(i:;}l-,..i

, , '

- ,'" :~~,~30~2006' 638 (41)~

"

CHAPTER:;a :

TRANSMISSION METERING CODE'. "

8.1 Qeneral Prl"clples

8.1.1 The scope of this part, of' the' grid code covers' the practices th~t shali be'employed and the facilities that shall be pro,vided'for the' measurement and,'recordi~g ,of~ariou's'parameters of electricity,tra~smission' like active/reactive/~pparent power/energy, power factor;voltage,frequency etc.,

,

, ,, '

'8.1.2 ' This Code sets out or 'refers' to the requirements of metering at generating,, , ,- stations, 'sub-stations and interfaces for' check meter, consumer meter' "

(tariff meter), ,correct meter and ,energy:accounting 'and audit.,meter, interfacemeter and main, meter' as s'paclfied In the CEA (Instailationand Operation of

. Meter) Regulations, 20,06. ' ,','. ' "

"

..

, ..,

, : 8,1.3', Thi~ Coc(e',also specifies' the' r~quirement,,for calibration/:testing' and.commiss!onlng of, ,meterlngequlpments \liz.,energy meters with associated'

, accessories, current transformers 'snd voltage transformers. The' code broadly''Indicates the technical features, of variou$,:'elements"of 'the mete~ng, data' , "'communication, testing and ,calibrationsystem, the prQcedure:for,assessment of

. consumption In 'case of d~fectlve a,nd' stuck~up,meters and also lays down

'., guidelines for, resolu~ion of disput~~ ,be~een, d~fferent agencies., " ' '

8.1.4' 'The' generating plants supplying:powerto'the, ~pen actess consumer, WIII"b~' 'requiredJodo the metering as per ABTscheme',and ABTmete'rswill,be Installed

, both::eJ1ds Le. injection po!nt and drawalp,oint :,' " ," ,

"

, , . , "" "..'

8.1.6 Open access customers/consumers sl\allhaveto, provlde'software for billing to" , " licensee aDdfor operation to SLOCwithcomi1:tunicationfaciHtyfor transfer of r~al,

timedata throughv-setort~~oughlease ~ine."" " " '

,..-n 'l "Reference .Stand~rci8 , ., ,, ,

8.2.1, The following'Indian,Standards (as, amended to date) shalt be applicable asrelev~nt to meter~ and associ.ated eqljipment:,;,,' ' " ' ' ,

.'

S.No. Standard Standard Title' , , , , '

Number, .' ,"

IS 13779 AC Static Watt-hour MetersforClass tand 2I IS 14697 AC Static Transformer Operated Watt~hourand VAr-hour '

. . Meters, , ."

, Clas's 0.2S and 0.5S ' ,

,IS 2705' IndianStandard forCurrentTransformersIS 3156 IndianStandard forVoltageTransformers'IS 9348 Indian Standard, for Coupling,Capacitors and Capacitor

Divider, " . '

!S 5547 IndianStandard forCapacitorVoltage Transformer'I. CBIP' SpecificationforAC Static ElectricalEnergy Meters

, Techl1lcalReport - 88 .

. ,II. ':BIP, Specification.f~'r.CommonMeterReading InstrumentTechnical ' , 'Report - 111

.--

."

:638 (42)

, ..,

Amrcr;r, ~ 30 ~ 2006',, ...

8.2.2 The fo.llowing hite~national Standards (a$amerid~dto date)can be applicableasrelevant to met~rs and associated. equipment not complying to Indian Startdards

.or not manufactured!n India:. ' ' .' . ."

;1f.

., I St,andard Title

..

~~

8.4' Facility to be Pr()vld~d,o.n Meterlrig'Locatlons. . "'" .'." ,The user(s) shall make available the required space and th.e required outputs of the''. , specified' curreritandvoltage tra,nsformers to facilitate Installation of meters 'and'

associated' equipment.. aAd. shall, calry', out operation and maintenance. of these' ,equipments. Nec~ssaryauxiliarysupplY'shali be extended,up to the metering system, ifmeterispoweredbyonlyexternalsupply. . '." . . .' "

. ., . .

Appnca~lon of me~erlng .sys~em I'.' '.' .

8.5,.1' .Generating plants and Ope,11Ac(:eSsCu~tome~: .' ';".. .For, existing all non. conventional' sources biased - Generat.ing plants(NCE). .

, Generating plants and Open Access Customer shall'pu.rchase and provide ABT.metering system and software within'two month from-the' issue of this Cqde, in'

, absence of ABT meter permlssionf~r o'pen"access shall we withdrawn, It is also', compulsoryfor Open Access Customerthose who a're receiving power from'

NCE. ". .'

8.6'

, ...,.., .'''''' .

..

.

----

. In case of generatir",)plants/OpenAccess' Customer availing/seeking openaccess, the metering equipments shall be Ins{alledpo incoming/outgoingfeedersof grid substationfrom the power to be injectedor draw.".:

. .' , ,In case of. any distribution licensee 'availing/seeking open' access, meteringequipment shall be installed at each' supply points interfacing with transmission

. network. ' . .' .,'. .'.':.. '

8.5,2 The check meters shall be installed on each gen~rator terminal, HV side' ofgenerator step-up transformer (GST),' LVside of unit auxiliary transformer (UAT), ,

HV side of Station Transformers' (ST) and all outgoing feeders at generating .

. piants to work out energy generated and energy delivered by the power station In',the grid. Commercial sett!ementshall bebased on the energym,eter$lnstalledat

inte,rfacepoints as defined in this code or applicable PPA, .

