Disclosure to Promote the Right To Information

Whereas the Parliament of India has set out to provide a practical regime of right to information for citizens to secure access to information under the control of public authorities, 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 to the public, particularly disadvantaged communities and those engaged in the pursuit of 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.

इंटरनेट मानक

“!ान $ एक न' भारत का +नम-ण”Satyanarayan Gangaram Pitroda

“Invent a New India Using Knowledge”

“प0रा1 को छोड न' 5 तरफ”Jawaharlal Nehru

“Step Out From the Old to the New”

“जान1 का अ+धकार, जी1 का अ+धकार”Mazdoor Kisan Shakti Sangathan

“The Right to Information, The Right to Live”

“!ान एक ऐसा खजाना > जो कभी च0राया नहB जा सकता है”Bhartṛhari—Nītiśatakam

“Knowledge is such a treasure which cannot be stolen”

“Invent a New India Using Knowledge”

है”ह”ह

IS 1885-85 (2003): Electrotechnical Vocabulary, Part 85:Electromagnetic Compatibility [LITD 9: ElectromagneticCompatibility]

IS 1885 (Part 85) :2003IEC 60050 (161) (1990)

[Superseding IS 1885 (Part 36): 1972,IS 1885 (Part 64/See 1) :1987 and

IS 1885 (Part 64/See 2) : 1987]

Indian Standard

ELECTROTECHNICAL VOCABULARY

PART 85 ELECTROMAGNETIC COMPATIBILITY

ICS 29.020

0 BIS 2003

BUREAU OF INDIAN STANDARDSMANAK BHAVAN, 9 BAHADUR SHAH ZAFAR MARG

NEW DELHI 110002

September 2003 Price Group 8

Electromagnetic Compatibility $ectional Committee, LTD 22

NATIONAL FOREWORD

This Indian Standard (Part 85) which is identical with IEC 60050 (161) (1990) ‘International ElectrotechnicalVocabulary — Chapter 161 Electromagnetic compatibility’ issued by the International ElectrotechnicalCommission (IEC) was adopted by the Bureau of Indian Standards on the recommendation of the ElectromagneticCompatibility Sectional Committee and approval of the Electronics and Telecommunication Division Coi.mcil.

This Indian Standard (Part 85) supersedes following Indian Standards:

1S 1885 (Part 36) : 1972 Electrotechnical vocabulary : Part 36 Radio interference.

IS 1885 (Part 64/See 1) :1987 Electrotechnical vocabulary : Part 64 Electromagnetic compatibility,Section 1 General terms.

1S 1885 (Part 64/See 2) :1987 Electrotechnical vocabulary : Part 64 Electromagnetic Compatibility,Section 2 Specific terms.

In the adopted standard, certain conventions are not identical to those used in Indian Standards. Attention isparticularly drawn to the following:

Wherever the words ‘International Standard’ appear referring to this standard, they should be read as<Indian Standard’.

Amendment No. 2 to the above International Standard has been incorporated.

Only the English language text of the International Standard has beefi retained while adopting it in this IndianStandard.

IS 1885 (Part 85): 2003

161-01-01(702-08-65)

161-01-02

161-01-03(702-08-02)

161-01-04(702-08-30)

161-01-05(702-08-04)

161-01-06(702-08-29)

161-01-07(702-08-66)

161-01-08

161-01-09(702-02-05)

161-01-10(702-02-07)

IEC 60050(161)(1990)

Indian Standard

ELECTROTECHNICAL VOCABULARYPART 85 ELECTROMAGNETIC COMPATIBILITY

SECTION 161-01- BASIC CONCEPTS

electromagnetic environmentThe totality of electromagnetic phenomena existing at a given location.

electromagnetic noiseA time-varying electromagnetic phenomenon apparently not conveying information andwhich may be superimposed on or combined with a wanted signal.

unwanted signalundesired signalA signal that may impair the reception of a wanted signal.

interfering signalA signal that impairs the reception of a wanted signal.

electromagnetic disturbanceAny electromagnetic phenomenon which may degrade the performance of a device,equipment or system, or adversely affect living or inert matter.

NOTE — An electromagnetic disturbance may bean electromagnetic noise, an unwanted signal or a changein the propagation medium itself.

electromagnetic interferenceEMI (abbreviation)Degradation of the performance of an equipment, transmission channel or system causedby an electromagnetic disturbance.NOTE — The English words “interference” and “disturbance” are often used indiscriminate y.

electromagnetic compatibilityEMC (abbreviation)The ability of an equipment or system to function satisfactorily in its electromagneticenvironment without introducing intolerable, electromagnetic disturbances to anythingin that environment.

(electromagnetic) emissionThe phenomenon by which electromagnetic energy emanates from a source.

emission (in radiocommunication)Radio waves or signals produced by a radio transmitting station.NOTES

1 In radio communication the term “emission” should not be used in the more general sense of “radio frequencyemission”. For example that part of electromagnetic energy from the local oscillator of a radio receivertransferred to external space, is a radiation and not an emission.

2 In radiocommunication, the French term “emission” applies only to intentional radiation.

(electromagnetic ) radiation1. The phenomenon by which energy in the form of electromagnetic waves emanatesfrom a source into space.2. Energy transferred through space in the form of electromagnetic waves.

NOTE — By extension, the term “electromagnetic radiation” sometimes also covers induction phenomena.

1

‘IS 1885 (Part 85) :2003IEC 60050 (161) (1990)

161-01-11 radio environment1. The electromagnetic environment in the radio frequency range.2. The totality of electromagnetic fields created at a given location by operating radiotransmitters.

161-01-12.(702-08-05)

161-01-13(702-08-06)

161-01-14

161-01-15

161-01-16

161-01-17(702-08-11)

161-01-18(702-08-12)

161-01-19

161-01-20

161-01-21

161-01-22

161-01-23

radio (frequency) noiseElectromagnetic noise having components in the radio frequency range.

radio (frequency) disturbanceElectromagnetic disturbance having components in the radio frequency range.

radio frequency interferenceRFI (abbreviation)Degradation of the reception of a wanted signal caused by radio frequency.

