary current injectiontesting of current transformer circuits.

g) A current transformer marshalling terminal box for all thethree phase current transformers shall be provided, outside theenclosure for connections of all cores. The marshalling boxshall be used for the star/delta configuration.

3.1.3 Voltage Transformers

a) SF6 insulated voltage transformers shall be of the inductive type,constructed and tested in accordance with IEC-60044-2. Theyshall be fully encapsulated. The gas compartment shall besegregated from the adjacent compartments. Minimum ratedoutput shall be 100 VA, if not specified or approved otherwise

b) The thermal rating of the voltage transformer shall allow, at siteconditions, a 20% continuous overloading and 50%overloading for 30 seconds with reference to the nominal ratingof the voltage transformer.

c) The busbar VT's shall be connected through hand-operatedisolators, which are to be provided with padlock facilities &padlocks.

d) Furthermore, to allow the testing of cables without the removalof a V.T., disconnection facilities shall be provided.

e) Secondary circuits shall be suitably supervised by MCB's ofadequate characteristics.

f) The V.T. gas compartment shall be isolated from the adjacent

gas compartments with separate gas supervision. If the V.T. gascompartment is connected to the line isolator gas compartmenta non-return valve shall be provided to avoid entering of anydecomposed gas from the isolator gas compartment to the V.T.gas compartment.

g) The bus voltage transformers shall be located in a separatebay module on the bus, and shall be connected phase-to-ground to the phase buses and shall be used forprotection, metering and synchronizing.

h) Provision for short circuit and overload protection for voltagetransformers against external short circuit shall be made. The

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same shall be installed in a separate marshalling box or controlcabinet.

3.1.4 Disconnecting Switches

a) The disconnecting switches shall be of the 3-phase, single-pole,

group operated type, installed in the switchgear, in locationsas shown on the single-line diagram, to provide electricalisolation of the circuit breakers from the transformer, doublebus and transmission lines. The disconnectors shall be electricmotor operated, and shall be equipped with a manual operatingmechanism for emergency use.

b) The disconnecting switches shall have breaking capabilities asper IEC requirements. Contact shielding shall be designed toprevent restrikes and high local stresses caused by the transientrecovery voltages when currents are interrupted.

c) The switch operating mechanisms shall be complete with allnecessary linkages, clamps, couplings, operating rods,support brackets and grounding devices. All bearings shall bepermanently lubricated or shall be such that no lubricationor maintenance is required.

d) Opening and closing of the disconnectors shall be either by localor remote control. Local operation shall be by means of a two-position control switch located in the bay module controlcabinet

e) Remote control through the Remote/Local transfer switch shallbe from the Switchyard control room.

f) The disconnector operation shall be interlocked electrically withthe associated circuit breakers such that the disconnectorcontrol is inoperative if the circuit breaker is closed. Actuationof the emergency manual operating device shall also disablethe electrical control. Disconnectors in open condition shall besecured against reclosure.

g) Each disconnector switch shall be supplied with 6 NO and 6 NC

auxiliary switches for use by others, over and above thoserequired for switchgear interlocking purposes.

h) Signaling of the disconnector closed position shall not takeplace unless it is certain that the movable contacts has reacheda position in which the rated normal current, peak withstandcurrent and short-time withstand current can be carried safely.

i) Signaling of the disconnector open position shall not take placeunless the movable contacts have reached a position such thatthe clearance between the contacts is at least 80 percent of

the rated isolating distance.

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j) The auxiliary switches and auxiliary circuits shall be capable ofcarrying a current of at least 10 A DC continuously.

k) Auxiliary switches shall be capable of breaking at least 0.2 A ina 220 V DC circuit, with a time constant of not less than 20milliseconds. Auxiliary switches shall be positively driven in

both directions.

l) Disconnecting switches and adjacent safety groundingswitches shall have electrical interlocks to prevent closure ofthe grounding switches when the disconnecting switches arein the closed position and to prevent closure of thedisconnecting switch when the grounding switch is in the closedposition. The disconnector shall be pad lockable in the close &open position.

m) Disconnecting switches having adjacent high-speed faultmaking grounding switches shall be interlocked such that thefault making switches close first to discharge the linecharging currents before the respective disconnectors may beopened.

n) When the lines are taken out of service for maintenance, etc.,the disconnectors and high-speed grounding switcheslocated on the transmission line feeder modules of the GISswitchgear are required to operate as follows:

o) After tripping of circuit breaker, operation of the respectivedisconnector control switch to open will first initiate rapidclosure of the associated high-speed grounding switch. Whenthis grounding switch is signaled 'closed by its auxiliaryswitches, an adjustable time delay relay will start to allow timefor any trapped charges to dissipate into the groundingnetwork. After the set time delay, the disconnector motoroperating mechanism will be energized to open thedisconnector.

p) Operation of the disconnector control switch to close will closethe disconnector, which -when proved 'closed , will signal thehigh-speed ground switch 'to open .

q) Local control of the disconnectors and high-speed groundingswitches from the bay module control panel shall be fromindividual control switches with the Remote/Local transferswitch set to' Local.

r) All electrical sequence interlocks shall apply in both Remote andLocal control modes but in local mode the time delay relay shallbe blocked.

s) Each disconnector switch shall have a clearly identifiable local,

positively driven mechanical position indicator, together withremote position indicator on the bay module control cabinet and

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remotely in the powerhouse / switchyard control room. Theindicator shall have the following wording and colouring:

Sign BackgroundcoloursOpen position Open GreenClosed position Closed Red

t) Each disconnector shall be fitted with an optical indicator per polelocated between the pole and the driving rod so that theopen or closed contacts of the disconnector are visible fromthe floor level.

