test and measurement for emc - west michigan and measurement for emc... · test and measurement for...

Test and Measurement for EMCBogdan Adamczyk, Ph.D., iN.C.E.

Professor of EngineeringDirector of the Electromagnetic Compatibility Center

Grand Valley State University, Michigan, USA

Ottawa, Canada

July 25-29, 20162016 IEEE EMC Symposium (MO-PM-1) 1

2016 IEEE EMC Symposium (MO-PM-1) 2

Test and Measurement for EMC - Overview

Description of basic setups for radiated and conducted emissions,

radiated and conducted immunity, and electrostatic discharge (ESD).

A representative sample of the commercial EMC regulations will be used

to explain the basics of the EMC measurements.

This presentation is not intended to review all existing EMC regulations or

discuss the details of each test procedure and the required documentation.

Pictures of the typical test setups, equipment and facility will be presented.

Each test and the equipment required to perform it will be discussed to the

extent needed to gain the basic understanding of and interpret the test

results.

Each test will be supported by the examples of the real test data, many

of them illustrating the “pass” and “fail” results.


Basic EMC Tests – Presentation Outline

3. Radiated Emissions (RE) – FCC/CISPR 22, CISPR 25

1. Introduction - FCC Part 15 and CISPR 22 Standards

2. Conducted Emissions (CE) – FCC/CISPR 22, CISPR 25

5. Radiated Immunity (RI) – ISO 11452-2, ISO 11452-11, IEC 61000-4-21

4. Conducted Immunity (CI) – ISO 11452-4

6. Electrostatic Discharge (ESD) – ISO 10605, IEC 61000-4-2


The most widely outside the United States is CISPR 22 that sets limits on the radiated and

conducted emissions of information technology equipment, which basically includes all digital

devices in the similar meaning as for the FCC.

CISPR - Comité International Spécial des Perturbations Radioélectriques

(International Special Committee on Radio Interference)

The limits are divided into Class A (commercial devices) and Class B equipment (residential

devices) and their meaning is essentially the same as the FCC definitions.

FCC and CISPR Standards

EMC standards and regulations have been imposed by various government regulatory bodies

and various industries to control allowable emissions from electronic products.

In the United States the Federal Communications Commission (FCC) regulates

the use of radio and wire communications.

Part 15 of the FCC Rules and Regulations sets forth technical standards and

operational requirements for radio-frequency devices.


Peak vs. Quasi-Peak vs. Average

As the repetition rate increases, the quasi-peak detector produces a higher voltage output

(response on spectrum analyzer or EMI receiver).

Most radiated and conducted limits in EMC testing are based on quasi-peak detection mode.

Quasi-peak detectors weigh signals according to their repetition rate, which is a way of measuring

their “annoyance factor”.

High amplitude low repetition rate signals could produce the same output as low amplitude high

repetition rate signal.

Because quasi-peak readings are much slower, (by 2 or 3 orders of magnitude compared with

peak) it is very common to scan initially with the peak detection first, and then if this is marginal or

fails, switch and run the quasi- peak measurement against the limits.

Peak vs. Quasi-Peak vs. Average

Quasi-peak detector readings will be less

than or equal to the peak detection.

Average detector will be less than or

equal to the quasi-peak detection.

EMI receiver


72016 IEEE EMC Symposium (MO-PM-1)

Current Probe Measurements

Peak Measurement



Average Measurement



Quasi - Peak Measurement

FCC and CISPR 22 Conducted Emissions Limits

Class A Class B


Class B (measured at 3 m)

FCC Radiated Emissions Limits

Class A (measured at 10 m)


CISPR 22 vs. FCC Radiated Emissions Limits

CISPR 22 Class B (measured at 10 m)

CISPR 22 Class A (measured at 10 m)

FCC Class A (measured at 10 m)

FCC Class A (measured at 10 m)

CISPR 22 Class A and B (measured at 10 m)


Conducted Emissions



Conducted EmissionsConducted emissions are the noise currents generated by the DUT (EUT) that propagate through

the power cord or harness to other components/systems or power grid.

FCC/CISPR 22 set the limits on the ac conducted emissions.

CISPR 25 (automotive standard), MIL-STD-461 (military standard) set the limits on the dc

conducted emissions.

To measure the conducted emissions an Artificial Network (AN) or the Line Impedance

Stabilization Network (LISN) is used. (LISN looks like a 50 Ω resistor to the EUT and basically

acts as an LC low pass filter).