NOTE – The English.words “interference” and “disturbance” are often used indiscriminately. The expression“radio frequency interference” is also commonly applied to a radio frequency disturbance or an unwantedsignal.

inter-system interferenceElectromagnetic interference in one system due to an electromagnetic disturbanceproduced by another system.

intra-system interferenceElectromagnetic interference occurring in a system due to an electromagnetic disturbanceproduced within the same system.

natural noiseElectromagnetic noise having its source in natural phenomena and not generated by man-made devices.

man-made noiseElectromagnetic noise having its source in man-made devices.

degradation (of performance)An undesired departure in the operation performance of any device, equipment or systemfrom its intended performance.

NOTE — The term “degradation” can apply to temporary or permanent faihsre.

immunity (to a disturbance)The ability of a device, equipment or system to perform without degradation in thepresence of an electromagnetic disturbance.

(electromagnetic) susceptibilityThe inability of a device, equipment or system to perform without degradation in thepresence of an electromagnetic disturbance.

NOTE — Susceptibility is a lack of immunity.

electrostatic dischargeESD (abbreviation)A transfer of electric charge between bodies of different electrostatic potential in proximityor through direct contact.

emitter (of electromagnetic disturbance)Device, equipment or system which gives rise to voltages, currents or electromagneticfields that can act as electromagnetic disturbances.

2

IS 1885 (Part 85) :2003IEC 60050 (161) (1990)

.

161-01-24

161-02-01(702-07-78)

161-02-02(702-03-01)

161-02-03

161-02-04

161-02-05(702-03-05)

161-02-06

161-02-07

161-02-08(702-08-07)

161-02-09

161-02-10(702-08-09)

161-02-11

161-02-12(702-08-10)

161-02-13

susceptible deviceDevice, equipment or system whose performance can be degraded by an electromagneticdisturbance.

SECTION 161-02- DISTURBANCE WAVEFORMS

transient (adjective and noun)Pertaining to or designating a phenomenon or a quantity which varies between twoconsecutive steady states during a time interval short compared with the time-scale ofinterest.

PulseAn abrupt variation of short duration of a physical quantity followed by a rapid return tothe initial value.

ImpulseA pulse that, for a given application, approximates a unit pulse or a Dirac function.

SpikeAn unidirectional pulse of relatively short duration.

risetime (of a pulse)The interval of time between the instants at which the instantaneous value of a pulse firstreaches a specified lower value and then a specified upper value.

NOTE — Unless otherwise specified, the lower and upper values are fixed at 10% and 90% of the pulsemagnitude.

rate of riseThe average rate of change with time over a defined interval of values of a quantity, e.g.,between 10% and 90% of its peak value.

Burst (of pulses or oscillations)A sequence of a limited number of distinct pulses or an oscillation of limited duration.

impulsive noiseNoise which, when incident on a particular equipment, manifests itself as a succession ofdistinct pulses or transients.

impulsive disturbanceElectromagnetic disturbance which, when incident on a particular device or equipment,manifests itself as a succession of distinct pulses or transients.

continuous noiseNoise the effects of which on a particular equipment cannot be resolved into a successionof distinct effects.

continuous disturbanceElectromagnetic disturbance the effects of which on a particular device or equipmentcannot be resolved into a succession of distinct effects.

quasi-impulsive noiseNoise equivalent to a superposition of impulsive noise and continuous noise.

discontinuous interferenceElectromagnetic interference occurring during certain time intervals separated byinterference-free intervals

3

IS 1885 (Part 85) :2003IEC 60050 (161) (1990)

161-02-14(702-08-38)

161-02-15

161-02-16

161-02-17(MOD 101-04-38)

161-02-18(MOD 101-04-39)

161-02-19

161-02-20

161-02-21(MOD 101-04-42)

161-02-22(MOD 131-03-03)

161-02-23(MOD 131-03-04)

161-02-24(101-04-34)

161-02-25(MOD 131-03-09)

161-02-26(MOD 131-03-14)

161-02-27

161-02-28

random noiseNoise the values of which at given instants are not predictable.

ClickAn electromagnetic disturbance which, when measured in a specified way, has a durationnot exceeding a specified value.

click rateThe number of clicks per unit of time, generally per minute, that exceed a specified level.

fundamental (component)The component of order 1 of the Fourier series of a periodic quantity.

harmonic (component)A component of order greater than 1 of the Fourier series of a periodic quantity.

harmonic numberharmonic orderThe integral number given by the ratio of the frequency of a harmonic to the fundamentalfrequency.

nth harmonic ratioThe ratio of the r.m.s. value of the.nth harmonic to that of the fundamental component.

harmonic contentThe quantity obtained by subtracting the fimdamental component from an alternatingquantity.

fundamental factorThe ratio of the r.m,s. value of the fundamental component to the r.m.s. value of analternating quantity.

(total) harmonic factorThe ratio of the r.m.s. value of harmonic content to the r.m.s. value of an alternatingquantity.

PulsatingApplies to a periodic quantity of non-zero mean value.

ripple contentalternating componentThe quantity derived by removing the direct component from a pulsating quantity.

peak-ripple factorThe ratio of the peak-to-valley value of the ripple content to the absolute value of thedirect component of a pulsating quantity.

r.m.s.-ripple -factorThe ratio of the r.m.s. value of the ripple content to the absolute value of the directcomponent of a pulsating quantity.

discontinuous disturbanceElectromagnetic disturbance, the effects of which on a particular device or equipmentcan be resolved into a succession of distinct-effects.

NOTE— It is recognized that this definition does not characterize the disturbance independently of the effect

that .it produces. As a practical matter, any measure of a disturbance should be relatable to its effect on asusceptible device.

4

IS 1885 (Part 85) :2003IEC 60050 (161) (1990)

161-02-29 damped oscillatory waveA damped oscillation.

NOTE -In EMCthis temiscommonly used forwaves having a frequency between 100kHzand a fewmegahertz andwhose damping time constant is five periods or more.

161-02-30 ring waveA damped oscillation whose damping time constant is of the order of one period.

SECTION 161-03- INTERFERENCE CONTROL RELATED TERMS

161-03-01 level (of a time varying quantity)(702-02-09) A mean or otherwise weighted value of a time varying quantity, such as a power or a

field quantity, evaluated in a specified manner during a specified time interval.

