Table Of Contentइंटरनेट मानक
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in order to promote transparency and accountability in the working of every public authority,
and whereas the attached publication of the Bureau of Indian Standards is of particular interest
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education and knowledge, the attached public safety standard is made available to promote the
timely dissemination of this information in an accurate manner to the public.
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“The Right to Information, The Right to Live” “Step Out From the Old to the New”
IS 13010 (2002): ac Watthour Meters, Class 0.5, 1 and 2
[ETD 13: Equipment for Electrical Energy Measurement and
Load Control]
“!ान $ एक न’ भारत का +नम-ण”
Satyanarayan Gangaram Pitroda
““IInnvveenntt aa NNeeww IInnddiiaa UUssiinngg KKnnoowwlleeddggee””
“!ान एक ऐसा खजाना > जो कभी च0राया नहB जा सकता हहहहै””ै”
Bhartṛhari—Nītiśatakam
“Knowledge is such a treasure which cannot be stolen”
Is 13010:2002
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Indian Standard
ac WATTHOUR METERS, CLASS 0.5, 1 AND 2 —
SPECIFICATION
(First Revision )
ICS 17.220.20
0 BIS2002
BUREAU OF INDIAN STANDARDS
MANAK BHAVAN, 9 BAHADUR SHAH ZAFAR MARG
NEW DELHI 110002
SeDtember 2002 Price Group 9
Equipment for Electrical Energy Measurement and Load Control Sectional Committee, ET 13
FOREWORD
This Indian Standard (First Revision) wasadopted bythe Bureau ofIndian Standards, after the draft finalized by
the Equipment for Electrical Energy Measurement and Load Control Sectional Committee had been approved by
the Electrotechnical Division Council.
This standard was first published in 1990. This revision hasbeen brought outto update some ofthe requirements.
The test levels as specified inthis standard are regarded as minimum values to guarantee the proper fimctioning
of the meter under normal working conditions. For special applications other test levels might be necessary and
have to be fixed between the user and the manufacturer.
An explanatory note inrelation to watthour meters of Class 0.5 isgiven inAnnex A.
The following publications have also been referred to inthis standard:
a) IEC 60068-2-75 ( 1997)Environmental testing —Part 2-75: Tests—TestEh: Hammer tests.
b) 1S0 75-1:1993 Determination oftemperature ofdeflection under load— Part 1: General test method.
c) ISO 75-2:1993 Determination oftemperature ofdeflection under load— Part 2: Plastics and ebonite.
d) IEC 61000-4-5 ( 1995 ) Electromagnetic compatibility ( EMC ) — Part 4: Testing and measurement
techniques — Section 5 Surge immunity test.
e) IEC 60387 ( 1992-08 )Symbols foralternating-current electricity meters.
While preparing this standard, assistance hasbeen derived ffom IEC 60521 ( 1988) ‘Class0.5, 1and2alternating
current watthour meters’, issued bythe International Electrotechnical Commission’.
For the purpose of deciding whether aparticular requirement of this standard is complied with, the final value,
observed or calculated, expressing the result of a test or analysis, shall be rounded off in accordance with
IS2:1960 ‘Rules for rounding off numerical values (revised )’. The number ofsignificant places retained inthe
rounded off value should be the same as that of the specified value inthis standard.
,
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Is 13010:2002
Indian Standard
WATTHOUR METERS, CLASS 0.5, 1 AND 2 —
ac
SPECIFICATION
(First Revision )
1 SCOPE corresponding to different tariffs.
1.1 This standard applies only to induction type 3.4 Meter Rotor
watthour meters ofaccuracy Class0.5,1 and2,forthe
The moving element of the meter upon which the
measurement of alternating current electrical active
magnetic fluxes of fixed windings and of braking
energy.
elements act, and which operates the register.
1.2 Itappliestotheassemblyofmetersandaccessories,
3.5 Meter Driving Element
including current transformers, when enclosed inthe
meter case. It does not apply to maximum demand
Aworking part ofthe meter which produces atorque
indicators which iscovered byIS 8530.
bythe action of itsmagnetic fluxes upon the currents
induced in the moving element. It comprises
1.3 It does not apply to any kind of measuring
electromagnets withtheircontrol devicesandadjusting
devices such asthose used for telemetering electrical
devices.
energy covered by IS 14451 (Part 1).