, III. IS 9000 Basic EnvironmentalTesting Procedures for Electronic ..&. glectricafltems . ' .'

Iv .IS 12063 IndianStandard forclassificationof decrees of orotectlon

. S. No. I StndardNumber

i. . IEC 681"..

ii. . IEC 1036

.m .' lEG 1268

I'"", -..,.

of

,... ... c-' . ,.. ..' .

.... <,,' .,' .. '

A ~,~30.~2006' ,:

. .

"

",. ""

"EO638. (43)

, 8.5.3 'Me~er'lng betwe~n State ~ranSrTlIs.slonutility-distribution I~censee:, " ~ ", ' . . , "

,(a}... For measurenient ot' power"deiive,redby State lransmission utilityto, . distribution liqensee (excluding station ttansformer consumption), metering shall

'.- ,be providedon the LVside o(EHV Power Tr~nsformEirLe. 33kVside of 132/. : 33kV and 1'1kV side of 132/11kV transform,ers installed in EHV sub-sta~ions..

pp:erc;ttionalmeters sh~1Ialso be' provided on 'aUoutgoing 33kV and ,11kVfeeders for-energyaudit on.feeder and reconciliationof energy withrespect to

, energy nieasuredon L'( side of EHVpowertransformer. "

(b) In case ofEHV industrial and railway traction:cQnsumers of.distribution,, " licensee directlyf~d from 220kVor 132kVsub-station of State transmission

utility,tariffmeteringshallbe'providedon outgoingfeeder emanatingfromEHVsub.,station of St~te tral')smissibnutility. ' ' ,

f

., 8.5.4 Sub-station Auxlllaryqonsumption Metering:' ,

, " . ., ,

,,'The St~tetransmission utilitysub~stations ~uxiliaryconsumption shall be recorded on ,

LVside of station au~iliarytransformers. Ifsuch transformer(s) i$ feeding other localload (colonyqua'rters,street lightsetc.) apart fromsub-station auxiliaryload, separatemetering shall be ,providedon ~ndividualfeeders: ~,"

. .' . . ' "

Exceptuni9irectional kWh, other data logging/billingcapabilitiesfenergy registers/other. featur~s m'aynot be requiredfor this application. .". ' '

8:5.5 ' Operational Metering: .' "

.Oper:ational,metering shall be site" wherever reasonably required by,State".tr~nsmission utility/generating c.ompaniesfor,applicationsother ,than tariffmetering." .The 'parameter~ and other requirementsshall~e finalizedbyState transmis5.ionutility

, based on 'the ,operatio~al requ~rements.' .' , "" . '

8.6 Ope.ratlon and Malnte.nanCe,of ,the,Metering'Syst~ml. ,',:" ,.,.,.,' ,:',.. '

" ,The maintenance of the meters shail be the exclusive, responsibility of the owner/licensee of. the meter~;'The operation and iTlaintenance,Of'themetering ~ystem in~lude'sproper'

installatiQn,regular maintenance of the mete~ingsystem, ,chec;:kingof,errors of the CTs,VTs ,and rn.eters, prope'r layJngof cables and protection:thereof, ch~'aningof connections/jo'ints,'..checking ot..voltagedrop in t~e CT/VTleads, conditionof meter box and enclosure, ,conditionof seals, regular/dailyreading.meters and regula~qata r~trievedthr04gh common meteriQ9,..,

. "reading instrument(CMRI)and data processing:system(QPS}, attendingany breakdownffaulton the. metering ,system 'etc~ ", ' .

---

..

, 8.7, ,

Minimum.techni~al requirements for ene~gY,plT1~ter

. 8.7.1 Me~suringEI(3ments:The meter shal! be 3 phase 4 wire,fullfour quadrant type staticTri-vectorM~ter(TVM),whichcan be used for 3 phase 3 wiresystem or ~phase2 wiresystem (traction application) without affecting the metering accuracy and.ot,her

, essential parameter~... "

8.7.2 MetershallbasicallyIncase ofimportand exportpowerrequirementofdifferent .degreeby the captive powergeneratorsl (!onsumersthroughthe same connectivity/line,itwillbe ensured that the.ratiobetween the two I.e.lmpprt/exportor export/importshould bewithln'ratio1:20. '

8.7.3 , In case where import/exportor export/importratiolies within1,:20,the meteringwillbearranged through meters and CTs having class 0.5S accuracy class and metering'core. of CTs with 5 Amp secondary rating. The minimumlimitof import and exportwould,be, 1MWon either side Le. Importor export side.

,

638 (44) .. '1'\ ~;~30~2006

. . .. , . '

8.7.4 ' The,AST meter shall h~ve facility to correct, the ratio error and phase angle error,, of external CTs and VTs connected to it. ' "

,,' " " ,

8.7.5 To measure fundamental rms value ofe.lectricity and harmonics.. " " , .

'.8.7.6 Operating System Parameters (for balanced and ~nbalanced load): '

, '(a) Operating Voltage Range: The. meter' shall work satisfactorily, on 110Volts AC (Line-Line) or415 Volts AC (Line-Lilie) with variation, rangeof -'30% to + 15%. , ' " ',.' ' "

, " ,', ' ': ' ~", , '." " "

,(b) , ' 'Op'erating Frequency Range:, The meter shall work satisfactorily on '

, 50:Hertz with vari~tion ran~eof -5% ,to ~5%..' , .(c) ,'Operating Power Factor. Range: The meter shall work satisfactorily over a

power factor range of zero lag to unity to zero lead. ', ,

8.7.7 Rated Nominal Curr,e'ntand Rated Maximum Current: Meter shall operate on'lAmpere' Qr ,5 Ampere from CTsecondary 'circuit. Rated maximum secondary ,

, cu'rrent shall not exceed 120% of nominal current.. ;., .

