OVERVIEW OFEMI/EMC

WHAT IS EMI/EMC An Electromagnetic disturbance which may

degrade the performance of an equipment or device or cause malfunction of the equipment is called electromagnetic interference.

Electromagnetic Compatibility is a near perfect state in which a receptor (device or system) functions are satisfactorily in common electromagnetic environment without introducing intolerable electromagnetic disturbance to any other device/ equipment/system in that environment.

IMPORTANCE OF EMC

EMC is becoming more important because there are so many opportunities today for EMC issues.

Increased use of electronic devices. Automotive Application. Personal computing/Entertainment/Communication. Increased potential for Susceptibility/Emission. Lower Supply Voltage. Increasing Clock Frequencies. Increasing Packaging Density. Demand for smaller, lighter, cheaper, lower price

shop.

BASIC ELEMENTS OF EMI SITUATIONS

Interference occurs if the received energy causes the receptor to function in unwanted manner.

Whether the receiver is functioning in wanted or unwanted manner, depends upon the coupling path as well as the source and victim.

The coupling path is to be made as inefficient as possible.

CAUSES OF EMI/EMC SOURCES Refrigerators, washing machine, electric motors. Arc welding machine. Electric shavers, AC, Computers. Fast switching digital devices, ICs etc Power chords of computers, UPS etc. Aircraft navigation and Military equipments. VICTIMS Communication Receivers. Microprocessors, Computers. Industrial Controls. Medical Devices. Household Appliances. Living Beings.

EFFECTS OF EMI Momentary disturbances in T.V and Radio reception

due to operation mixer-grinder, Electric shavers, Passing vehicles.

Reset of computers and loss of data. Burn of sensitive cells an components. Change of setting of status of control equipments. Failure of Pace-maker implanted in a patient due to a

“walkie-talkie”. False initiation electro explosive detonators. Malfunctioning of flight controlling system due to use

of laptop by passengers. Biological hazards.

PURPOSE AND METHODOLOGY FOR EMC SYSTEM A SYSTEM IS SAID TO BE ELECTROMAGNETICALLY

COMPATIBLE: It doesn’t cause interference with other systems. It is not susceptible to emissions from other

system. It doesn’t cause interference with itself. THE METHODOLOGIES TO PREVENT EMI ARE: Suppress the emission at the source point, best

method to control EMI. Make the coupling path as inefficient as possible. Make the receiver less susceptible to emission.

STANDARDS SETTING INSTITUTIONS

DOD- Department of Defence (USA)-Immunity and Emission MIL Standard.

IEC- International Electrotechnical Commission (EU)-Immunity Standard.

CISPR- International Special Committee On Radio Interference operating under IEC-Emission Standard.

FCC- Federal Communication Commission(EU)-Emission Standard.

BSI- British Standard Institution(UK)-Emission Standard.

VDE- Verband Deutscher Electrotechniker(Germany)-Emission Standard.

EMI/EMC SPECIFICATIONS

Commercial Specifications

Military Specifications

MIL-STDs

Planning and project management of EMC. Test methods and specific test equipment Specified limits which must be met Specification for acceptable EMI measurement

receivers

Emission TestsTest Type Frequency

rangeMethod

CE 101 Conducted emissions on power leads

30Hz to 10kHz Differential mode, current probe and LISN

CE 102 Conducted emissions on power leads

10kHz to 10MHz

Voltage measurement on LISN port, each power lead

CE 106 Conducted emissions, antenna terminal

10kHz to 40GHz depending on EUT operation

Direct connection or via coupler, to antenna port

RE 101 Magnetic field radiated emissions

30Hz to 100kHz Search coil 70mm from each EUT face and connector

Emission Tests

RE 102 Electric field radiated emissions

10kHz to 18GHz

Various antennas, 1m from EUT; screened room preferred

RE103 Radiated emissions – antenna spurious and harmonic outputs

10kHz to 40GHz depending on EUT operation

Alternative to CE 106 for transmitters with integral antennas

MIL-STD-461E Susceptibility tests

Test Description To test immunity Method

CS 101 Power leads, 30 Hz to 150kHz

Ripple on power supply

Coupling transformer in series with power line

CS 103 Antenna port, inter modulation, 15kHz to 10GHz

Presence of inter modulation products

Determined on a case-by-case basis

CS 104 Antenna port, undesired signal rejection, 30Hz to 20GHz

Presence of spurious responses

Determined on a case-by-case basis

CS 105 Antenna port, cross modulation, 30Hz to 20GHz

Presence of cross-modulation products

Determined on a case-by-case basis

CS 109 Structure current, 60Hz to 100kHz

Currents flowing in the EUT structure

Currents injected by transformer at diagonal extremes across surfaces

MIL-STD-461E Susceptibility testsCS 114 Bulk cable injection, 10kHz to 200MHz RF signals coupled onto EUT

associated cabling Pre-calibrated current injected by

current probe onto each cable bundle, including power leads with returns and grounds exclude