1.4 This standard applies to multi-rate meters, but 3.6 Reverse Running Stop
does not apply to other special types of meters ( for
Amechanism to prevent reverse registration.
example, excess consumption meters ), or to meters
used for testing purposes covered by IS 11426. 3.7 Meter Braking Element
1.5 It does not apply to watthour meters where the Thepart ofthemeterwhich produces abraking torque
voltage across the connection terminals exceeds by the action of its magnetic flux upon the currents
600 V(line to line voltage for meters for polyphase induced inthe moving element. It comprises one or
systems ). more permanent magnets andtheir adjusting devices.
NOTE — For portable meters and meters foroutdoor 3.8 Register of Meter (Counting Mechanism)
use,additionalrequirementsmaybenecessary.
Thepartofthemeterwhichenablesthemeasuredvalue,
2 &ERENCES
that is, energy, to be registered.
2.1 The Indian Standards listed in Annex B are
3.9 Meter Base
necessary adjuncts to this standard.
The back ofthe meter by which it isgenerally fixed
3 TERMINOLOGY
and towhich are attached the frame, the terminals or
3.0 For the purpose of this standard, the following the terminal block and the cover.
definitions shall apply.
For a flush-mounted meter, itmay include the sides
3.1 Watthour Meter (Active Energy Meter) of the case.
An instrument which measures active energy by
3.9.1 Meter Socket
integrating active power with respect to time and
registers inwatthour or insuitable multiples thereof. Anenclosure withjaws toaccommodate terminals of
a ‘detachable meter and which has connectors from
3.2 Induction Meter
the termination ofthe circuit conductors, Itmaybe a
Ameter inwhich fluxes produced bycurrents infixed singleposition socketforonemeter oramulti-position
coils react with the eddy currents induced in a socket for two more meters.
conducting moving element,generallyasdisc(s),which
3.10 Meter Cover
causes the movement of the moving element.
Theenclosureontlont ofthemetermadeeitherwholly
~3 Multi-Rate Meter
oftransparent material orofopaque material provided
h energy meter provided with anumber ofregisters, with window(s) through which the movement of the
each becoming operative at specified time interva l rotor can be seen and the register can be read.
1
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Is 13010:2002
3.11 Meter Case current of the external circuit, to which the meter is
connected.
This comprises the base and the cover.
NOTE — When the meter incorporates a current
3.11.1 Insulating encased meter ofprotective Class transformer, the current circuit also includes the
1:Meter in which protection against electric shock transformer windings.
does not rely on basic insulation only, but which
3.18 Voltage Circuit
includes an additional safety precaution such that
conductive accessible parts are connected to the The windings of the driving element and internal
protective earthing conductor inthe fixed wiring of connections of the meter, supplied with the voltage
the installation in such a way that conductive of the circuit to which the meter isconnected.
accessible parts cannot become live inthe event of a
3.19 Auxiliary Circuit
failure ofthe basic insulation.
The element ( windings, lamps, contacts, etc. ) and
NOTE — This provision includes a protective earth
connections of an auxiliary device within the meter
terminal.
case intended to beconnected to an external device,
3.11.2 Insulating encased meter of protective for example, clock, relay and impulse counter.
Class 2: Meter with acase of insulating material in
3.20 Basic Current 1)(lb)
which protection against electric shock does not rely
onbasic insulation only,butinwhichadditional safety The value of current in accordance with which the
precautions, such asdouble insulation or reinforced relevant performance ofthe meter isfixed.
insulation, areprovided, there being noprovision for
3.21 Rated Maximum Current 1)(Imax )
protective earthing or reliance upon installation
conditions.
Thehighestvalueofcurrentatwhichthemeterpurports
to meet the accuracy requirements of this standard.
3.12 Meter Frame
3.22 Reference Voltagel)
The part to which are affixed the driving elements,
the rotor bearing, the register, usually the braking The value of voltage in accordance with which the
element and sometimes the adjusting devices. relevant performance ofthe meter isfixed.