8.7.~.,' Rated Short 'time: Curre~t: Meter shall be capable ofwith~ta~ding 2'0 times tlie', , rated nominal current for 0~5 second. ',' " ' " '

8.7.9 . Minimum St~rting Current The meter:shall' $tart operating' arid recordin'g energywith mi'1imum .sta.rting, current equal to O.t % of nominal current at 'unity power

" factor.'. " , , ,.. ,: , . ' :, ,, , ,

, 8.7.10 Burden and Power Consum'ption: The burdeli imposed"1>ythe metering systemshall ,not exceed 1 W, 8 VA for voltage, circuit and 1 VA for current. circuit so that

, there is no 'significant voltage drop in the VT and CT leads., " .. ..' ,, , '. ,. ,

8.7.11. Accuracy Cla's8 (Better: tha'n the mentioned a~c!Jr~cy class shall be acceptable):, ", '. " " ' '''-, ' :' "

" . ,.- ".'..'''.

8.7.12 Earthing System: The' metering,system shall 'be suit~ble ,for solidly earthe~power system.' "

, .

8.7.13 Meter Box: The meter box shall confirm to the degree of protection not lessthan IP-51'as stipulated in IS 12063, and shall be capable of satisfactoryoperation in an in'door,non-air conditioned installation. '

8.7.14 Installationah~ mounting:

, The meter shall be suitabJefor' install indoor or outdoor application: The' meter. can be mounted in dust proof, lockable and tampe.rproof panel or ,rack or metal

box, as per requirement and site c°'1dition, conforming to'm,inimum IP-31 ,standereds. '

Particular ' Parameter ,: Main Meter Check Meter Sub.stalon, .. Auxiliary.. - ' '

Meter.'

,

I. Tariff Meter' . Active Energy 0.2S ,O.2S , 1.0

Reatie Energy .' 0.58 .p.5S ' 2.0" .,

Operational Meter Active Energy . , 0.5/1.0 0.5/1.0 -II. Reactive Energy .' 1.0/2.0 '1.0/2.0 '- . '

..

--

~,

.-'.,

, ",. '.'" ",,-, ."",-,.

"

" ,

, '., '," .~. ..

. " ',' ".. ,,

','\,\ I

" ", "" "'11',

. " 'U~~'I~~,~30~~' """ ,638(45).

The meteringsystemsh~1Ihavefacility GfCTsh~rtlng' when .'themet~~odule iswithdrawnor dismantled. . . . ' , '

"

, ,, '

B.7.15, Data Dlspl~y Capabilities '..lnstantaneousVelues: ,,"', , ,, The meter shall be capable to record and display(on,demana) at le~st..thefollowing'

,Instantaneous parameterslinformatlon,: . ' " .' ',,", -, ,. ' ,

(a) , Three rms IIne'voltages '.. "

,(b) Three' rms line,currents, " , , .

(c) 'Syst~m 'frequency (I-:fz) " " "

(d): P?werfactor with'sign of lag/lead;, '

, (e) Watt-Import, ' '

(f), '" Watt ~Export

,(g) VAr-Lead, '

.(h) VAr-Lag', '

(I):,' VA-Import', ,

0) "~A~ Export ,'-, , ' ' " ",'

(k)' Ma)(lmurpDe.man~'(ltnport)durlng.the monthIn Watt and VA'withdate and

time, "" '." ' ,,', ",' ',' ," ,', .,' "..

Maxl":"um De,m~md (Export) durlng,the month In Watt and vA with date and'~Ime,' ',,"""',, , '

(m) , Meter Serial Number:

" " '

~

,.,

t

." ,(I)

:--', ', , "

, 8.7.16, Data 'Storage Capabilities,,: Cumli19tlveValues: ,, ' . ~" ,,' "..", " ,

, The meter shall be'cap'able to record. store 'anddisplay(ondem;and)'at least followingcumulative.parameters. Atleast five(5)'registers shallbe providedforeach parameter. '

, out of whichone '(1) register shall record energyfor 24 hou~s.lna day V'hereasotherfour (4) registers shall recor~ Time of Day.(TOD)'energy during morning peak.morning offpeak. evening peak and 8veni,ng off-peak durations: " , '

, (a) , :Watthour-Impo~(b) Watt hour --Export ,

(c) VArhour - LeadwhileWatt hour '- Import

(d) VAthour ~LagwhileWatt hour -""port, '

(e) VArhour -Lead whileWatt hour -Export

'(t)' VArhour -LagwhileWatt hour -Export. '

(g) VAhour-~mport .