CS 115 Bulk cable injection, impulse excitation Impulse signals coupled onto EUT associated cabling

As CS 114, but with impulse generator giving 30ns pulses at 30Hz repetition rate

CS 116 Damped sinusoidal transients, cables and power leads, 10kHz to 100MHz

Damped sinusoidal transients due to excitation of wiring, coupled onto cables and power leads

As CS 114, but with damped sinewave generator giving pulses at least once per second at a minimum of 0.01, 0.1.1, 10, 30, and 100MHz30ns pulses at 30Hz repetition rate

RS 101 Magnetic field 30Hz to 100kHz Magnetic field from e.g. transformers and power cables

Calibrated radiating loop, 5cm from EUT face, or place EUT within calibrated Helmholtz coils

RS 103 Electric Field 2MHz to 40GHz Transmitted fields Anechoic screened room, E-field sensor monitoring field during test, transmit antenna 1m from boundary of EUT, or alternative method using mode stirred reverberation chamber

RS 105 Transient electromagnetic field Unidirectional pulsed radiated field 2.3/23ns 50kV/m

Transient pulse generator feeding TEM cell, parallel plate transmission line or similar

Commercial Specifications

International Specifications ISO IEC

National Specifications BIS,EN,BSI,FCC etc

User Specifications PGCIL, RDSO,TEC

Basis of Existing Specifications

RFI: intended to protect a radio spectrum from specific interference sources, such as information technology equipment, motor vehicle ignition, household appliances or fluorescent lights.

Mains emissions : specifically harmonic currents and short term variations, to protect a low voltage power distribution network.

Product and Industry specific : To ensure the immunity from interference of particular types of product, such as process instrumentation or legal metrology, or to regulate emissions from equipment that will be used in a specific environment, such as marine equipments.

Types of Specifications

Basic Standards - Basis for performing the test - IEC & CISPR Generic Standards - Developed for industry use for products which does not have product std -IEC 61000-6-1,2,3,4 Product Family Standards -Developed for specific product/family

certification - CISPR 22,24

IEC Publications IEC 61000-1 Part 1 General

General consideration (introduction, fundamental principles, functional safety) Definitions, terminology.

IEC 61000-2 Part 2: EnvironmentDescription of the environment Classification of the

environment Compatibility levels.IEC 61000-3 Part 3: Limits

Emission limitsImmunity limits

IEC 61000-4 Part 4: Testing and measurement techniquesMeasurement techniques Testing techniques

IEC 61000-5 Part 5: Installation and mitigation guidelinesInstallation guidelinesMitigation methods and devices

IEC 61000-6 Part 6: Generic standards

Basic Specifications IEC 61000-4-2 Electrostatic dischargeIEC 61000-4-3 Radiated radio frequency electromagnetic field

testIEC 61000-4-4 Electrical fast transient/ burst immunity test IEC 61000-4-5 Surge immunity test IEC 61000-4-6 Immunity to conducted disturbances induced by

radio frequency fieldsIEC 61000-4-7 General guide on harmonics and measurements

and instrumentation, for power supply systems and equipment connected thereto

IEC 61000-4-8 Power frequency magnetic immunity field testIEC 61000-4-9 Pulse magnetic immunity testIEC 61000-4-10 Damped oscillatory magnetic field immunity test

Basic SpecificationsIEC61000-4-11 Voltage dip, short interruptions and voltage variations immunity

testIEC61000-4-12 Oscillatory waves immunity test (to become Ring wave

immunity, with damped oscillatory wave test to part 18)IEC61000-4-13 Harmonics, inter harmonics including main signaling at AC port,

low frequency immunity testIEC61000-4-14 Voltage fluctuation immunity test

IEC61000-4-15 Flicker meter functional and design specificationsIEC61000-4-16 Test for immunity to conducted, common mode disturbances in

the frequency range 0 Hz to 150kHzIEC61000-4-17 Ripple on DC input power port immunity test

IEC61000-4-18 Oscillatory waves immunity test (new edition)

IEC61000-4-19 Emission and immunity testing in transverse electromagnetic (TEM) wave guides

IEC61000-4-20 Reverberation chamber test methods

Basic SpecificationsIEC 61000-4-21 Radiated emissions and immunity measurements in fully anechoic rooms (FARs)

IEC 61000-4-22 Test methods for protective devices for HEMP and other radiated disturbancesIEC 61000-4-23 Test methods for proactive devices for hemp conducted disturbance

IEC 61000-4-24 HEMP immunity test methods for equipment and systemsIEC 61000-4-25 Unbalance immunity test