3.1.5 Maintenance Earthing Switches

a) Three-pole, group-operated, work-in-progress maintenanceearthing switches shall be provided as shown on the single-linediagram. Each earthing switch group shall be electric motor(DC) operated. Means of emergency manual operation shall

also be provided.

b) In order to provide test facilities, certain earthing switches mayrequire to be insulated from the enclosures and have easilyremovable ground connections.

c) Each maintenance-earthing switch shall be electricallyinterlocked with its associated disconnecting switch and circuitbreaker such that it can only be closed if both the circuitbreaker and disconnecting switch are open. Once closed it shallbe secured against reopening.

d) Maintenance earthing switch shall be operable locally from thebay module control cabinet only.

e) Positive mechanical position indication shall be provided locallyat each switch and remotely at each bay module controlcabinet, and in the control room. The indicator shall have thefollowing wording and coloring:

Sign Background Colour

Open position Open GreenClosed position Closed Red

u) Each earth switch shall be fitted with an optical indicator per polelocated between the pole and the driving rod so that theopen or closed contacts of the earth switch are visible fromthe floor level.

f) Interlocks shall be provided such that manual operation of theswitches or insertion of the manual operating device willdisable the electrical control circuits.

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g) Each earthing switch shall be fitted with 4 NO and 4 NCauxiliary switches for use by others, over and above thoserequired for local interlocking and position indication purposes.

h) Provision shall be made for padlocking the earthing switches ineither the open or closed positions.

i) All portions of the earthing switch and operating mechanismrequiring grounding shall be connected together utilisingflexible copper conductors having a minimum cross-sectionalarea of 50 mm2.

j) On opening, the line earthing switch should be able to breakcurrent induced by parallel lines according to IEC provisions.

k) The maintenance earthing switches shall conform to therequirements of IEC 129.

3.1.6 Fast Acting Earthing Switches

a) Fast acting earthing switches shall be located at the busbar andat all external HV connections of feeders like HV cables oroverhead lines or transformer connections. The switchingcapability shall be 200 A inductive at 25 kV and 25 A capacitive at25 kV.

b) Fast acting earthing switch shall be single pole operated with onemotor operated mechanism per single pole position. They shallalso have facility for emergency manual operation and thenecessary operating handles or hand cranks shall be supplied.

c) The switches shall be fitted with a stored energy closing system toprovide fault-making capability.

d) The short-circuit making current rating of each ground switchshall be at least equal to its peak withstand current rating.

e) Each switch shall have a positive local mechanical positionindicator and a remote indicator at the bay module controlcabinet, and in the powerhouse / switchyard control room. The

indicator wording and colouring shall be as follows:

Sign Background Colouri) Open position Open Greenii) Closed position Closed Red

f) High-speed ground switch operation shall be done locally fromthe bay module control cabinet, or remotely from the switchyard control room in conjunction with opening of theassociated disconnector switch.

g) These high-speed grounding switches shall be electricallyinterlocked with their associated circuit breakers such that the

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grounding switches cannot be closed if the circuit breakers areclosed. The grounding switches shall be required to close beforethe disconnector switches are opened in order to dissipate thetrapped charges, when the lines are taken out of service formaintenance, etc.

h) Interlocks shall be provided such that insertion of the manualoperating devices will disable the electrical control circuits.

i) Each high-speed grounding switch shall be fitted with 4 NO and 4NC auxiliary switches for use by others, over and above thoserequired for local interlocking and position indication. Allcontacts shall be wired to terminal blocks in the local bay controlcabinet. Provision shall be made for padlocking the groundingswitches in either the open or closed position.

j) All portions of the grounding switches and operating mechanismrequiring connection to ground shall be connected togetherutilizing flexible copper conductor having a minimum cross-sectional area of 50 mm2.

k) The high-speed make proof grounding switches shall conform tothe requirement of IEC 129.

3.1.7 Surge Arresters

a) Surge arrester shall be of SF6 gas insulated, metal enclosed,gapless metal oxide, heavy duty, station type.

b) The surge arrester shall successfully drain the dynamic currentsrepeatedly caused by impulse waves. The ground connectionshall be sized for the fault level of the GIS.

c) The arrester tanks shall be vertically or horizontally mounted tobest suit Manufacturer's switchgear layout, and shall be fittedwith pressure relief vents directed away from areasfrequently used by operating personnel. Each arrester unitshall be fitted with a discharge counter located in an easilyaccessible position.