{h} VAhour -Export

(I) ,VAr hour duringlowvoltage'(V<97%)*

0)' VArhour duringhighvoltage (V>103%)* ,

.These parameters are for Availability.Based .Tariff(ABT) purpose only hence TODregisters are no~ required ' ' ,

~

"

, '

638 (46) C\ ~,~30~2006 " ,",',

.8. 7 ..17' Data Logging Capabilities 1 - IntegratedValues:

,"

, ' ,

The meter shall have sufficientmemory,to store any combinationof at least ten (10~parameters listed in Clause 0 and Clause 0 over mi,Jiimumforty(40) days at a logginginterval'of,fifteen (15) minutes. The State transmission utilityshaHbe able to selectthe~e parameters locallythrough optical port using CMRI'and/or remotely throughcommunication port, At least, following'essential parameters shall be logged at anintervalof 15 minutes: ' ,

"

(a) Watt -Impbrt

(b)' ,Watt- E~po~ ,:(c) VAr- LeadwhileWatt- Import'

,(d) VAr -Lag while'Watt~ Import

(e) VAr.-LeadwhileWatt- Export, ' " ; , . .(f) , VAr~ Lag~hlle Wat~- Export ,

(g) ,VAr ,hourd~ring,lowvoltage (V<97%)

(h), VArhour dur~nghighvoltage,'(V>103%)(i) Average.frequency (Hz), '" "

m' Averag~ thre~ phase 'voltage,' :. " , '

" In case of operational metering, thenJmber of parameters and their Jogging int~rvals, '. shall be decided by the Lic~riseeas per their operationalrequirements~ '

, ',8.7,.18 Oth~r Parameters: - , ,,'., "'", ','

, Each meter shall 'also store the 'values of.active energy (Import), active E!nergy(Export), reactive"energy' (lag) and reactive' energy (lead) 'separately during active',

,. ~nergy (Import) & active energy (expart) cond.iti()nsrecorded at ,24.00 hours on last, day','of the month fqr' a ,period of at.leasttwelve (12) months; user shall be able toprogram'time anq day at 'Nhich'..y.alu,e,of energy to be,stored in the memory.

,

,-, 8.7.19 Events and AhnormalltiesLogging;papabilities: , '

ThemetershaU be' able to, h~~{d~J~,anciJime sta'mped events captured with,aresolutionof at least one ,(1)second. ,Sufficientmemoryshall,be providedto store"at .leasUast 100 events in the~meteron Frrst-ln~First-Out(FIFO)basis with compartment

, wisea$following, b~t ~ot limited to:. :''''''' ' , "

(a) Missing,potential.(vt supply missing}'(b) CTNT Polarity' reversal ' " , ' , " ,

(c) "., Current unbalances (magnitude: as well as phase unbalance) in anyone of the, phases or 'morethan ol)e phase ' '

Voltageuribalances (magnitudeas wellas phase unbalance) in anyone of thephases or morethan one phase, \ '

Supply interruptionsalong withthe durationof each interruptionTamperinformation/anomaly'occurrence/anomalyrestoration, '

Meter internalset-up/program change information

(d)

(e)(f)(g)

8.7,20 ~eal Time Ci?ck (RTC)and Calonqer:The meter shall have in-builtQuartzcrystalbased accurate,RealTime r)'.Gk. Themetershalldisplayre~1time1n24 hoursformat(hh,:mm:ss). .Meter shall also di~playthe date as per Indiancalendar in,dd-i!1m-yyyyformat.Thirty(30) years calendar with automatic leap year adjustment shall be provided in the meter,

The accur~cl O;t.hd deck 2n'd caI8\1d~rshall be better than one ~ninutep(~ryear.

-~-~

~{?i,¥j

A ~ ' \ ~'

~,I"'~I'" 30,~2006, ' '638 (47) ~ ,

8.7.21,, f -"j

," '1

Time syric,hrOriization: " , ",' , ", ' , '

Allmeters' shall have facilityfortime ~ynQh~n1satiorilocal(yand/orremotely througha '

Global Positioning System (GPS) or through the 'centraLcompute(at CDCC) using ~,the 'same port us'ed for remote data communicati~n.' , '

8.7.22 Data.~e~entlon:' " "', ' . .

The logged data shall be stored in a non-votatilememory of meterwith a niinil:num'

r,etention' period <?f ten (10) years without any battery back-up,' , , , ' ," '

8.7,23 Data con~entratlon andnetwork IntegratIOn:" " "

The local network of all ,meters installed in a sub-station shall be formed using mOdeml '

, multiplexef/dataconcentrator/l:ANhub switch. This local networkshall be integratedwith communicationnetworkusing a'ppropriat~stan~~d protocol. '

r

, ' , , '. .. " '

" " Com,municationnetworkmay~e based QnRadiofrequency,Microwave,PublicSwitchedTelephone Network(PSTN),Power LineCarrier Communication(PLCC),VarySmall

, Aperture Terminal(VSAT)network, Optical Fibre Cable (OFC), GSM, Radio or any", 'other means,oftelemetrY, ' , ,'..';' ", " I , ,', t ",' "

"

-~

. ,, "

.. "

, ..

, 8.7,2~ PUlseOut~u't':' ", " ,:,',""" ' , ",

High,intensity lightemitting,~iodes (LEO)shallbe providedon front'of tne meter fpr '

, ,test calibration' and accuracy check of ,Wh and VArh mea'surements. '

8.7.251;1}splay: - . ".',(: ". . .: Meter shall have a m.inir:nu,m',of7digits,Alpha:-riumericliquidcrystal display (LCD)or

lightemittingdiode (LED)type.displaywithbrightback-light'and automatic back-light, timeout.feature.A~ouchkeypador pushbuttonsshallb~provided,onthe meterfrontfor'switchingON the display and for c~an9ingfroin one indicatiohtonext. Two'separate,push buttonsshallbe providedone forscrollingand otherfor MDresetting.' ,

, " ' " ' .", "", " , ',,' , ,

, ----

'8.7.26 DataSecur,lty:" ,''','

, (a)', pata encryption '(coding) ~apabiii~,',:','" . ' "; ,(b) , Mechanical seals and locks i:e. seallngp,rovision forterminarblock, meter cover, '

" MDreset predefined date and timeor9MRI and all communicationports,; ", "", , . ' "

Message authenti9ation~Igorithm'Cap~bi\ity/Multi~le\tel'passwqrd protection'," . ' " ' ,.' " " , "

,Independent security across commvriicat!pn' chann~ls

" : "(c), "

, (d)

8.7,27 ~elf-~iagnostics feature:' , , " '" ' ,

" The meter shall have self diagnostics feature to scan the healthiness of I ~!ernalcomponents and circuitry,On'defection'of any exception or fault, meter shall 'c:isplaythe message immediately.