3.13 Accessible Conducting Part 3.23 Reference Frequency
Aconductingpartwhichcanbetouchedbythestandard The value offrequency inaccordance with which the
test finger when the meter is installed ready for use. relevant performance ofthe meter isfixed.
NOTE — To determine whether a part is accessible, 3.24 Basic Speed ,.
eithervisualinspection shallbeused;ortheflexibletest .9
finger given inthe Fig.1ofIS 1401,or the rigid test The nominal speed ofrotation ofthe rotor expressed
finger given inFig.2of IS 1401shallbeapplied.In in revolutions per minute when the meter is under
caseofdoubt,thelattershallbeappliedwithamaximum reference conditions and carries basic current at
force of 30 N.
Cosm=l.
3.14 Protective Earth Terminal
3.25 Basic Torque
Theterminal connected toaccessible conducting parts
The nominal value oftorque onthe rotor atrest when
ofameter for connection tothe earth, for the sake of
themeter isunderreference conditions andwhenbasic
safety.
current isapplied atcos @= 1.
3.15 Terminal Block
3.26 Meter Constant
Asupport made of insulating material onwhich all or Constant expressing the relation between energy
someoftheterminals ofthemeteraregroupedtogether. registered by the meter and corresponding number
of revolutions of the rotor, expressed inrevolutions
3.16 Terminal Cover
per kilo watthour (rev/kWh ).
A cover which encloses the meter terminals and, if
3.27 Reference Temperature
required, the ends of the external wires or cables
connected to the terminals. The ambient temperature specified for reference
conditions.
3.17 Current Circuit
The winding of the driving element and the internal I)Theterms voltage andcurrent indicates lTllSVdUeS, Unks
connections of the meter through which flows the specified.
2
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Is 13010:2002
3.28 Clearance 3.34 Mean Temperature Coefficient
The shortest distance measured in air between Theratioofvariation ofpercentage errortothechange
conductive parts. oftemperature which produces this variation.
3.29 Creepage Distance 3.3S Vertical Working Position
The shortest distance measured over surface of The position of the meter in which the shaft of the
insulation between the conductive parts. rotor isvertical.
3.30 Percentage Error 3.36 Class Index +
I
The percentage error is given by the following A number which gives the limits ..of permissible
formula: percentage error, for all values of current, between
10percent oflb andlmax, for cos@= 1(and incase
R–A
Percentage error = — x 100 of polyphase meters with balanced load ) when the
A meter istested under reference conditions (including
permittedtolerancesonthereferencevalues) asdefined
where
in this standard.
R = energy registered by the meter, and
3.37 Classification Angle ( Degree of Phase
A = true energy. Displacement )
NOTE—Sincethetruevaluecannotbedetermined, it Thenominal phasedisplacement between voltage and
is approximated by a value with a stated uncertainty
current magnetic fluxes of a single driving element
that can be traced to standards agreed upon between
( see Note ) in principal air gaps when the voltage
manufacturer and user or to national standards vide
andcurrent applied tothis singleelement are inphase.
IS 12346.
When determined from the rotor speed, NOTE— Driving element includes any necessary
accessories,resistors,inductorsandshunts.
T– t
Percentage error =— Xloo” 3.38 ~pe
t
Designation used for defining aparticular design of
where
meter manufactured by one manufacturer, having:
T= true time, that is,the time acorrect meter a) similar metrological properties, ,..-.-,
would require for the same number of
revolutions of the rotor; and b) the same uniform construction of parts
determining these properties,
f = observed time for a given number of
revolutions of the rotor. c) the same number of ampere-turns for the
current winding atbasic current andthe same
The terms voltage and current indicates rms values, number’ of turns per volt, for the voltage
unless specified. winding at reference voltage,
3.31 Variation of Error Due to an Influence d) the sameratio ofthe rated maximum current
Quantity to the basic current, and
The difference between percentage errors of meter e) thesamevalueof basictorquewithatolerance ,
whenonlyoneinfluencequantityassumessuccessively of *10percent.
two specified values, oneofthem being the reference
They may have several values of basic current and
value,
several values ofreference voltage. These metes are
3.32 Influence Quantity orFactor designated bythemanufacturer byoneormore groups
ofletters ornumber, orofacombination ofletters and
Anyquantity oranyfactor, generallyexternaltometer,
numbers. Each type has one designation only.
which may affect the measured value.