3.1.8 GIS Termination Arrangement

a) Outdoor SF6 bushings, for the connection between the GIS andoverhead lines or conventional air insulated equipment shall befurnished where specified.

b) Bushing shall comply with the relevant IEC standards. Thebushing can be with composite insulators (Silicon rubber) orwith porcelain insulators with all surfaces free fromimperfection. The internal and external electrical field of thebushings can be controlled by a capacitive grading body or

by grading shields.

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c) For SF6/Air bushings, the GIS manufacturer shall providedetailed drawings and information.

3.1.9 Bus bars and Bus Ducts

a) The SF6 single-phase/three phase encapsulated busbars and

busducts shall be mounted in horizontal/verticalconfiguration to suit the switchgear layout and shall be singlephase encapsulated.

b) The conductors of the busbars shall be fabricated of AluminumAlloy tubular sections with cross sectional area suitable to meetthe current rating requirements. The tubular bus sections shallbe housed in an aluminum enclosure, filled with pressurized SF6gas. The conductors shall be supported from the enclosures byhomogeneous epoxy resin insulators shaped to ensure uniformelectrical field distribution at rated voltage. Adequate provisionshall be made for absorption of thermal expansion of theconductors and of differential thermal expansion between theconductors and the enclosures. Metal bellow typecompensators with adjustable tensions shall be provided,where required. The enclosures shall be designed to eliminateas much as possible all external effects of the flux created bynormal and fault currents. The power losses in the systemshall be kept to a minimum, and induced voltages on theenclosures shall not be allowed to exceed reasonable limitsof safety for operating personnel. The Supplier shall furnishsupporting calculations in respect of induced voltage andlosses guaranteed for the enclosure.

c) Bus end connections shall be made with multi-contactconnectors to allow for axial thermal expansion of thebus. Enclosure end connections shall be flanged, and shall befitted with gaskets or O-ring seals to provide an effectivegastight joint between sections.

d) The common point of the two busbars should be in aseparate enclosure with an earthing switch in order to ensureavailability of one busbar in service at all times.

e) Each end of the busbars shall be designed for convenientfuture extension of the switchgear. Bus conductor endconnectors and enclosure flanges shall be designed accordingly.

f) All necessary steel supporting structures required for propererection, the manufacturer shall provide leveling andalignment of the busbars and bus ducts.

g) In order to provide an improved dielectric withstandcapacity, the interior of enclosures may not be required to bepainted.

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a) Manufacturer shall supply all equipment supporting structures,required access ladders / stairway/ walkways, transverse andlongitudinal beams and supporting members, completewith all necessary hardware. Any temporary scaffolding or amovable platform, required for maintenance, shall also be

supplied.

b) All steel structure members shall be hot-dip galvanized afterfabrication. All field assembly joints shall be bolted. Fieldwelding shall not be acceptable.

c) Non-corrosive metal or plated steel shall be used for boltsand nuts throughout the work. Manufacturer shall providesuitable foundation channels and anchor bolts to support theswitchgear assemblies. All mounting bolts, nuts andwashers shall be provided to fasten the switchgear baseframes to the foundation channels.

d) Foundation channels and anchor bolts shall be installed inthe civil works in accordance with instructions provided bymanufacturer.

3.1.11 Insulating Gas

a) The SF6 gas required for first filling shall be furnishedwith the switchgear, along with connecting hose and fittings.

b) Characteristics

SF6 gas to be filled in GIS shall in all respect conform to thefollowing values (in accordance with IEC Publication no. 60376):

Impurity Max allowable concentration(by weight)

Air 0.05% CF4 0.05% Moisture 15ppm

Hydrolysable fluorides expressed as HF 1.0 ppm

During commissioning the dew point of SF6 gas shall be

measured and documented.

c) Gas System

The gas pressure shall be based on the design. The gassystem shall be independently separated into logical groupsto provide the largest practical gas reservoir for least leaks,but small enough to permit optimum installation, maintenanceand leak detection procedures.

The independent gas section shall be separated by gas-tight

barriers, capable of withstanding full pressure from eitherside with a vacuum on the opposite side.

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d) Gas Monitoring Devices

Temperature- compensated gas density monitoring devicesshall be provided for each gas compartment. The devicesshall provide continuous and automatic monitoring of the

density of the gas. The monitoring device shall have twoalarm settings. These shall be set so that:

i) Advance warning can be given that the gas densityis unacceptably low.

ii) After an urgent alarm, measures can be taken toimmediately isolate the particular compartment electricallyby tripping circuit breakers and opening disconnectswitches.

3.1.12 Mobile SF6 Gas Handling equipment

a) Two nos. SF6 gas processing units suitable for evacuating,liquifying, evaporating, filling, drying and purifying SF6 gasduring the initial installation, subsequent maintenance andfuture extension of GIS, shall be provided. The cart shall beequipped with rubber wheels and shall be easilymaneuverable by two workers within the GIS building.

b) The unit shall be self-contained (except for additional gasstorage bottles and external power supply at 415 V AC, 3-phase, 50 Hz) and fully equipped with an electric vacuumpump, gas compressor, gas drier, gas filter, refrigerationunit, evaporator, gas storage tank, full instrumentation formeasuring vacuum, compressor inlet temperature, tankpressure and temperature, valving and piping to performthe following operations as a minimum requirement:

* Evacuation from a gas filled compartment using thevacuum pump

* Transfer of SF6 gas from a system at some positive ornegative pressure to the storage tank via the gas drier and

filter

* Recirculation of SF6 gas in the storage tank through thedrier

* Recirculation of SF6 gas in any switchgear or bus ductcompartment through the drier and filter

* Evaporating and filling SF6 gas

* Drawing off and liquefying SF6 gas

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system and evacuating a second gas system using thevacuum pump

c) Adequate length of hoses shall be provided for filling of SF6 gasin any of the gas compartment with the help of gas cart.