EMI Receiver

EUT

15

AC and DC LISNs

AC LISN

DC LISN DC LISN


Conducted Emissions Measurements

FCC and CISPR 22 require two conducting

planes (horizontal and vertical)

and use the voltage method to measure the

conducted emissions

CISPR 25 requires a screen room and

specifies two methods:

- Voltage method

- Current probe method


FCC/CISPR 22 – Conducted Emissions (Voltage Method)


FCC/CISPR 22 – Conducted Emissions (Voltage Method)

2016 IEEE EMC Symposium (MO-PM-1)18

FCC/CISPR 22 Conducted EmissionsLine 150kHz – 2 MHz

Line 2 MHz – 30 MHz


Class B

FCC/CISPR 22 Conducted Emissions

Neutral 150kHz – 2 MHz

Neutral 2 MHz – 30 MHz


Class B


CISPR 25 Voltage Method - Conducted Emissions

Service

/Band

Frequency

MHz

Levels (dBµV)

Class 1 Class 2 Class 3 Class 4 Class 5

PK QP PK QP PK QP PK QP PK QP

LW 0.15 - 0.3 110 97 100 87 90 77 80 67 70 57

MW 0.53 - 1.8 86 73 78 65 70 57 62 49 54 41

SW 5.9 – 6.2 77 64 71 58 65 52 59 46 53 40

FM 76 - 108 62 49 56 43 50 37 44 31 38 25

TV Band 1 41 - 88 58 - 52 - 46 - 40 - 34 -

CB 26 - 28 68 55 62 49 56 43 50 37 44 31

VHF 30 - 54 68 55 62 49 56 43 50 37 44 31

VHF 68 - 87 62 49 56 43 50 37 44 31 38 25

Service

/Band

Frequency

MHz

Levels (dBµV)


AVG AVG AVG AVG AVG

LW 0.15 - 0.3 90 80 70 60 50

MW 0.53 - 1.8 66 58 50 42 34

SW 5.9 – 6.2 57 51 45 39 33

FM 76 - 108 42 36 30 24 18

TV Band 1 41 - 88 48 42 36 30 24

CB 26 - 28 48 42 36 30 24

VHF 30 - 54 48 42 36 30 24

VHF 68 - 87 42 36 30 24 18



22


CISPR 25 Current Probe Method - Conducted Emissions

Service

/Band

Frequency

MHz

Levels (dBµA)


AVG AVG AVG AVG AVG

LW 0.15 - 0.3 70 60 50 40 30

MW 0.53 - 1.8 38 30 22 14 6

SW 5.9 – 6.2 23 17 11 5 -1

FM 76 - 108 8 2 -4 -10 -16

TV Band 1 41 - 88 14 8 2 -4 -10

CB 26 - 28 14 8 2 -4 -10

VHF 30 - 54 14 8 2 -4 -10

VHF 68 - 87 8 2 -4 -10 -16

Service

/Band

Frequency

MHz

Levels (dBµA)


PK QP PK QP PK QP PK QP PK QP

LW 0.15 - 0.3 90 77 80 67 70 57 60 47 50 37

MW 0.53 - 1.8 58 45 50 37 42 29 34 21 26 13

SW 5.9 – 6.2 43 30 37 24 31 18 25 12 19 6

FM 76 - 108 28 15 22 9 16 3 10 -3 4 -9

TV Band 1 41 - 88 24 - 18 - 12 - 6 - 0 -

CB 26 - 28 34 21 28 15 22 9 16 3 10 -3

VHF 30 - 54 34 21 28 15 22 9 16 3 10 -3

VHF 68 - 87 28 15 22 9 16 3 10 -3 4 -9



26

Radiated Emissions



Radiated Emissions

Open Area Test Site (OATS) – CISPR 22

Semi-Anechoic Chamber – CISPR 25

EMC standards specify that that the measurement of emissions from products be

performed in the OATS (Open Area Test Site) or in the semi-anechoic test chamber.


Open Area Test Site (OATS)

The ideal OATS is a flat piece of land, free of overhead wires and nearby reflective structures,

away from any and all external signals, with a perfectly reflective ground plane.

Since the OATS should be away from all reflective structures, this requires the control room to be

remotely located or located underneath the ground plane.

The measurements should be made with a quasi-peak measuring receiver in the frequency range

30 MHz to 1GHz (peak measurements are permitted).

Weather protection is usually needed, but the structure should not contain any metallic material

(beams, nails, door hinges, etc.).


Open Area Test Site (OATS)

The test site should be sufficiently large to permit antenna placing at the specified distance.

The boundary of the area is defined by an ellipse.

Ground plane should extend at least 1 m beyond the periphery of EUT and the largest measuring

antenna, and cover the entire area between the EUT and the antenna.