NOTES
3.33 Distortion Factor
1Thetypeisrepresentedbythesamplemeter(s)intended
Theratioofrrnsvalueoftheharmoniccontent(obtained fortypetestsandwhosecharacteristics (basic currents
by subtracting from a non-sinusoidal alternating andreferencevoltage)arechosenfromthevaluesgiven
quantity, itsfi.mdamentalcomponent) tothermsvalue inTables 1and 2,proposed by the manufacturer.
ofthe non-sinusoidal quantity. The distortion factor 2 Where the number of ampere-turns would lead to
is usually expressed as a percentage. numberofturnsotherthanawholenumber,theproduct
3
Is 13010:2002
of the number ot’turns ofthe windings bythe value of where
the basic current may differ from that of the sample
Driving torque x 100
meter(s) representative of the type. It is advisable to Permanence factor =
choose thenextnumber immediately aboveorbelow in Rotor weight x Rotor speed
order to have whole number of turns. Only for this
Driving torque ising-cm;
reason maybe number ofturns pervolt ofthe voltage
windings differ, but bynotmore than 20percent from Rotor weight is ing;
that of the sample meters representative of the type.
Rotor speed is inrpm; and
3 Theratio ofthehighest tothelowest basic speed of
Voltage circuit power loss is inwatts.
the rotors toeach ofthe meters ofthe same type shall
L
not exceed 1:1.5. NOTE—Torqueandspeedcorrespond totherespective !
‘valuewhen the meter is under reference conditions,
3.39 Type Tests carrying thebasic current atunitypower factor. Power
loss in 2 voltage circuits is the average of the power
Tests carried out under prescribed conditions to
lossof2voltage circuits for3-wire meters andaverage
verify one of the characteristics of the type of the
of power loss of 3-voltdge circuits for 3-phase 4-wire
meter. systems.
3.39.1 Type Approval Procedure 4 CLASSIFICATION
The procedure according to which the series of type 4.1 Meters areclassifiedaccordingtotheirrespective
tests iscarried out on one meter or on small number classindices, forexample,0.5, 1or2.
of meters of the same type having identical
5 RATINGS
characteristics, selected bythemanufacturer, toveri~
thatthe respective type ofmeter complies withallthe 5.1 Standard Basic Currents
requirements of the standard for the relevant class
The basic currents shall be asgiven in Table 1.
of meters.
Table 1 Standard Basic Currents
3.39.2 Qualljication Procedure
(Clauses 3.38 wnd5.1 )
Theprocedure according towhichtypetestsarecarried
Type of Meter Basic Current ( Amps )
out on one meter or on a small number of meters of
thesametypehaving identical characteristics, selected (1) (2)
atrandom, toverify that the meter type hasno serious 1-phase 2.5, 5, 10, 15,20
systematic abnormalities .The precise tests and the
3-phase 5, 10,15,20, 30,40, 30
number ofmeterstobetested aretobeagreedbetween
For connection through lor5
the parties.
current transformer(s)
NOTE- Inpractice,it isconsideredthatnoserious
5.2 Rated Maximum Currents
systematicabnormalitiesexist when two out of three
meters tested comply with the relevant requirements Maximum rated current forwhole current meters shall
of this standard for the considered test.
bepreferably anintegral multiple ofthe basic current
3.40 Routine Tests ( that is four times the basic current ). The rated
maximum current ofmeter shall have the same value
Tests carried out on each meter to check conformity
astherated extended secondary current ofthe current
withtherequirements ofthisstandard inaspectswhich
transformer.
are likely to vary during production
5.3 Standard Reference Voltages
3.41 Acceptance Tests
The reference voltage shall be as given in Table 2
Tests carried out on all meters or on samples drawn (see IS 12360).
ffomabatch forthepurpose ofacceptance ofthebatch
Table2 Standard Reference Voltages ,.
during inspection by the purchaser.
(Clauses 3.38 and5.3 )
3.42 Optional Tests
Special test to be carried out, when required, by Meters for Standard Reference Exceptional
Voltage(V) Values(V)
agreement between the purchaser and the supplier.