NOTE—The level of a quantity may be expressed in logarithmic units, for example, in decibels with respectto a reference value.

161-03-02

161-03-03

161-03-04

161-03-05

161-03-06

161-03-07

161-03-08

161-03-09

161-03-10

mains-borne disturbanceElectromagnetic disturbance conducted to a device via the lead connecting it to a powersupply.

mains immunityImmunity from mains-borne disturbance.

mains decoupling factorThe ratio of a voltage applied at a specified point of the mains to a corresponding voltageapplied at a specified input port of a device that yields the same disturbing effect to thatdevice.

cabinet radiationRadiation from an enclosure containing equipment, excluding radiation from connectedantennas or cables.

internal immunityAbility of a device, equipment or system to perform without degradation in the presenceof electromagnetic disturbances appearing at its normal input terminals or antennas.

external immunityAbility of a device, equipment or system to perform without degradation in the presenceof electromagnetic disturbances entering other than via its normal input terminals orantennas.

limit of disturbanceThe maximum permissible electromagnetic disturbance level, as measured in a specifiedway.

limit of interferenceMaximum permissible degradation of the performance of a device, equipment or systemdue to an electromagnetic disturbance.

NOTE—Because of the difficulty of measuring interference in many systems, frequently the term “limits ofinterference” is used in English instead of “limit of disturbance”.

(electromagnetic) compatibility levelThe specified maximum electromagnetic disturbance level expected to be impressed ona device, equipment or system operated in a particular conditions.

5

IS 1885 (Part 85) :2003[EC 60050 (161) (1990)

161-03-11

161-03-12

161-03-13

161-03-14

161-03-15

161-03-16

161-03-17

161-03-18

161-03-19

161-03-20

161-03-21

161-03-22

161-03-23

NOTE— In practice the electromagnetic compatibility level is not an absolute maximum level but may be

exceeded by a small probability.

emission level (of a disturbing source)The level of a given electromagnetic disturbance emitted from a particular device,equipment or system, measured in a specified way.

emission limit (from a disturbing source)The specified maximum emission level of a source of electromagnetic disturbance.

emission marginThe difference between the electromagnetic compatibility level and the emission limitfor a device, equipment or system.

immunity testThe maximum level of a given electromagnetic disturbance incident on a particular device,equipment or system for which it remains capable of operating at a required degree ofperformance.

immunity limitThe specified minimum immunity level.

immunity marginThe difference between the immunity limit of.a device, equipment or system and theelectromagnetic compatibility level.

(electromagnetic) compatibility marginThe difference between the immunity level of a device, equipment or system and theemission limit from the disturbance source.

coupling factorThe ratio of an electromagnetic quantity, usually voltage or current, appearing at a specifiedlocation of a given circuit to the corresponding quantity at a specified location in thecircuit from which energy is transfemed by coupling.

NOTE—The term “coupling” is defined in chapter 131 and 726.

coupling pathThe path over which part or all of the electromagnetic energy from a specified source istransferred to another circuit or device.

-earth-coupled interferenceground-coupled interference (USA)Electromagnetic interference resulting from an electromagnetic disturbance coupled fromone circuit to another through a common earth or ground return path.

earthing inductorgrounding inductor (USA)An inductor connected in series with the earthing conductor of an appliance.

disturbance suppressionAction which reduces or eliminates electromagnetic disturbance.

interference suppressionAction which reduces or eliminates electromagnetic interference,

6

IS 1885 (Part 85) :2003IEC 60050 (161) (1990)

161-03-24

161-03-25(151-01-13)

161-03-26(151-01-16)

161-04-01

161-04-02

161-04-03

161-04-04

161-04-05

161-04-06

161-04-07

suppressorsuppression componentA component specially designed for disturbance suppression.

ScreenA device used to reduce the penetration of a field into an.assigned region.

electromagnetic screenA screen of conductive material intended to reduce the penetration of a varyingelectromagnetic field into an assigned region.

SECTION 161-04- MEASUREMENTS

disturbance voltageinterference voltage (deprecated in this sense)Voltage produced between two points on two separate conductors by an electromagneticdisturbance, measured under specified conditions.

disturbance field strengthinterference field strength (deprecated in this sense)The field strength produced at a given location by an electromagnetic disturbance,measured under specified conditions.

disturbance powerinterference power (deprecated in this sense)Electromagnetic disturbance power, measured under specified conditions.

reference impedanceAn impedance of specified value used in the calculation or measurement of theelectromagnetic disturbance caused by an appliance.

artificial mains networkline impedance stabilization networkLISN (abbreviation) (USA)A network inserted in the supply mains lead of apparatus to be tested which provides, ina given frequency range, a specified load impedance for the measurement of disturbancevoltages and which may isolate the apparatus from the supply mains in that frequencyrange.

delta networkAn artificial mains network enabling the common mode and differential mode voltagesof a single phase circuit to be measured separately.

V-networkAn artificial mains network enabling the voltages between each conductor and earth tobe measured separately.

NOTE— The V-network may be designed for application to networks of any number of conductors.

161-04-08 differential mode voltagesymmetrical voltageThe voltage between any two of a specified set of active conductors.

161-04-09 common mode voltageasymmetrical voltageThe mean of the phasor voltages appearing between each conductor and a specifiedreference, usually earth or frame.

7

IS 1885 (Part 85) :2003IEC 60050 (161) (1990)

161-04-10 common mode conversionThe process by which a differential mode voltage is produced in response to a.commonmode voltage.

161-04-11 symmetrical terminal voltageDifferential mode voltage, measured by means of a delta network at specified terminals.

161-04-12 asymmetrical terminal voltageCommon mode voltage measured by means of a delta network at specified terminals.

161-04-13 V-terminal voltageTerminal voltage, measured between a mains conductor and earth, in a V-network.

161-04-14 transfer impedance (of a screened circuit)The quotient ofthe voltage appearing between two specified points in the screened circuitby the current in a defined cross-section of the screen.

161-04-15 surface transfer impedance (of a coaxial line)The quotient of the voltage induced in the centre conductor of a coaxial line per unitlength by the current on the external surface of the coaxial line.

161-04-16 effective radiated power (of any device in a given direction)The power required at the input of a lossless reference antenna to produce, in a givendirection at any specified distance, the same power flux density as that radiated by agiven device.