3.1.13 Corona

In general the contours of energized metal parts of the GIS andany other accessory shall be such as to eliminate areas or pointsof high electrostatic flux concentrations. Surfaces shall besmooth with no projection or irregularities, which may causecorona.

3.1.14 Fire Retardancy

All components shall be fire retardant and shall be tested inaccordance with IEC 695. Gas emissivity when the material isheated shall be minimal. PVC material shall not be used but fireretardant cables as per IEC 332-1 may be used.

Control wire in a grouped environment shall not convey flame,continue to burn when tested as per IEC 695. The method of testand criteria for success or failure shall be in accordance with the aboveIEC.

3.1.15 High Voltage Transients

High Voltage Transients from switching operations and internalfaults are coupled to the external sheath of GIS. Since the effects ofthese transients on people are not known, operation personnel arerequired to avoid contact with the sheath during switchingoperations. Such a restriction is considered undesirable, and theSupplier may therefore provide devices and techniques, which mayreduce such hazard or new techniques to reduce transients to anacceptable safe level.

3.1.16 Service Life

SF6 Circuit breakers disconnect switches and ground switches will

be subjected to frequent and occasionally repetitive, no loadoperations and switching offload, Capacitive and inductive currentwithin their ratings. In order to minimize maintenance andcomponent replacement, the Supplier shall submit proof andfurther guarantee that all offered SF6 GIS equipment has aminimum service life of 5,000 normal operations. The maintenancefree period for any of its external components shall not be lessthan 5 years intervals. Internal components including refilling ofgas shall not be less than 10 years. The Supplier shall propose therecommended period for schedule maintenance.

3.1.17 Grounding Of GIS

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a) GIS will be housed on GIS floor. The Contractor will alsoprovide under ground mat below the switchyard withadequate number of Mild steel risers.

The Supplier shall also supply entire material for groundbus of GIS viz. conductor, clamps, joints, operating and safety

platforms etc. to be laid/embedded in GIS floors. The Supplier isalso required to supply all earthing connectors and associatedhardware material for:

i) Connecting all GIS equipment, Busduct, enclosures, controlcabinets, supporting structures etc. to the ground bus ofGIS, and

ii) Connecting ground bus of GIS to the ground mat.

b) The grounding arrangement of GIS shall ensure that touchand step voltages are limited to safe values. The enclosures ofthe GIS shall be grounded at several points such that thereshall be a grounded cage around all live parts. The groundcontinuity between each enclosure shall be effective overflanges, with or without links or straps to bridge the flanges.Copper/Aluminum straps shall however bridge the metallicexpansion bellows.

c) Where operating mechanism cabinets are mounted on theswitchgear, the grounding shall be made by separateconductor. Local control cabinets and marshalling boxes shallbe grounded through a separate conductor.

d) All conduits and control cable sheaths shall be connectedto the control cabinet or marshalling box grounding bus. Allsteel structures shall be grounded.

e) Each removable section of catwalk shall be bolted to thesupport structure for ground continuity.

f) The enclosure grounding system shall be designed tominimize circulating currents and to ensure that thepotential rise during an external or internal fault is kept to

an acceptable level. The guidelines of IEEE Std. 80-1986 onGIS grounding, especially the transient ground potentialrise caused by high frequency phenomena, shall be takeninto consideration while designing the grounding system forGIS.

g) The manufacturer shall furnish readily accessible connectorsof sufficient mechanical strength to withstandelectromagnetic forces as well as capable of carrying theanticipated maximum fault current without overheating byat least from two paths to ground from the main ground

bus.

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h) Provisions of IEC 517 and IEC 694 regarding safeguards inearthing of connected cables, testing during maintenance andother safety measures shall be ensured.

3.1.18 Bay Module Control Cabinet

Indoor mounted, freestanding type Bay Module Control cabinets shallbe provided, one no. for each bay with IP55 degree of protection withneoprene gasket for all doors and openings.

Bay module control cabinet shall be provided with min. 300 terminalsand two subsections, viz, indicators for bay equipments, Terminal boxand auxiliary supply distribution box.

Terminal box: Providing intermediate termination of all auxiliarycontacts of breaker, isolator and earthing switches (whether used ornot) and preparing interlocking.

Auxiliary supply distribution box from where both AC auxiliary supply,heating / lighting supplies and DC auxiliary control supply will bedistributed to various motors of all CBs, isolators, earthing switch andequipment terminal boxes.

All terminals will be of Stud and Nut type and mounted on DINchannels.

The Bay Module control cabinet will also be provided with lockabledoors, panel illumination lamps with CFL and door switch, 15A powersocket with switch, space heater with thermostat switch.