(1) (2) (3)
3.43 Efficiency Factor
Direct connections 230( 400 ), 220( 380 ),
and through current 240( 415 ) 250( 433 )
Mathematically defined as :
transformer only
Permanence factor connection through 57.7( 100), 100(173 )
voltage transformer 63.5( 110 ), 200
Voltage circuit power loss
4
Is 13010:2002
5.4 Standard Frequency 6.2.3 Theholding onandsealing screws shall beheld
captive inthe meter cover when fixed from front.
Standard value for reference frequency is50Hz.
6.2.4 The case shall be soconstructed and arranged
6 GENERAL AND CONSTRUCTIONAL that anynon-permanent deformation cannot prevent
REQUIRENiENTS the satisfactory operation of the meter.
6.1 General 6.2.5 ThecaseofaClass0.5metershallbeconstructed
sothat, ifmounted according to the manufacturer’s
Meters shall be designed and constructed in such a
instructions, the meter shall not deviate by more
wayastoavoid introducing danger innormal useand
than 0.5° in all directions from its vertical position
normal conditions.
(see Note 2inTable 8).
— personal safety against electric shock,
6.2.6 The meters, having acase wholly or partially
made of metal, shall be provided with a protective
— personal safety against effects of excessive
earth terminal.
temperature,
6.3 Windows
— safety against spread of tire.
If the meter cover is not transparent, one or more
6.1.1 All parts which are subject to corrosion under
windows shall be provided for reading the register
normal working conditions shall be effectively
and observation of the rotor. These windows shall
protected against corrosion duetoatmospheric causes.
be covered by plates of transparent material which
Any protective coating shall not be liable to damage
cannot be removed without breaking the seals.
by ordinary handling nor injuriously affected by
exposure to air, under normal working conditions.
Theglassoranyothertransparent cover ofthewindow
shall be replaceable from inside only. The window
NOTE — For meters for special use in corrosive
atmosphere, additional requirements shall be fixed in cover shall be dust/moisture proof and shall not be
the purchased contract. removable from outside without damage.
6.1.2 The meter shall have adequate mechanical 6.4 Terminals—Terminal Block(s) and Protective
strength and shall withstand the fluctuations of EarthTerminal
temperature,whicharelikelytooccurinnormalworking
Terminals may be grouped in one or more terminal
conditions,
block(s) having adequate insulating properties and
6.1.3 The components shall bereliably fastened and mechanical strength. In order to satisfy such
secured against loosening. requirements, when choosing insulating materials for
the terminal block(s), adequate testing of materials
6.1.4 The electrical connections shall be such asto should betaken into account. The material of which
prevent any opening of the circuit under normal theterminal block ismade shallbecapable ofpassing
conditions ofuse, including anyoverload conditions the tests given in1S0 standard 75for temperature of
specified inthis standard. 135‘c.
6.1.5 The construction of the meter shall be such as The holes in the insulating material which form a
tominimizetherisksofshort-circuitingoftheinsulation prolongation oftheterminal holes shallbeofsufficient
between live parts and accessible conducting parts sizeto accommodate the insulation ofthe conductors
duetoaccidental looseningorunscrewingofthewiring, also,
screws, etc.
NOTE—Whetherthedisconnectingdeviceforthemeter
6.1.6 The meter shall not produce appreciable noise voltage circuit will be inthe terminal compartment or
in use. inside the meter cover, shall be amatter of agreement
betweenthema&rfacturer andthepurchaser. However,
6.2 Case ifthetest faciIity permits, itmayalsobe agreed bythe
parties todispense with such disconnecting device, so
that voltage terminal(s) may be connected firmly to
6.2.1 Themetershallhaveareasonably dust/moisture-
theinputcurrentterminal(s)andcannotbedisconnected
proof case, which may be sealed in such away that
easily.
the internal parts ofthe meter areaccessible onlyafter
breaking the seals. 6.4.1 Fixing of Conductors
6.2.2 The cover shall not be removable without the The manner of fixing the conductors tothe terminals
use of tool, coin or any similar device. shallensureadequate anddurable contact toeliminate
5