8.7.28 Communication Ports:

T~e meter shall have at least followingcommu~icationports:

" (a)' One 'optically isolated infra-red communication port '(optical port) fC\r localcommunicationas per IEC1107 '

, ', ' ,

(b) One galvanicallyisolated Ethernet (LAN)port or RS485 serial port or' ~;i2~2. serial'port.forremote 'communication

"

.--

'.

, 638 (48). " ,

'.d'~"'"'~;~30~2006 '

8.7.29, Communication Protocol: ",

',', :' , ' , " " '.

For communication by meter ~ith external :devlces, me,ter supplier shali implementindustry,stan9ard'open protocol(s) Ii~e,MODBUS RTU, MODBUS, TCP/IP, IEC 870- , -5-102,IEEE1317,DNP 3.0, Device Language Message Specification (DLMS) or anyother industry standard protocol. ' ,", ' ' , ,

, ,, ,.' , ' , ,

,In case, of proprietary protocol" the mete'r ,supplier shall furnish the proto~ol softwareand details of proto~ol followed by him. Any variation'hi the standard protocol foroptimizingcommunicationresources:shallbe detailed.' ' '

8.7.30,Repr.ogra.mmlng,of the ,meter:, , ' " ' .' ,

Utility shall be able 'to select tDe' display para~eters, logging parameters, timings ofTOD regisjers, bililngdat~si logging interval or alJyother para,meter locally using CMRIthrough bptlcaland/or' rem9tely using meter reprogramming software Installed 'at CDCCthrough communication port(s). " '

8.7.31 Data'Downioadlng:, ," ' .. " "l ' " .', ..

Utility 'shall be ablete download the logged data locally using CMRr through optical,' ,," port and/or remotely using meter Interrogation sQftware.lnstaliedaf CDCC through

communication pQit(s). Any interrogation/read operatiol1,shall not delete or alter aoystored meter data.' ' " , ';, ' ", '

" ,""""'~ ~;~ ' ,

'8.7.32 External auxiliary supp'y:' ,',';'-:- ',' -- " . ' ,, ' : " :' "', """'7"-""":Ji::' , " ,

The ry1eteringsYs.temsh~l! derive: Qper~tintC.~Y$.ij:.mfrom AC,or Dqauxili~ry supply.and shalJ not load, measurement PT's fot 1lie,lLQPeration. The metering, system shall

, automatically switch between 'the ACIDC 'auxilia'iV supplies' bas~d on its availability.The:standardauxlliary YQltageshall,~~ 11'OV~-or~OVAC and 11QV or.240V'oC.Thevoltage regulationhi'the auxiliarysupply shall bei.within it... 10%.' , ,

, ,,- .' " ',' ' , '.":";.~:.~~~: -' '

'-.-'~,' ,"- ",-'

, ~l' "

,r

'1: ""

, "

I'" ' " , ' , -

.8.8 '" ,)~Inlmum technical requlrementfor.lnstrul11elit~!!.~W!~nsform~r:, '

'8.8,'1, Single-phase type cUfrenttransformers' sha1[fu~ed for :3-pfia~-~';rwfre"~rtdIph~';~"""- 3 wire'or 2 'phase 2 wire system (traction:,2PpJjQation)measurem~nt: sy~tem::',rhe-,second"ary'curre!"t rating' of the' current triiiisfOriher("C!)~,shall.be~-1...arnpere';or'5'~;

ampere depending upon the total circuit burden.,§A secondary can be used for low,burden circuits. ' " ," ,-~,~,-i£;":',, , - " '

,,,'---'--

..-. ... ,-~~

-. 8.8,.2 Either ~edicated set of CTNT or dedicated cor.eof current transformers shall beprovidedfor metering and wherever feasible, CTs(or their cores) feeding to main metersand check meters shall be.separate. The,eriors..otthe CTNT shall be checked in the,laboratoryor at site. The errorsof the CTIVTs.slialfbe tested using National accredited'mobile Laboratory (NABL) or at any accredited laboratory and recalibrated if require~at manufacturer'swqrks. ' ' ,,' , " '

, ,

8.8.3' The total burden connected to each current transformer,shall n~t exceed the rated. burden of CTIVT. Total circuit burden shall be kept close to rated burden of CT forminimum error and percentage voltage drop in VTleads shall be within thepermissible limits. '

8.8.4 Either Electromagnetic Voltage Transformers, (EVT) or Capacitive Voltage transformer'(CVT) may be used for metering purpose. Generally, voltage tran<;form~rs(VT) is used

-,to cover either EVT orCVT. The secondary voltage per phases: ",abe 110/v3 volts or415/v3 volts. Fuses of proper rating shall be provided at appropriate locations in theVTci~~ ' , ' ~,