All auxiliary contacts of the CBs, isolators and earthing switches willbe terminated in terminal box section of bay marshalling controlcabinets. All hardwired interlocking will be wired in the above box.

Provision for terminating one number of 3 phase, 4 wire AC, 50 Hzpower supply will be provided. Contacts for remote alarm for supplyfail will be provided.

Single phase, 240V, AC heating and lighting supply will be providedin loop in / loop out mode at bay marshalling cabinets. The heating

and lighting supply will be sub-distributed in radial way to provideheating and lighting supplies for all CT / PT marshalling boxes andeach bay marshalling control cabinets.

The scheme for all protections, controls, indications, interlocking,metering, AC distribution and all other schemes will be prepared insuch a way that cables will be laid in radial pattern. Loop formulationof cables shall be completely avoided.

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3.1.19 Control, Metering and Protection

a) Comprehensive controls, metering, protection alarm andindication shall be provided for switchyard equipment & system.

b) Electrical Relay panels shall be provided for 400 KV,switchyard and the same shall be located in the SwitchyardControl Room along with Bay controllers.

c) Each Bay Controller unit will control one circuit and associateddisconnecting switches, earth switches and instrumenttransformers along with bay mimic. The bay controller unitalong with numerical relay and protection panel, StationHMI shall be housed in air-conditioned Switchyard ControlRoom.

d) The objective of the protective system is to protect the equipmentfrom damage against fault detected in the equipment or in thesystem. The protection scheme shall be such as to protectthe equipment during system disturbance.

e) Automatic trip function will be initiated for isolation of

faults, which could cause immediate and severe damage.This isolation will also help maintaining the continuity ofsupply.

f) Every effort shall be made to avoid unnecessary tripping.Wherever possible, there will be annunciation to alert theoperator for taking corrective measure in time.

g) At least two protective devices operating in parallel ondifferent principles shall be utilized in protection of 400 KV Lines.

h) The bidder shall furnish with their offer a Single LineDiagram for Metering and Protection scheme of the400 kV and 220 kV Switchyard and a write-up on theOperation & Control Philosophy of the system.

3.2.0 Miscellaneous Switchyard Equipment &Accessories

3.2.1 Grounding Description

The tenderer shall design the grounding grid for the 400 kV switchyardso as to achieve the acceptable step and touch potentials as per IEC.Measurement of soil resistivity shall be part of the tenderers scope.Tenderer shall design the complete lightning protection system for the400 kV switchyard covering the gantry of 400 kV and 220 kV lines forconnection to GTs and STs respectively, provided in the transformeryard. The contractor shall coordinate with transformer package

contractor & TG package contractor respectively for interfacing of thelightning protection system and ground grid designs for the transformer

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yard, 400 kV and 220 kV switchyard. The grounding grid design shallconsider the following:

a) An underground grounding mat will be provided by vendor at adepth of 600 mm (minimum) within the 400 KV Switchyardto provide low impedance discharge path to earth for

lightning surge, switching surge and fault energy of thesystem. The risers at different location at a height of 300 mmfrom the ground level shall be provided for equipmentconnection.

The minimum ground conductor sizes to be used forunderground grounding mat shall be as follows:

Main ground conductor for : 40 mm dia M.S. rodunderground grounding mat

Ground Electrode : 3m length 40 mm dia M.S.rod

Risers for equipment connection: 40 mm dia M.S. rod

b) Connect all equipment and structures by using groundingconductor as indicated bellow

Over-ground grounding grid and: 75 x 12 mm GS flatequipment connection

Control & Relay Panels/ : 50 x 6 mm GS flatDistribution Boards etc.

c) Testing arrangements shall be provided at suitable locations.

d) Separate earthing pit/grounding arrangement for NumericalRelays and Switchyard Automation System (SAS) shall beincluded in tenderers scope.

e) Soil excavation and backfilling for ground grid shall be in thescope of bidder

3.2.2 Shielding

a) The Lightning Protection system shall be designed based on IS:2309.

b) In addition to providing Lightning Arrestors in TransformerYard, Lightning Masts are to be provided for 400 KVSwitchyard. Shielding wires of 7/8 galvanised steel wire (11Kg/sq.mm. quality) will be strung between Gantry supportsover the phase conductors. For 400 KV Lines shielding wireswill be strung between gantry towers. The complete

shielding network will be connected to the main groundmat of the Switchyard.

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c) The down conductors shall be 75 x 12 mm G.I. flat minimum.

d) Electrodes shall be provided at each connection point ofdown conductor and underground ground mat.

3.2.3 D.C. Supplies

a) Two sources of 220 V DC supplies shall be provided foressential functions such as Protection, Closing/Tripping,Alarms, Control, Emergency Lighting, Communication equipmentsetc. 48V DC supply shall be provided for PLCC System.

b) The batteries shall be Lead Acid Plante type along withaccessories with the cells assembled in suitable container.The racks for supporting battery cells shall be constructed ofbest quality teakwood, duly painted with at least (3) coats ofblack anti sulphuric acid paint. The batteries shall be installedin single tier and single/double row arrangement.

c) The battery capacity shall be decided considering thecriteria specified in the specification so that minimumpermissible voltage at load terminal is maintained withadequate margin for the total duty cycle.