NOTE— For the ITU and in.Chapter 712, the term “effective radiated power” without qualification is usedonly when the reference antenna is a half-wave dipole.

161-04-17

161-04-18

161-04-19

161-04-20

161-04-21

161-04-22

electrical charge time constant (of a detector)The time required, after the instantaneous application of a sinusoidal input voltage, at itsdesigned input frequency, for the output voltage of a detector to reach (1-l/e) of itssteady-state value.

electrical discharge time constant (of a detector)The time required, after the instantaneous removal of a sinusoidal input voltage, for theoutput voltage of a detector to fall to l/e of its initial value.

mechanical time constant (of an indicating instrument)The quotient of the period of free oscillation of an indicating measuring instrument by 27c.

NOTE — Free oscillation characterizes the movement that would occur in the absence of any damping.

overload factor (of a receiver)The ratio of the maximum amplitude of a sinusoidal input signal to the value correspondingto fill-scale deflection of the indicating instrument, for which the amplitude/amplitudecharacteristics of the predetector circuits of a receiver do not depart from linearity bymore than 1 dB.

quasi-peak detectorA detector having specified electrical time constants which, when regularly repeatedidentical pulses are applied to it, delivers an output voltage which is a fraction of thepeak value of the pulses, the fraction increasing towards unity as the pulse repetition rateis increased.

quasi-peak voltmeterThe combination of a quasi-peak detector coupled to an indicating instrument having a

8

IS 1885 (Part 85) :2003IEC 60050 (161) (1990)

161-04-23

161-04-24

161-04-25

161-04-26

161-04-28

161-04-29

specified mechanical time constant.pulse response characteristic (of a quasi-peak voltmeter)The relationship between the indication of a quasi-peak voltmeter and the repetition rateof regularly repeated identical pulses.

peak detectorA detector, the output voltage of which is the peak value of an applied signal.

root-mean-square detectorA detector, the output voltage of which is the r.m.s. value of an applied signal.

NOTE — The r.m.s. value must be taken over a specified time interval.

average detectorA detector the output voltage of which is the average value of the envelope of an appliedsignal.

NOTE — The average value must be taken over a specified time interval.

161-04-27 artificial handAn eIectric network simulating the impedance of the human body under averageoperational conditions between a hand-held electrical appliance and earth.

(radiation) test siteA site meeting requirements necessary for correctly measuring, under defined conditions,electromagnetic fields emitted.by a device under test.

stop (quarter-.wave) filterA tuned movable coaxial structure set around a conductor in order to limit the radiatinglength of the conductor at a given frequency.

161-04-30

161-04-31

161-04-32

161-04-33

161-04-34

161-04-35

NOTE— A stop quarter-wave filter is a special case of the “quarter-wave choke” defined in chapter 712.

absorbing clampA measur;ng de;ice, movable along the mains lead of an appliance or similar device,intended to assess the maximum radio frequency power emitted by the appliance ordevice.

striplineA terminated transmission line consisting of two parallel plates between which a wave ispropagated in the transverse electromagnetic mode to produce a specified field for testingpurposes.

TEM cellAn enclosed system, often a rectangular coaxial line, in which a wave is propagated inthe transverse electromagnetic mode to produce a specified field for testing purposes.

dummy lampA device simulating the radio frequency impedance of a fluorescent lamp and soconstructed that it can replace the fluorescent lamp in a luminaire for the purpose ofluminaire insertion loss measurement.

balunA device for transforming an unbalanced voltage to a balanced voltage or vice-versa.

current probeA device for measuring the current in a conductor without interrupting the conductor andwithout introducing significant impedance into the associated circuits.

9

IS 1885 (Part 85) :2003IEC 60050 (161) (1990)

161-04-36 ground (reference) planeA flat conductive surface whose potential is used as a common reference.

161-04-37 shielded enclosurescreened roomA mesh or sheet metallic housing designed expressly for the purpose of separatingelectromagnetically the internal the external environment.

161-04-38

161-04-39

161-04-40

161-04-41

161-05-01

161-05-02

161-05-03

161-05-04(CISPR 22)

161-05-05

differential mode currentIn a two-conductor cable, or for two particular conductors in a multi-conductor cable,half the magnitude of the difference of the phasor representing the currents in eachconductor.

common mode currentIn a cable having more than one conductor, including shields and screens if any, themagnitude of the sum of the phasors representing the cuments in each conductor.

common mode impedanceThe quotient of the common mode voltage by the-common mode current.

immunity test levelseverity level (deprecated)The level of a test signal used to simulate an electromagnetic disturbance when performingan immunity test.

SECTION 161-05- EQUIPMENT CLASSIFICATION

ISM (qualifier)Qualifies equipment or appliances designed to generate and use locally radio frequencyenergy for industrial, scientific, medical, domestic or similar purposes, excludingapplications in the field of telecommunications.

NOTES1 The acronym lSM derives from “industrial, scientific and medical”.2 In some organizations, information technology equipment is excluded.

radio frequency heating apparatusISM equipment designed to produce a heating effect by the use of radio frequency energy.

MM-frequency bandA frequency band allocated for use by ISM equipment.

Information technology equipmentITE (abbreviation)Equipment designed for the purpose ofa) receiving data from an external source (such as, a data input line or via a keyboard);

b) performing some processing functions on the received data (such as, computation,data transformation or recording, filing, sorting, storage, transfer of data);

c) providing a data output (either to other equipment or by the reproduction of data orimages).

NOTE—This definition includes electrical or electronic units or systems wh:ch predominantly generate amultiplicity of periodic binary pulsed electrical or electronic waveforms and are designed to perform dataprocessing functions such as word processing, electronic computation, data transformation, recording, tiling,sorting, storage, retrieval and transfer, and reproduction of data as images.

professional equipmentEquipment for use in trades, professions or industries and which is not intended for sale

10

IS 1885 (Part 85) :2003IEC 60050 (161) (1990)

161-06-01(RR 139)

161-06-02(RR 138)

161-06-03

161-06-04

161-06-05

161-06-06

161-06-07

161-06-08(702-08-24)

to the general public.

NOTE—For some applications, professional equipment must be identified as such by the manufacturer.