-. ,\:. ',.j

.\!. !~

'.-

'1

~

I

;(6'(~')"'-"""¥'...,,,' "

, '

i:I ~,~'30~2006 638 (49) ,

8.8.5, - ' ,

The minimum acceptable detailed specificati"onfor instrumentation transformer areasfollows. ' ',,' , " "

, ,

,A) Minimum acceptable'speciflcatlonsof dedicated single-phase EHV&HVcl.lr.rent transformers (CT) for metering, ' '

J

J'"""-.--

..----

.-- ---

S. Particulars' 11KV 33KV 132KV 220KV' ;,No.1 Nominal System 11 33 " 132 '220 ..

Vol'age,(Kv'rms),2 'Highest System 12 36 145 245 '

Voltaae (kV rms)", ,

3 Reference IS 2705 with lates amendmentsStandard' , "

""

4 Standard CT Ratio OOO-1000/1-1. 800-400/1,-1 , 800-400/1,: 1-1 1200-600/1-1-1-,

1. ':" .

16,99-800/1-1 '600-300/1-1 400200/1 1-1 800-400/1-1-1-1,, .

1200.,600/1-1 400:,200/1-1, 200-100/1-11 ", ,

', :','

" ..

800-400/1 1 300-150/t..1-/, 100-50/1-1-1,, " , '.

. , "", ", ' ,

600-300/1-1, 100,;50/1-1:,..

400-200/1-1, , ' ,

300':'150/1-1'. ,

150-75/1-1 ' , " ' -6. No. of Metering' Two ..

cores.. . ,

,6. Rated Continuous 10% o Rated,rimaryCurrent

Thermal' Current' " '.. ' , ,

,7, Rated' ShQrt ,time 13.1 KA,.for 26.2, KA fQr "40, KA for' 1 40 KAfor 1 secthermal, primary 1 sec 2sec '" ':sec "

current"

.,' C'.."

8.: CT characteristics' :' "

(a) . Rated Primary 2000-1000 8PO-400'"

,400'

'800Current (Amps),

",

,,1600-800, 600:'300 :'.200

, 1200-600 " 400-200"" '100 ,800-400 . 300150-' .:, ,,50 "

.600-3.00 100-50 ' 'w

, ' 400-200 .., "

300-150" " : '.. ,.-

,150-75 -(b) Rated Secondary 1 or 5' 1 or 5 1 or 5 1 or 5

Current (Amps). '

(c) Accuracv Class 0,2 0.2 0.2 _9.2.-

"-(d) MFiximum 5 5 5 5

Instrument ..

Security Factor,w

<lSF)(e) Rated t, condary 30 30 ' 30 40

Burden l\i).. .