Float and Float cum Boost Charger shall be static type,comprising SCRs connected in three-phase full wave fullcontrolled bridge circuit.

d) The charger rating and mode of operation shall be decidedbased on the stipulation given in the specification.

e) Battery and Battery Charger shall have SAS connectivity facility.

4.0 TESTING AND INSPECTION

4.1.0 General

a) All equipment, apparatus, materials and supplies providedunder this Contract shall be subject to tests in the shop in

the presence of the Owner/consultant and in the fieldunder the supervision of the Supplier, for ensuringconformity to the requirements of the specifications. Themethod and procedure of the tests for specified particularitems shall be submitted which shall be in conformity withone of the applicable recognised standards for making suchtests. Unless otherwise specified, manufacturer of theequipment shall perform all shop and field tests.

b) Manufacturer/Contractor shall submit a schedule of thespecified shop-testing program to the Purchaser for its

approval. Testing of related equipment shall becoordinated so that testing may proceed with minimum

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delay.

c) Manufacturer/contractor shall, at his own expense,promptly make good all defects evident by testing or madeapparent in any other way. After defects in the plant havebeen remedied, the plant will be subjected to such retesting

as may be necessary until the plant is proved to be insatisfactory operation.

d) Within 30 days of completion of each and every test requiredas proof of compliance with the specifications and/or each andevery specified test, including commissioning tests,manufacturer shall submit to the Owner six (6) signed copies ofa report covering such tests.

e) Test reports shall indicate the tests performed, the resultsobtained, instruments used, names of test personnel andprovisions for witnesses signatures. They shall also be numberedand dated. Format of these reports shall be submitted atthe same time as the test procedures specified above.

4.2.0 Factory Tests

A. Type Tests

Certificate of Type Tests carried out on similar equipmentshall be furnished. Evidence shall be given that the proposedswitchgear components to be supplied under this Contracthave been subjected to all type tests at an internationallyrecognised testing station, like KEMA or equivalent andapproved/ recognised by Owner If it deemed necessary,Owner will decide whether additional tests are necessary to beperformed.

The Bidder/Contractor shall submit type test certificatescovering the proposed switchgear components.

Type tests certificates/reports shall be considered acceptableif they are in compliance with the latest applicable relevantStandards (class "A" as per IEC Standards) and the following

:1. Type Tests conducted at an internationally recognised

Laboratory (KEMA or equivalent) acceptable to Owner.

2. Repeated Type Tests conducted at the manufacturer'slaboratory, witnessed by representatives from aninternationally recognised laboratory (KEMA orequivalent) and accepted by owner.

For the offered Circuit Breaker Type, type tests results ofalready executed tests shall be indicated in the concernedTechnical Data Sheet

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the above requirements, Owner reserves the right to ask forthe type tests to be repeated in the manufacturer's premisesor other places subject to the approval of Owner and at noadditional cost. These tests shall be performed in thepresence of an internationally recognised laboratory (KEMA orequivalent) and Owner. The internationally recognised

laboratory shall issue the relevant type test certificatesupon successful test.

The following tests shall be carried out as a minimum requirement:

1. Dielectric Test2. Temperature rise test3. Internal arc test4. Making and breaking tests5. Rated peak withstand current and rated short time

current tests on main and earthing circuits

6. Operation & mechanical endurance tests.

B. Routine Tests

All routine tests shall be witnessed by Purchaser/Consultant.

Switchgears and their components shall be subjected toroutine tests as per the latest relevant IEC recommendations.

Routine test certificates shall be submitted for Owner'sreview and approval before shipment of the switchgear

components.

Following tests shall be performed as routine tests inaddition to the standard tests:

* At least one local control cubicle (LCC) shall be testedtogether with the GIS during factory acceptance tests

* Speed and timing tests for circuit breakers

* Partial discharge measurements

* Chattering time of the arc contact shall bemeasured and recorded at no-load operations

* Visual inspection of the switchgear, in order to ensurethat all components are mechanically assembled andfixed properly and that there are no imperfections.

4.3.0 Site Tests

For site tests, the following shall be performed in particular:

* Speed and timing tests for circuit breakers

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* Timing tests for disconnectors and earthing switches

* Humidity/dew point measurement tests of SF6 gasduring commissioning, three months after that,before issuance of FAC, and at each refill operation.Critical dew points are subject to the approval of

Owner.

* Voltage drop tests during commissioning

* Functional interlocking tests

* Power frequency voltage test for switchgear andauxiliary circuits. The power frequency test (50 Hz)voltage shall be 65% of the rated voltage for existingbusbar extensions and 80% of rated voltage for newGIS.

* Gas leakage test on each bay with high sensitive gasleakage detector on all seals

* Partial discharge measurement for 400 kV ismandatory.

If applicable, the Bidder/Contractor shall prove that the HVcircuit breakers are capable of interrupting

* The capacitive current, and

* The inductive current

For switching of capacitors/shunt reactors under siteconditions, both by either performing the relevant tests orby submitting the relevant type test reports plus calculations,to the satisfaction of Owner.