SECTION 161-06- RECEIVER AND TRANSMITTER TERMS

spurious emission (of a transmitting station)Emission on a frequency or frequencies wti~chare outside the necessary bandwidth andthe level of which maybe reduced without affecting the corresponding transmission ofinformation, Spurious emissions include harmonic emissions, parasitic emissions,intermodulation products and frequency conversion products, but exclude out-of-bandemissions.NOTES1 Necessary bandwidth is defined in Radio Regulation 146.

2 The English word “emission” used here has the sense defined in 161-01-09

out-of-band emissionEmission on a frequency or frequencies immediately outside the necessary bandwidthwhich results from the modulation process, but excluding spurious emissions.

signal-to-disturbance ratioThe ratio of the wartted signal level to the electromagnetic disturbance level as measuredunder specified conditions.NOTE– TheTerm“signa[-to-interferenceratio”isdeprecatedinthesenseof“signal-to-disturbanceratio”.

signal-to-noise ratioThe ratio of the wanted signal level to the electromagnetic noise level as measured underspecified conditions.

protection ratioThe minimum value of the signal-to-disturbance ratio required to achieve a specifiedperformance of a device or equipment.

spurious response frequencyThe frequency of an electromagnetic disturbance at which an unintended response froma given equipment may be obtained.

NOTE – In the case of a receiver tuned to frequency fO, many spurious response frequencies f, may be foundfrom the following formulae:

f, = (l/m) (n f, * f,)

or f, = folh

where

fL = Ioeal oscillator frequency,

f, = intermediate frequency,

m, n, h = integers.

spurious response rejection ratioThe ratio of the level of a specified signal at a spurious response frequency, producing aspecified output power from an equipment, to the level of the wanted signal producingthe same output power.

parasitic oscillationAn unwanted oscillation produced in an equipment at a frequency independent both ofthe operating frequencies and of frequencies related to the generation of desiredoscillations.

11

IS 1885 (Part 85) :2003IEC 60050 (161) (1990)

161-06-09(702-01-14)

161-06-10

161-06-11

161-06-12

161-06-13

161-06-14

161-06-15

161-06-16

161-06-17

161-06-18

161-06-19(702-08-35)

161-06-20(702-07-64)

-bandwidth (of a device)The width of a frequency band over which a given characteristic of an equipment ortransmission channel does not differ from its reference value by more than a specifiedamount or ratio.

NOTE - The given characteristic may be, for example, the ampiitude/frequency characteristic, the phase/frequency characteristic or the delay/frequency characteristic.

bandwidth (of an emission or signal)The width of the frequency band outside which the level of any spectral component doesnot exceed a specified percentage of a reference level.

broadband disturbanceAn electromagnetic disturbance which has a bandwidth greater than that of a particularmeasuring apparatus, receiver or susceptible device.

NOTE — For some purpose particular spectral components of a broadband disturbance may be considered as

narrowband disturbances.

-broadband deviceA device whose bandwidth is such that it is able to accept and process all the spectralcomponents of a particular emission.

narrowband emissionAn electromagnetic disturbance, or spectral component thereof, which hasit bandwidthless than or equal to that of a particular measuring apparatus, receiver or susceptibledevice.

narrowband deviceA device whose bandwidth is such that is ableto accept and process only a portion of thespectral components of a particular emission.

selectivityThe ability or a measure of the ability of a receiver to discriminate between a givenwanted signal and unwanted signals.

effective selectivitySelectivity under specified special conditions such as when receiver input circuits areoverloaded.

adjacent channel selectivityThe selectivity measured with a signal spacing equal to the channel spacing.

desensitizationA reduction of the wanted output of a receiver due to an unwanted signal.

crossmodulationModulation of the carrier of a wanted signal by an unwanted signal, produced byinteraction of the signals in non-linear equipment, electrical networks or transmissionmedia.

intermodulationA process occurring in a non-linear device or transmission medium whereby the spectralcomponents of the input signal or signals interact to produce new components having

● frequencies equal to linear combinations with integral coefficients of the frequencies ofthe input components.

12

IS 1885 (Part 85) :2003IEC 60050 (161) (1990)

161-06-21

161-06-22

161-06-23

161-06-24

NOTE—lntemodulation mayresult from asingle non-sinusoidal input signal or fromseveral sinusoidal ornon-sinusoidal signals applied to the same or to different inputs.

intermediate frequency rejection ratioThe ratio of the level of a specified signal at any intermediate frequency used in a receiverto the level of the wanted signal producing equal output powers.

image rejection ratioThe ratio of the level of a specified signal at the image frequency of a receiver to thelevel of a signal at the tuned frequency, producing equal output.powers.

single-signal methodA method of measurement in which the response of a receiver to an unwanted signal ismeasured in the absence of the wanted signal.

two-signal methodA method of measurement that determines the response of a receiver to an unwantedsignal in the presence of the wanted signal.

NOTE— For this method, the detailed test procedure and the criterion to use must be defined for each typeof receiver tested.

SECTION 161-07- POWER CONTROLS AND SUPPLY NETWORK IMPEDANCES

161-07-01 input power controlThe regulation of the electric power supplied to an apparatus, machine or system toachieve the required performance.

161-07-02

161-07-03

161-07-04

161-07-05

161-07-06

161-07-07

output power controlThe regulation of the electric power supplied from an apparatus, machine or system toachieve the required performance.

cyclic on/off switching controlA power control which operates to switch the supply to an equipment on and off in arepetitive manner.

program (of a control system)A set of command and information signals necessary for the achievement of a specificsequence of operations.

multicycle control (by ha}f-cycles)The process of varying the ratio of the number of half-cycles of current conduction to thenumber of half-cycles of non-conduction.

NOTE—The various combinations of times of conduction and non-conduction enable, for example, theaverage power supplied to the controlled load to be varied.

synchronous multicycle controlMulticycle control in which the starting and stopping instants of the conduction intervalsare synchronized with respect to the instantaneous values of line voltage.

burst firing controlSynchronous multicycle control in which the starting instant is synchronized at voltagezero and current flows for an integral number of complete half-cycles.

NOTE— Burst tiring control is employed with resistive loads.