9. Refere!',::: IS 335 With latest amendmentsStandsl,' forinsulathr il ;

.. _.... ----,_._-

. .638 (5,0)

~~~.i~~, ~ 30 ~ 2006, '

B) " MlnlfT!u~' aCCQ'ptable specifications of, dedicated three.pha$eHV CT.PT set, formetering'

"

.

C) .. Mln,iinurTt acceptable specl,flcatlonsof. dedicated $1~91e-pha~e EHVcapacltor ,

voltage transformf!rs:,(cvtUor metering'

'13~kV ',,' 220kV132 ' 22.0

. 145 245IS 3156with latest ~mendments '

4400 of with tolerance +10% and -5%

Shall npt exceed 200 pFShall not exceed 20 micro siemens

Within 80% to 150% of rated capacitancf; ,, ,

, '---J

!" I

I\, .

, ,- ---

'."

, I

, --, ''''

..

.--...

. ' ,

i

1

'

,

'Y'1', .;~ m.,-,' ~, ;i I

.t:"

,.-S:No. Particulars " \ 33kV

Specification of CT (for CT"PT Set) , ,

, '1 NominalSystem Voltage (kVrms) , 33,2 .HighestSystemVoltage(kVrms) , 36 .,3 Reference Standard IS 3156 ,with latest

amendments,

Standard CT Ratio (Amps/Amps) "

'200-100/1-1 ,. ,', "

100-50/1-1 .', "',

Rated continuous thermal current 120% of r,ated' primary ,"

,current "

Rted short time thermal primary current for 1 second 25'(in kA) " " "

.7. CT Characteristic:'.

' ,

a, Rated Pri":1ary Current(Amps)200.100 .

"

, 100:"50' "

b' Rated' SecondarYCurrent (Amps) 1c Accuracy Class 0.2d MaximumInstrumentSecurityFactor(lSF), <10 t

Rated Secondalj BU'rdem(VA) , '30' '

" e -,'..

8 ," eference Standard for insulating oil',', IS 335 with latesti' '. ' , amendments

;' .Specification ofPT (for CT-PT Set)1, Nominal System Voltage (kV rms) 33 , "

. '2 " t-Hghest System Voltage (kV rms)' " , 36 ,

3, Reference: standard IS' , 156 . with latest" amendments,

No. of Secondary Windings for potential m:asurel'T1et Two ' . "

devl«;:es ....$tandard Voltage Ratio : . ' 33kVN3/11 OV/v3'

, Rated Secondary Burden ,(VA),per winding 50 ,

,Accuracy Class (At 10% to 100% of rated VA burden) 02Rated Voltage Factor and Duration, 1.2'continuous and

" " 1.5 for 30' seconds "

, .- J\ ~

, '~30~2006, I

""'"

.-?""I):~~., . 'i\' ,,;,""'~: 638(51)

~OTE: Electroniagn~tic VTs may be used up to 220KV class.

D) Minimum a~ceptable specifications of 'dedicated single-phase' EHV 'potentlal. ..

,.

. E) , Minimum ~cceptable specificatlon$ of dedicated single-phase HV potentia~'transformers (PT) for metering

t r~~'~r~-~~!~~~a~~stem V~lt~g~~~~J~:; UU_'\ ;;kV . --~-~H~xv ' '_dJ

~_2 jtl~~~_est System V~I!~g~j~V rrns) J 36 __~__L!.?_~ ~i~, I i:\0terenceStandard' . . " 18'3156withratesfarnendrn~:n(~;:, , t-:: ---" '-" r;; ' '-'-"---"---'- '''___0'

',', l ;\~o. .')r Secondary \Njndiflg~ for pOf.ent~a!I T"NO ! '"{\',<)

:'('~;::;slJrern~jnt r.!a'.ljcf}$ i . :.. , ,-. .-' , --' dOd_d .-. , . - ..,,,.-. , -"-,, J._- -'c--''' -.'. ..,.. .. . . 00'" ,-_. "

8 Standard Voltage Ratio, (a) Windin-I 132kVN3' 1 220kV 1...J3I'

.

110V/...J3' '110Vl...J3 r

(b) Winding":11 '132kVN3 1 220kV/...J31

110V/...J3 110V/..J39 Rated Secondary Burden (VA)".

,(a)Windina-1 50 50 , ," . , ,

(b) Windina-II 50, ., 5010 Accuracv Class . '.

(f,I)Winding-I 0.2, ,(b) Windlna-II .. .0.211 Rated Voltaae Factor and Duration

(a) Windlna-I . 1.2 cOl)tlnuous and 1.5 for 30 seconds'(b) Wi,ndina-II 1.2 continuous and 1.5 for 30 seconds

'12 Reference Standard for Insulating IS .335with latest amendmentsoil . ,

,- --n.- -_n.-.- - . . - 0- n.. -----,

S.No. . Particulars 132kV' :220kV1 Nominal Svstem-Voltage (kV rms)

"132 220

2. Hiahest'Svstem Voltage (kV rms) 145 . 245, -'3 Reference Standard . IS 3156 with latest amendments.4 No. of Secondary Windings for. .potential Two ,Two. measurement devices5 Standard Voltae Ratio

'(a) Winding-I; .. 132kV/..J3' - 1 220kV/..J3 I ,

" .. ' ' 110V/..J3 '110Vl...J3

(b) Winding-II ' ,132kV/...J3 . I 220kV/..J3 ./.110Vlv3 110V/...J3.

6 Rated Secondary Burden (VA) .a)Winding-1 , 200 , 200

(b) Winding1I ." .' 50 '50. .

(c.) Winding-III.. ,

50 50.1

.,7 Accuracy Class "

a Winding-I','" 3P' "

b Winding-II . 0.2' '.

c Winding-III 0.2,8 Rated Voltage Factor and Duration

(a) Winding-I, 1.2. continuous and 1.5 for 30' . . seConds

(b) Winding-II 1.2 continuo,us and 1.5 for 30seconds:

9 . Reference Standard for insulating oil . IS 335 with latest amendments

'638 (52)

... -,..,. - -- - - ,- - - , -- 'C--.. ,.

, .

.' ~o,.f\ ~, ~ jo~ 2006

8.9.

I,

"'-'-

I '8..,10

-

. ". . . -

Te,sting Arrangements., . . , . .. .

8.9.1. ' The test term'inal blocks ,shall be 'provided' on all meters to faci,litate testing of. meters. Portable test set with high ,accuracy static source and ,5 times more'

"accurate' (or bett~r)electronic reference'stand!3rd meter.shafl.be used for testing.This mea'ns at least class 0.5$ reference standard meter for testing of ctas.s0.2S'meter, class 0.1S refer~nce 'standard'meter for testing of classO.5S meter and. .

class O.2Sref~rence met~rs for,testir)9 of cfass 1.QSmeter. These benches shall'also be used for checking and cali~rati.onof portable testing equipl1)ents.The " , .

aboveshai.1 be applicable for. laboratory testing of metel's, however, for site .'

,. '-, ;-", te~ting meter tes~ingequipments with"one "class higher accuracy than'meterunder test maybe us~das per provision of IS-12346-1999. . '." "

'.. '. '. .

8.9.2 Separate test-terminal 'blocksfor testh:tg'o{rhain and cheGk meters' shall be '. provided sothst when one meteri~ under testing:, the other metercontinu.es'to

. ,recordacb:Jal energy during testing period. Where only one/,main met!3r exists, an, . additional meter $hall be put in circuit during the testing pariod of th~ main me~er

,sothatwhile'the main met,er is under testing, the other meter can record energy, duringtheperiod~fmet~qmdertesting." .

. . .. . ' . . .' .

. Syst~ri1for ]olnt Ins.pec~lon,testing, calibratl!>n8.10, t ilie' meterhig'system located at meteringpoints betweengenerating plants, State'

'. tra,nsmissionutility and distribution'lic~nsees shall Deregularly'inspected; tested.'. . and calibrated at least once:In a y~ar (or at ari interval lesser than one year as .

, :. mutually agreed)'jointly by both the'agencies inv<;>lvedfor-dispatchand'receiptofenergy. Since the static trivector meters are calibrated through software at the.

. manufacturers' works, only accuracy oJ the' meters and functioning shall be .verified during joint inspection. In case of any doubt or defect, the meter shall,be' .replaced then and there or calibrated. In later 'case, error correction asdetermined will be applied to the meter reading for the purpose of billirig. Tocover for loss' of time, spare meters shall. always be kept available with theagen'cyto whom the meter/meteringpoint belongs. After testing, the meter shall

. 'be p(operly sealed and a joint report shall be prepared givil;g details'of testing'workcarried out, details of old seals removedand new seals affixed,test results,further action to be taken (it any) etc.' .

8.10.2 Joint inspection 'shall also' be carried out as and when differenc~ in meterreadings (so corrected)exce.edsthe sum of maximumerror as per accuracyclassof main and check meter. The meters shall' be jointly testedl calibrated on all '

loads and powerfac.tors as per releyant standards through static phantom load. .

-

.'

6 Standard Voltge Ratio' 33kVN3 I 1.1kV/..J3, I110Vl..J3 . . 110V/..J3

6 Rated Secondary Burden (VA) per winding' ,.100. 100a Winding-I . 100 . . 100. '

'(b) Winding-II. , 50 50(c) Winding-III . 50 50

7 Accuracy' Class(At 10% to 100% of r.ated '0.2. 0.2VA burden)' .la Winding-! 3P

,. ..b Winding-II 0.2 '. .

c Winding-III, 0.2..' ..

8 R!3tedVoltage Factor and Duration '1 2 continuous. and 1.5 for 30, . - seconds

".

~ ~'"

.(B.