IEC 61000-4-26 Variation of power frequency immunity testIEC 61000-4-27 Voltage dips, short interruptions and voltage variations on DC input power port

immunity tests IEC 61000-4-28 Power quality measurement methods

IEC 61000-4-29 Measurements in the frequency range 2kHz to 9kHzIEC 61000-4-30 High-altitude electromagnetic pulse (HEMP) simulator compendiumIEC 61000-4-31 Measurement methods for high-power transient parametersIEC 61000-4-32 Voltage dips, short interruptions and voltage variation immunity test for

equipment with input current more than 16A per phaseIEC 61000-4-33 Intentional Electromagnetic Interference (EMI) Simulator Compendium

Product Family StandardsSpecificationSpecification Title Title CISPR 11CISPR 11 Limits & Methods of measurements of Radio Limits & Methods of measurements of Radio

Dist. Of ISMDist. Of ISMCISPR 12CISPR 12 Limit & methods of Measurement of vehicles Limit & methods of Measurement of vehicles

CISPR 13CISPR 13 Limit & methods of Measurement of Broad cast Limit & methods of Measurement of Broad cast & TV receiver & TV receiver

CISPR 14-1CISPR 14-1 Limit & methods of Measurement of Domestic Limit & methods of Measurement of Domestic AppliancesAppliances

CISPR 14-2CISPR 14-2 Immunity requirement of Domestic AppliancesImmunity requirement of Domestic Appliances

CISPR 15CISPR 15 Limit & methods of Measurement of Luminaries Limit & methods of Measurement of Luminaries & Lighting Eqpt& Lighting Eqpt

CISPR 22CISPR 22 Limit & methods of Measurement of ITE Limit & methods of Measurement of ITE EquipmentEquipment

CISPR 24CISPR 24 Immunity requirement of ITE ProductsImmunity requirement of ITE Products

Product Family Standards

SpecificationSpecification Title Title

CISPR 20 CISPR 20 Immunity Requirement of Broadcast & TV Immunity Requirement of Broadcast & TV receiversreceivers

CISPR 25CISPR 25 Limits & method of Measurement of Limits & method of Measurement of automotive automotive

IEC 61000-3-2IEC 61000-3-2 Limit & methods of Harmonic Current Limit & methods of Harmonic Current EmissionsEmissions

IEC 61000-3-3IEC 61000-3-3 Limit & methods of Voltage Fluctuations & Limit & methods of Voltage Fluctuations & Flicker in low voltage supply system Flicker in low voltage supply system

Product Application Environment

Class A Limit Industrial, Scientific & Medical

Environment • Class B Limit Domestic application Portable Equipment Telecom Terminal equipment Personal Computer

Conducted Emission Limit

Class A Limit Class A Limit Class B Limit Class B Limit FreqFreq Emission Limit Emission Limit Freq.Freq. Emission LimitEmission Limit

MHz MHz dBuVdBuV(QP)(QP)

dBuVdBuV(Avg)(Avg)

MHz MHz dBuVdBuV(QP)(QP)

dBuVdBuV(Avg)(Avg)

0.150-0.50.150-0.5 7979 6666 0.150-0.50.150-0.5 66-5666-56 56-4656-46

0.5-50.5-5 7373 6060 0.5-50.5-5 5656 4646

5-305-30 7373 6060 5-305-30 6060 5050

Radiated Emission Limit

Class A Limit Class A Limit Class B Limit Class B Limit Measurement Distance : 30 mMeasurement Distance : 30 m Measurement Distance : 10 mMeasurement Distance : 10 m

FreqFreq Emission Limit Emission Limit FreqFreq Emission Limit Emission Limit

MHz MHz dBuV/m (Q.P)dBuV/m (Q.P) MHz MHz dBuV/m (Q.P)dBuV/m (Q.P)

30-23030-230 3030 30-23030-230 3030

230-1000230-1000 3737 230-1000230-1000 3737

Radiated Emission Limits

EQUIPMENT & EMC ENVIRONMENT

EMISSION PARAMETERS

Conducted Emission Power Line Emission Signal line Emission

Radiated Emission E & H, EM Radiation Current Harmonic Emission Flicker

CONDUCTED EMISSION TEST SETUP

OPEN AREA TEST SITE

RADIATED EMISSION AND SUSCEPTIBILITY

Radiated Emission In Anechoic Chamber

Radiated Immunity Test Set up

RADIATED IMMUNITY TESTING OF AN EQUIPMENT

G-TEM CELL

RF Conducted Immunity Test

Bulk Current Method

Harmonic & Flicker Measurement

ESD Current Wave

Electrostatic Discharge Test

Electric Fast Transient Test

Surge Waveforms

Power Frequency Mag. Field Test

Damped oscillatory magnetic fieldimmunity test

Voltage Dip & Interruption Test

SOME EMI SUPRESSION COMPONENTS

THANK YOU

PANKAJ RANGRAB.TECH (E.C.E)80506108026