13

IS 1885 (Part 85) :2003IEC 60050(161)(1990)

161-07-08 generalized phase controlThe process of varying, within the cycle or half-cycle of the supply voltage, the timeinterval or intervals during which current conduction occurs.

161-07-09 phase controlThe process of varying, within the cycle or half-cycle of the supply voltage, the instant atwhich current conduction begins; in this process the conduction ceases at or about thepassage of current through zero.

NOTE—Phasecontrolisaparticularcaseofgeneralizedphasecontrol.

161-07-10

161-07-11

161-07-12

delay angleThe phase angle by which the starting instant of current conduction is delayed by phasecontrol.

NOTE— The delay angle can be either constant or variable and is not necessarily intended to be the same forpositive and negative half-cycles.

symmetrical control (single. phase)Control by a device designed to operate in an identical manner on the positive and negativehalf-cycles of an alternating voltage or current.

NOTE— Onthebasisofidenticalpositiveornegativehalf-cyclesoftheinputsource:

— generalized phase control is symmetrical if the current wawefornr is the same for both positive and negativehalf-cycles;

— multicycle control is symmetrical if within each conduction period the number of positive and negative

half-cycles is equal.

asymmetrical control (single phase)Control by a device designed to operate-in a different manner on the positive and negativehalf-cycles of an alternating voltage or current.

NOTES1 Generalizedphasecontrolk asymmetricalif thecurrentwaveform is not the same for both positive andnegative half-cycles.2 Multicycle control is asymmetrical if within each conduction period the number of positive and negativehalf-cycles is unequal.

161-07-13 cycle(MOD 101-14-13) The complete range of states or of values through which a phenomenon or a set of

quantities passes in a given repeatable order.

161-07-14 . cycle of operation(151-03-03) A series of operations that maybe repeated at will or automatically.

161-07-15 point of common couplingPCC (abbreviation)Point of a power supply network, electrically nearest to a particular load, at which otherloads are, or may be, connected.

NOTES

1 These loads can be either devices, equipment or systems, or distinct customer’s installations.

2 In some applications, the term “point of common coupling” is restricted to public networks.

161-07-16

161-07-17

supply system impedanceThe impedance of the supply system as viewed from the point of common coupling.

service connection impedanceThe impedance of the connection from the point of common coupling up to the user’sside of the metering point.

14

IS 1885 (Part 85) :2003IEC 60050 (161) (1990)

161-07-18

161-07-19

161-08-01

161-08-02

161-08-03

161-08-04

161-08-05

161-08-06

161-08-07

161-08-08

161-08-09

161-08-10(604-01-25)

161-08-11(604-03-15)

installation wiring impedanceThe impedance of the wiring between the user’s side of the metering point and a particularoutlet.

apptiance impedanceThe output impedance of an appliance as seen from the end of the flexible cord remotefrom the appliance.

SECTION 161-08- VOLTAGE CHANGES AND FLICKER

voltage changeA variation of the r.m.s. or peak value of a voltage between two consecutive levelssustained for definite but unspecified durations.

NOTE— Whetherthe r.m.s. or peak value is chosen depends upon the application, and which is used shouldbe specified.

relative voltage changeThe ratio of the magnitude of a voltage change to a rated voltage.

duration of a voltage changeInterval of time for the voltage to increase or decrease from the initial value to the finalvalue,

voltage change intervalInterval of time which elapses from the beginning of one voltage change to the beginningof the next voltage change.

voltage fluctuationA series of voltage changes or a continuous variation of the r.m.s. or peak value of thevoltage.

NOTE—Whetherthe r.m.s. or peak value is chosen depends upon the application, and which is used shouldbe specified.

voltage fluctuation waveformTime domain representation of a voltage fluctuation.

magnitude of a voltage fluctuationThe difference between the maximum and minimum values of r.m.s. or peak voltageduring a voltage fluctuation.

rate of occurrence of voltage changesThe number of voltage changes occurring per unit of time.

voltage unbalancevoltage imbalanceIn a polyphase system, a condition in which the r.m.s. values of the phase voltages or thephase angles between consecutive phases are not all equal.

voltage dipA sudden reduction of the voltage at a point in an electrical system followed by voltagerecovery after a short period of time from a few cycles to a few seconds.

voltage surgeA transient voltage wave propagating along a line or a circuit and characterized by arapid increase followed by a slower decrease of the voltage.

15

IS 1885 (Part 85) :2003IEC 60050 (161) (1990)

161-08-12 commutation notchA voltage change, w;th a duration much shorter than the a.c. period, which may appearon an a.c. voltage due to the commutation process in a converter.

161-08-13(845-02-49)

161-08-14(604-01-28)

161-08-15

161-08-16

161-08-17(845-02-50)

161-08-18

161-08-19

161-08-20 -

flickerImpression of unsteadiness of visual sensation induced by a Iight stimulus whoseluminance or spectral distrib~tion fluctuates with time.

flickermeterAn instrument designed to measure any quantity representative of flicker.

threshold of tlicker perceptibilityThe minimum value of a fluctuation of luminance or of spectral distribution which givesrise to a flicker perceptible to a specified sample of the population.

threshold of flicker irritabilityThe maximum value of a fluctuation of luminance or of spectral distribution which givesrise to a flicker tolerated without discomfort by a specified sample of the population.

fusion frequencycritical ticker frequencyFrequency of alternation of stimuli above which flicker is not perceptible, for a given setof conditions.

Short-term flicker indicator (symbol : P,,)A measure of flicker evaluated over a specified time interval of a relatively short duration.

NOTE—The duration is typically 10 minutes, in accordance with [EC 61000-4-15.

long-term flicker indicator (symbol : P,)A measure of flicker evaluated over a specified time interval of a relatively long duration,using successive values of the short-term flicker indicator.

NOTE — The duration is typically 2 hours, using 12 successive values of P,, in accordance with [EC 61000-4-15.

short interruption (of supply voltage)The disappearance of the supply voltage for a time interval whose duration is betweentwo specified limits.

NOTE — A short interruption is considered to be a reduction of the supply voltage to less than 1% of thenominal voltage, with the lower limit of the duration typicaIly a few tenths of a second, and its upper limittypically in the order of one minute (or, h somecasesuptothreeminutes).