The Bidder/Contractor shall furthermore advise andguarantee the minimum number of switching operations forthe conditions as mentioned above within the arrangement asdesigned by him.

5.0 DRAWINGS, DATA, INFORMATION AND MANUALS

Drawings, data, information and manuals shall be submittedas indicated below:

5.1.0 Along with the bid

* Electrical single line diagram showing metering, protectionscheme & a write-up on control philosophy.

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* Source and arrangement of procuring of steel, plants &equipment, etc.

* Type of plant & equipment proposed to be used.

* Names of firms with which association is sought for toexecute the work in the Contract.

* BOQ of major equipment

* Technical leaflets and general constructional details.

* Type test report of similar equipment.

* Implementation schedule.

* Auxiliary power supply arrangement.

Bidder to submit the Performance certificate for major itemssupplied /manufactured by them like CT, CB, CVT, PT,Isolator, Relay & protection Panel for satisfactory operationof at least three years as on date of bid opening and shallensure that offered major items shall be supplied by them onlyfrom same manufacturing unit /works against which they willsubmit the above performance certificate.

5.2.0 After the Effective Date of Contract, the Drawings shall besubmitted after the date of contract progressively and thedocuments will generally be as follows:

* Schedule for project management.

* Complete Bill of Materials.

* Single line diagram giving rating of each equipment.

* Design calculations in support of selection of equipmentrating and system design.

* Layout of switchyard with sections.

* Technical particulars of each equipment and accessories.

* Grounding & lightning protection drawings and details.

* Cabling, cable trench, tray layout and culverts with section &details.

* Dimensional general arrangement drawing along with cross-sections for equipment.

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* Quality Assurance Plan of major Equipment

* Test Certificates of major Equipment Foundation plan andloading data.

* Design calculation and detailed drawings for Civil work

related to this specification.

* Design calculation, GA drawing for Switchyard structureincluding equipment supporting structure and subsequentlydetailed drawings.

* Mounting details of equipment and structure.

* Control schematic and wiring diagram.

* Cable schedule and interconnection scheme.

* Relay co-ordination.

* Pre- Commissioning & commissioning checklist.

* Civil and Structural analysis, design calculations and workingdrawings including bar bending schedule and fabrication.

* Erection and maintenance manual.

* Any other drawings & data as required for satisfactory installation,operation & maintenance.

The drawings, data and manuals listed above are minimumrequirement only. The bidder shall ensure that all other necessarywrite-ups, curves and information required to fully describe theequipment & system offered are submitted with his bid.

6.0 FEATURES OF TESTING & MEASURING EQUIPMENTS

The following test kits shall be compulsorily included as part of thesupply of GIS for testing & maintenance purpose.

6.1.0 Numerical Universal Relay Test Kit

The test kit shall be complete three-phase test system consisting of thefollowing:

a) Base Unit (i.e. input Power and Control module)

b) Timer, Monitor and Battery Simulator module

c) Voltage Amplifier module

d) Current Amplifier module

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e) High Current interface module

f) All types of leads & cables, field enclosure and accessories.

The test kit shall have following minimum features:

* Modular design for system customization

* Steady state and dynamic testing capability, including DC offset

* Capable of GPS satellite synchronized testing

* Totally automated testing

* Capable of performing Transient tests via DFR replay and EMTP /ATP simulation

* Capable of performing end-to-end tests

* Continuous LED displays

* Immediate error indication

* Automatic range changing

* Manual and Computerized control

* Wide-frequency bandwidth

* Built-in RS 232 interface to perform computerized testing

i) Features of Input Power and Control Module

* Auto-selectable input voltage from 95 to 265V AC

* Communication and control ports for Clock-In/ClockOut and Synch-In/ Synch-Out

* A 32 Key Manual Control Keypad havingfunctions like SYNC/PR, SYNC/SZ, SYNC/IM, A-

OFF, H-WAVE, LINE SYNCHRONIZATION, HORN,etc.

* RS 232 Interface Port

* Optional Expansion Slot

* Sealed Membrane Switches

ii) Features of Timer, Monitor and Battery Simulator Module

* Times High Speed Relays

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* Multiple Continuity Monitors

* High resolution (00.005 to 99,999.9 Hz) andaccuracy 0.002% of reading

* Continuity light and audible tone generator

* Programmable de-bounce for eliminating falsetriggering and contact bounce errors

* Programmable contacts to simulate A/Bcontacts of a breaker for automatic testing ofbreaker failure relays

* Adjustable voltage thresholds

* Battery Simulator (with a max of 10% rippleand 20% accuracy) to eliminate the need foradditional dc voltage source

* 6-digit, high intensity LED display

g) Features of Voltage Amplifier Module

* Tests high instantaneous and direct contactedover voltage relays

* Test potential to 600V rms

* High resolution (00.001 to 99.999 Hz) andaccuracy ( 0.0006 %)

* User-defined waveforms

* DC to 20 kHz bandwidth

* Dedicated Display for waveforms such asoutput voltage, phase angle, frequency etc.