~~~'ICP.~;'~ 30~ 2006

,. ,,\', ,

.''638 (53) ,

8;11 ,JVleterSealing Provision' ,. , .

" 8.11.1. M~tering systems shall.be jointly sealed by the ~i:Jthorlzedrepresentatives of theconcerned parties. T~e sea!h"!gof meter shall be arranged' as per the, provisions In'

CEA (Installation a~d Operation of M~ters), Regulation 2006~' '. '

. .

. 8.11.2 The register/record'of,thelssue of sea's and,sealing pliers, shall keep proper with the,.authorized perso~sto whomthese,areissued. .

"

. . ,, ,

, 8:11.3 No seal, applied pursuant to this meteririgcode, shall bE:!broken or removed except iq. " tne presence:~f:orwith the.prior consent of the agencyaffixlngottleseal'or on whose'

.behalf the seal, has, been affixed unless it is necessary' to do so. In circumstances',wh~re (i) both main. and check meters are malfunctioning' odhere occurs 'a fire or .'similar hazard and such removal is.essential and"such'consentcan norbe obtained.

, . " Im!TIediately(il) such ~ction.is required for the purpose of att~ridlng to the met,erfailure. In such circum~tances, v~rbai consent shall be given Immediately ~nd itf)1Qst'beconfirmed'in writingforthwith.. ' . . . ",'"

8.11.4. Sealing of the.met~rlri,g. system. $hall becarri~d our in, such.~'maJ1ner so as' notto .. ,,'~ tlt\lmperdownloading.of the data from the meter"usin'gCMRI,or a remote'meter

'. .reading system. ' . ' '., .,' ',' ".. ' .

..

-,

, 'Procedur~' for Assess~ent of C~nsumptlon'lnCa$eofDe~ectl~ea~diQr'Stuck-UpMeter,

, ~.12.1 Whenever a meter'goes, defective,the c~nsumpti()n' re~orded.bY the check' ~eter shall, '.. '.. be,referred,to for a period.agreed l1'!utuallybetweenthe user andthe STU.The details

of the malfunctioning along'with date,tlli1e aod snap-shot parameters along with 'loadsurVey ~tlaJi ,be retrieved frol11 the main meter. The exactqature. of maHLinctionirigshall be brought out after analyzing ,the data so retrieved and the consumption/losses'

. rec~rded ~y the main meter sh~il ~be,assessed accotdlngly.. .::'.'. . . ' '

8.12.2 ; If the~ain as we1las check'meterln~ systemsbe~m~ defeqtlve;,th~'assessmentof. energy con$umptionfor the outage not more thanweek period'shali be done by the' .

STU on basis of record. of substation where 'the Injection or.drawal take palace. If botI'L,:.."tHe meters. remain defective for more than one week then the grldcon'nectivitY shall be . .

, discontinued. .'. ' . . .', '

,~' 8.12

i.

"

, .

8.13 Replacement of defective or'stuck"up meter' , ,

A defective orstuck-~p mete~'shall be replacedas soon as possible.The owner qf the ~eter. . 'shall maintain spare InventorY~fmeters,so that down timeIs minimized. . , '

8.14MechanI81~;,fordispute resol~tlo~ ... . ,

Any disputes relating to 1nter;utility metering between State transmission utility and any'generating company/dis,ribution. licensees/users shall be settled In accordance with

, procedures given under', relevant power purchase agreements (PPA)/connection agreement, or relevant agreement, as the case may be. Incase of unresolved dispute, the matter mayl5ereferred to the Commjssion.:

, .- '

8.1~. To keep pace with continuousand fast up-gradationIn the technologyof meteringand. communication, the metering code needs to be reviewed periodically as per CEA Regulations/

gU,idelinesand the Commission'sdirectives from time to time. '. '

xxx

.

.., "

\I

, ,:, ~,

I\

. -, ,

,.

j.

.-...

.;,

, .'., "

'-r

ri

.,"

" Ii'

iI'\! ;

--- -