I16

IS 1885 (Part 85): 2003IEC 60050 (161) (1990)

INDEX

Aabsorbing clampadjacent channel selectivityalternating componentappliance impedanceartificial handartificial mains networkasymmetrical control (single phase)asymmetrical terminal voltageasymmetrical voltageaverage detector

Bbalunbandwidth (of a device)bandwidth (of an emission or signal)broadband devicebroadband disturbancebroadband emissionburstburst firing control

-ccabinet radiationclamp absorbingclickclick ratecommon coupling, point ofcommon mode conversioncommon mode currentcommon mode impedancecommutation notchcompatibility, electromagneticcompatibility level (electromagnetic)compatibility margin(component), fundamental(component), harmoniccomponent, suppressioncontinuous disturbancecontinuous noisecontrol, asymmetricalcontrol, burst firingcontrol, multicyclecontrol, phasecontrol, symmetricalconversion, common modecoupling factorcoupling pathcritical clicker frequency

161-04-30161-06-17161-02-25161-07-19161-04-27161-04-05161-07-12161-04-12161-04-09161-04-26

161-04-34161-06-09161-06-10161-06-12161-06-11161-06-11161-02-07161-07-07

161-03-05161-04-30161-02-15161-02-16161-07-15161-04-10161-04-39161-04-40161-08-12161-01-07161-03-10161-03-17161-02-17161-02-18161-03-24161-02-11161-02-10161-07-12161-07-07161-07-05161-07-09161-07-11161-04-10161-03-1-8161-03-19161-08-17

crossmodulationcurrent probecyclecycle of operationcyclic on/off switching control

Ddamped oscillatory wavedecoupling factor, mainsdegradation (of performance)delay angledelta networkdesensitizationdetector, averagedetector, peakdetector, quasi-peakdetector, root-mean-squaredifferential mode currentdifferential mode voltagedip, voltagedischarge, electrostaticdiscontinuous interferencediscontinuous disturbancedisturbance, continuousdisturbance, electromagneticdisturbance, impulsivedisturbance, limit ofdisturbance, mains-bornedisturbance, radio (frequency)disturbance field strengthdisturbance powerdisturbance suppressiondisturbance voltagedummy lampduration of a voltage change

Eearth-coupled interferenceearthing inductor

161-06-19161-04-35161-07-13161-07-14161-07-03

161-02-29161-03-04161-01-19161-07-10161-04-06161-06-18161-04-26161-04-25161-04-21161-04-25161-04-38161-04-08161-08-10161-01-22161-02-13161-02-28161-02-11161-01-05161-02-09161-03-08161-03-02161-01-13161-04-0216.1-04-03161-03-22161-04-01161-04-33161-08-03

161-03-20161-03-21

effective radiated power (of any devicein a given direction) 161-04-16

effective selectivity 161-04-17electrical charge time constant (of a

detector) 161-04-18electrical discharge time constant (of a

detector) 161-01-07(electromagnetic) compatibility level 161-03-10(electromagnetic) compatibility margin 161-03-17electromagnetic disturbance 161-01-05

17

IS 1885 (Part 85) :2003-IEC 60050 (161) (1990)

electromagnetic emission 161-01-08electromagnetic environment 161-01-01electromagnetic interference 161-01-06electromagnetic noise 161-01-02(electromagnetic) radiation 161-01-10electromagnetic screen 161-03-26(electromagnetic) susceptibility 161-01-21electrostatic -discharge 161-01-22EMC (abbreviation) 161-01-07EMI (abbreviation) 161-01-06emission, broadband 161-06-11emission (electromagnetic) 161-01-08emission (in radiocommunication) 161-01-09emission, narrowband 161-06-13emission, out-of-band 161-06-02emission, spurious 161-06-01emission level (of a disturbing source) 161-03-11emission level (from a disturbing source) 161-03-12emlsslon margmemission test margingemitter (of electromagnetic disturbance)enclosure, shieldedenvironment, electromagneticenvironment, radioESD (abbreviation)external immunity

Ffactor, couplingfield strength, distrubrancefilter, stopflickerflickermeterfluctuation, voltagefundamental (component)fundamental factorfusion frequency

Ggeneralized phase controlground-coupled interferenceground (reference) planegrounding inductor (USA)

Hhand, artificialharmonic (component)harmonic contentharmonic factor (total)harmonic numberharmonic orderharmonic ratio, nthheating apparatus, radio frequency

161-03-13161-03-14161-01-23161-04-37161-01-01161-01-11161-01-22161-03-07

161-03-18161-04-02161-04-29161-08-13161-08-14161-08-05161-02-17161-02-22161-08-17

161-07-08161-03-20161-04-36161-03-21

161-04-27161-02-18161-02-21161-02-23161-02-19161-02-19161-02-20161-05-02

Iimage rejection ratioimbalance, voltageimmunity, externalimmunity, internalimmunity, mainsimmunity (to a disturbance)immunity levelimmunity limitimmunity marginimmunity test levelimpedance, applianceimpedance, installation wiringimpedance, referenceimpedance, service connectionimpedance, supply systemimpedance, transferimpedance stabilization network, lineimpulseimpulsive disturbanceimpulsive noiseinductor, earthinginductor, groundinginformation technology equipmentinput power controlinstallation wiring impedanceinterference, discontinuousinterference, earth-coupledinterference, electromagneticinterference, ground-coupIedinterference, inter-systeminterference, intra-systeminterference, limit ofinterference, radio frequencyinterference field strength (deprecated

in this sense)interference powerinterference suppressioninterference voltageinterfering signalintermediate-frequency rejection ratiointermodulationinternal immunityinter-system interferenceinterval, voltage changeintra-system interferenceirritability, threshold of flickerISM (qualifier)ISM frequency bandITE (abbreviation)

Llamp, dummylevel (of a time-varying quantity)limit of disturbance

161-06-22161-08-09161-03-0716I-03-06161-03-03161-01-20161-03-14161-03-15161-03-16161-04-41161-07-19161-07-18161-04-04161-07-17161-07-16161-04-14161-04-05161-02-03161-02-09161-02-08161-03-23161-03-21161-05-04161-07-01161-07-18161-02-13161-03-22161-01-06161-03-20161-01-15161-01:16161-03-09161-01-14