* Dedicated RAM storage for waveforms and/ortransient waveform events.

h) Features of Current Amplifier Module

* Plug-in design to add or reconfigure test systemto meet changing test requirements

* High resolution and accuracy

* Parallel operation up to 90 Amp

* DC to 20 kHz bandwidth

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* Less than 0.2% total harmonic distortion* Dedicated Display for waveforms such as output

voltage, phase angle, frequency etc.

* Dedicated RAM storage for waveforms and/or

transient waveform events

i) Features of High Current interface module

* Plug-in design

* High resolution and accuracy

* Provides high current, high power testing

* Less than 1% total harmonic distortion

* Dedicated Display for waveforms such asoutput voltage, phase angle, frequency etc.

* Dedicated RAM storage for waveforms and/ortransient waveform events.

6.2.0 Primary Current Injection Test Kit


* Tests relay protection systems and their current transformerstogether

* Two levels of current, and voltage outputs and auxiliaryvoltage outputs on both units

* Hand-held, hard wired remote controller

* Continuous operation at 40% of maximum current

* LCD readout

* Controlled switching for preventing spontaneous restart ofoutput after power interruption

* A built in timer with forward, run back and dual modes of operation

* Maximum current Output AC: 2500A at 0 to 3V, 50 Hz and1000A at 0 to 6V, 50 Hz

* Auxiliary Voltage Output AC: 0 to 250V, 2A, 50 Hz

* Current Range : 0 - 2500A, resolution 1A

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resolution 0.01 A

* Accuracy : 3% of reading, 2 digits

* Duty Cycle : 2.5 minutes on and 15 minutes off at full rangevoltage and current.

* Equipment Protection : Circuit Breakers 30A rating

The test kit shall be complete with all types of leads & cables, fieldenclosure and accessories.

6.3.0 Universal Circuit Breaker Test Kit


* Automated Testing

* Rugged Instrumentation and control

* Direct connection of draw-out type breakers

* Integral clock/calendar

* Zero DC offset

* Easy to read display

* Output Stabs sets to provide quick connection to breakerunder test and to connect to virtually all Multi- Amp Circuitbreaker test sets

* RS 232 interfacing for printer options

* Digital Memory Ammeter (Range 2500A with 3 digit display)

* Digital Timer (Range 0.001 to 9999s, with 4-digit display)

* Timer Leads

* Input Leads* Stub Series Bar

* Logic and metering cable interconnect

* Input auto-transformer with interconnect and jumper leads

* Input Voltage 460V 5%, 50 Hz.


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* Capable of performing periodic maintenance testing on circuitbreakers, and start up tests on new or repaired equipment.

* Hardware Characteristics:

i) Optically isolated digital input channels for main orresistive contacts

ii) 2 current analog inputs, each measuring Close orOpen coil currents

iii) 1 close coil command output

iv) 1 open coil command output

v) Total Recording time from 1 millisecond to 17 minutes

vi) 12 bits analog resolution

* 1 high speed communication module fiber optic

* Complete set of cables, manuals, power cord

* Displacement Kit, Extension cables, Extra I/O cables


6.5.0 Numerical Contact Resistance Measurement Kit

The test kit shall have following minimum features:* Employs Four Terminal DC method

* Seven range selection by means of push button

* Temperature Compensation

* Automatic zeroing

* Measurement Range: 1 Ohm to 1900 Ohms in seven steps

* 4 digit display (1.9999 Full Scale)

* Accuracy: 0.05% of readings 2 digits


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7.0 CODES AND STANDARDS

7.1.0 The entire scope of work shall be carried out in accordance withestablished engineering practice and in conformity to this specificationand with the relevant specifications and codes of practice of the Indianstandards.

7.1.1 All equipment and materials shall be designed, manufactured andtested in accordance with the latest applicable Indian Standards (IS)and IEC except where modified and/or supplemented by thisspecification. In addition, work shall also conform to the requirementsof the following:

a) IS : 10118-1982 : Code of Practice for Selection, Installationand Maintenance of Switchgear and Control gear Part-3(Installation).

b) Central Board Irrigation & Power (CBIP, New DelhiIndia)Technical Manual on Layout of Switchyard, Report No. 3

c) Indian Electricity Act and rules framed there under

d) Fire insurance regulations

e) Any other regulations laid down by Central/State/Localauthorities during the execution of this Contract.

7.2.0 Performance, Standards and Codes for GISPerformance, testing and rating of the switchgear shall conform withthe latest edition of the following IEC publications:

IEC 60694 : Common clause for HV switchgear and controlgear

IEC 60517 : Gas - Insulated metal enclosed switchgear forrated voltage of 72.5 kV and above.

IEC 62271 : A.C. High Voltage alternating current circuitbreakers

IEC 60129 : A.C. disconnectors and earthing switches

IEC 60185 : Current transformers

IEC 60044 : Current and Voltage transformers

IEC 60099 : 4 Metal - Oxide Surge arresters without gaps forA.C.system

IEC 60137 : Bushings for alternating voltages above1000V

IEC 60376/61634

: SF6 gas/ Use and handling of SF6

IEC 61128 : A.C. disconnecters, bus transfer, current switching

by disconnectors

220 kv gis

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