161-04-02161-04-03161-03-23161-04-01161-01-04161616161616

-06-21-06-20-03-06-01-15-08-04-01-16

161-08-16161-05-01161-05-03161-05-04

161-04-33161-03-01161-03-08

18

IS 1885 (Part 85) :2003IEC 60050 (161) (1990)

limit of interference

Ime impedance stabilization networkLISN (abbreviation)tong-term flicker indicator

Mmagnitude of a voltage fluctuationmains-borne disturbancemains decoupling factormains immunitymains network, artificialman-made noisemargin, compatibilitymargin, emission testmargin, immunitymargin, immunity testmechanical time constant (of an

indicating instrument)multicycle control (by half-cycles)multicycle control, synchronous

Nnarrowband devicenarrowband disturbancenarrowband emissionnatural noisenoise, continuousnoise, electromagneticnoise, impulsivenoise, man-madenoise, naturalnoise, quasi-impulsivenoise, radio (frequency)noise, randomnotch, commutationnth harmonic ratio

oonloff switching control, cyclicoscillation, parasiticout-of-band emissionoutput power controloverload factor (of a receiver)

Pparasitic oscillationpath, couplingPCC (abbreviation)peak detectorpeak-ripple factorperceptibility, threshold of flickerphase controlphase control, generalizedpoint of common couplingpower, disturbance

161-03-09161-04-05161-04-05161-08-19

161-08-07161-03-02161-03-04161-03-03161-04-05161-01-18161-03-12161-03-13161-03-14161-03-18

161-04-19161-07-05161-07-06

161-06-14161-06-13161-06-13161-01-17161-02-10161-01-02161-02-08161-01-18161-01-17161-02-12161-01-12161-02-14161-08-12161-02-20

161-07-03161-06-08161-06-02161-07-02161-04-20

161-06-08161-03-19161-07-15161-04-24161-02-26161-08-15161-07-09161-07-08161-07-15161-04-03

power, effective radiatedpower control, inputpower control, outputprobe, mu-rentprofessional equipmentprogram (of a control system)protection ratiopulsatingpulsepulse response characteristic (of a

quasi-peak voltmeter)

quarter-wave filter, stopquasi-impulsive noisequasi-peak detectorquasi-peak voltmeter

radiated power, effectiveradiation, cabinet

Q

R

radiation (electromagnetic)(radiation) test siteradio environmentradio (frequency) disturbanceradio (frequency) heating equipmentradio frequency interferenceradio (frequency) noiserandom noiserate of occurrence of voltage changesrate of risereference impedancerejection ratio, imagerejection ratio, intermediate frequencyrejection ratio spurious responserelative voltage changeRFI (abbreviation)ring waveripple contentrise, rate ofrise timer.m.s.-ripple factorroot-mean-square detector

sscreenscreen, electromagneticscreened roomselectivityselectivity, adjacent channelselectivity, effectiveservice connection impedanceseverity level (deprecated)shielded enclosureshort interruption (of supply voltage)

161-04-.16161-07-01161-07-02161-04-35161-05-05161-07-04161-06-05161-02-24161-02-02

161-04-23

161-04-29161-02-12161-04-21161-04-22

161-04-16161-03-05161-01-10161-04-28161-01-11161-01-13161-05-02161-01-14161-01-12161-02-14161-08-08161-02-06161-04-04161-06-22161-06-21161-06-07161-08-02161-01-14161-02-30161-02-25161-02-06161-02-05161-02-27161-04-25

161-03-25161-03-26161-04-37161-06-15161-06-17161-06-16161-07-17161-04-41161-04-37161-08-20

19

IS 1885 (Part 85) :2003IEC 60050 (161) (1990)

short-term flicker indicatorsignal, interferingsignal, undesiredsignal, unwantedsignal-to-disturbance ratiosignal-to-interference ratiosignal-to-noise ratiosingle-signal methodspikespurious emission (of a transmitting

station)spurious response frequencyspurious response .rejection ratiostabilization network, line impedancestop (quarter-wave) filterstriplinesupply system impedancesuppression, disturbancesuppression, interferencesuppression componentsuppressorsurface transfer impedance (of a coaxial

line)surge, voltagesusceptible devicesusceptibility (electromagnetic)switching control, cyclic onloffsymmetrical control (single phase)symmetrical terminal voltagesymmetrical voltagesynchronous multicycle controlsystem impedance, supply

Ttern celltest margin, emissiontest margin, immunitytest site

161-08-18161-01-04161-01-03161-01-03161-06-03161-06-03161-06-04161-06-23161-02-04

161-06-01161-06-06161-06-07161-04-05161-04-29161-04-31161-07-16161-03-22161-03-23161-03-24161-03-24

161-04-15161-08-11161-01-24161-01-21161-07-03161-07-11161-04-11161-04-08161-07-06161-07-16

161-04-32161-03-14161-03-18161-04-28

threshold of flicker irritability 161-08-16threshold of flicker perceptibility 161-08-15time constant, electrical charge 161-04-17time constant, electrical discharge 161-04-18time constant, mechanical 161-04-19(total) harmonic factor 161-02-23transfer impedance (of a screened circuit) 161-04-14transfer impedance, surface (of a coaxial

line)transient (adjective and noun)two-signal method

uunbalance, voltageundesired signalunwanted signal

vV-networkvoltage, asymmetricalvoltage, common modevoltage, differential modevoltage, disturbancevoltage, fluctuationvoltage, symmetricalvoltage changevoltage change, duration of avoltage change, intervalvoltage change, relativevoltage dipvoltage fluctuationvoltage fluctuation waveformvoltage imbalancevoltage surgevoltage unbalancevoltmeter, quasi-peakV-terminal voltage

161-04-15161-02-01161-06-24

161-08-09161-01-03161-01-03

61-04-0761-04-0961-04:0961-04-0861-04-0161-08-05

161-04-08161-08-01161-08-03161-08-04161-08-02161-08-10161-08-05161-08-0616I-08-09161-08-11161-08-09161-04-22161-04-13

20

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should ascertain that they are in possession of the latest amendments or edition by referring to the latest issue of‘131SCatalogue’ and ‘Standards: Monthly Additions’.

This Indian Standard has been developed from Doc : No. LTD22(1813).

Amendments Issued Since Publication

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