Open Area Test Site (OATS) Measurements

Ambient measurement

DUT emissions measurement

CISPR 25 - Radiated Emissions

Semi anechoic chamber

(not CISPR 25 chamber)


Power

supply

LISN

Test

harness

Simulation and

Monitoring System

EUT

Styrofoam

(low 𝜖𝑟)

Load

simulator

Ground

planeGround

plane

bonded to

shielded

enclosure

Shielded

enclosure

Measuring

instrument

Rod antenna

with counterpoise

1000 ± 10

1000 𝑚𝑖𝑛

100 ± 10

200 ± 101000 𝑚𝑖𝑛

Grounding

connection

(full width)1500±

75

RF absorber

Dimensions in mm – not to scale

CISPR 25 - Radiated Emissions – Monopole Antenna


35

900 ± 100

EUT

Front view

ℎ + +10/−20

50±5

Load

simulator

Styrofoam

(low 𝜖𝑟)

Side view

1m vertical monopole 0.15 MHz – 30 MHz

Antenna

matching

unit

CISPR 25 - Radiated Emissions – Monopole Antenna



CISPR 25 – Monopole Antenna Measurements

Power

supply

LISN

Test

harness

EUT

Styrofoam

(low 𝜖𝑟)

Load

simulator

Ground

planeGround

plane

bonded to

shielded

enclosure

Shielded

enclosure1000 ± 10

100 ± 10

200 ± 101000 𝑚𝑖𝑛

1500±

75


1000 𝑚𝑖𝑛

Biconical

antenna

Simulation and

Monitoring System

Measuring

instrument

RF absorber

CISPR 25 - Radiated Emissions – Biconical Antenna


38

900 ± 100

EUT

Front view

50±5Load

simulator

Styrofoam

(low 𝜖𝑟)

Side view

≥250

100±10

Biconical antenna 30 MHz – 300 MHz

CISPR 25 - Radiated Emissions – Biconical Antenna



CISPR 25 – Biconical Antenna Measurements

Power

supply

LISN

Test

harness

EUT

Styrofoam

(low 𝜖𝑟)

Load

simulator

Ground

planeGround

plane

bonded to

shielded

enclosure

Shielded

enclosure1000 ± 10

100 ± 10

200 ± 101000 𝑚𝑖𝑛

1500±

75


1000 𝑚𝑖𝑛

Log-periodic

antenna

Simulation and

Monitoring System

Measuring

instrument

RF absorber

CISPR 25 - Radiated Emissions – Log-Periodic Antenna


900 ± 100

EUT

Front view

50±5Load

simulator

Styrofoam

(low 𝜖𝑟)

Side view

≥250

100±10

Log-periodic antenna 300 MHz – 1000 MHz

CISPR 25 - Radiated Emissions – Log-Periodic Antenna



CISPR 25 – Log-Periodic Antenna Measurements

Conducted Immunity



Conducted Immunity ISO 11452-4

Bulk Current Injection (BCI) is a method of carrying out immunity tests by inducing disturbance

signals directly into the wiring harness by means of a current injection probe.

Two BCI tests methods are specified:

- Substitution Method

- Closed-Loop Method with Power Limitation

The injection probe is a current transformer

through which the wiring harness of the device

under test (DUT) is passed.

Immunity tests are carried out by varying the

test severity level and frequency (1 MHz – 400

MHz) of the induced disturbance.

Signal Generator

(connected to the

power amplifier)

Screen Room

Directional Coupler

(connected to power

meters)

Power Meters

(measure forward and reverse power)

Power Amplifier



Signal Generator

Directional Coupler

Power Meters

Power Amplifier

Power Sensors




Ground Plane

Current Injection Probe Current Measuring Probe

LISNs

Battery

Styrofoam

Wiring Harness

DUTCalibration fixture


Ground

plane

EUT

Styrofoam

(low 𝜖𝑟)

Current

injection probe

Load

simulator

LISN

Power

supply

Simulation and

Monitoring System

Shielded

enclosure

Table

top

Ground plane

bonded to shielded

enclosure

≥200

≥100

≥500

Wiring

harness

Directional

coupler

Power

meter

Power

meter

Power

amplifier Signal

generator

Com

pu

ter

Mo

nito

r

Camera

Fiber optic link

Conducted Immunity – Substitution Method ISO 11452-4

In the substitution method a calibration fixture is used to record power needed to produce required

current in the 50 Ω. Then during the testing that power is applied over the frequency range.


900 ± 100

EUT

50±5Load

simulator

Styrofoam

(low 𝜖𝑟)

2000 𝑚𝑖𝑛

1700( +300 −0)

Front view Side view

1000 𝑚𝑖𝑛150 ± 50

750 ± 50

450 ± 50

Injection probe is placed in three different locations.



Ground

plane

EUT

Current injection

probe

Load

simulator

LISN

Power

supply

Shielded

enclosure

Table

top

Ground plane

bonded to shielded

enclosure

≥200

≥100

≥500

Wiring

harness

Current measurement

probe

Spectrum

analyzer

Camera

Simulation and

Monitoring System

Directional

coupler

Power

meter

Power

meter

Power

amplifier Signal

generator

Com

pu

ter

Monitor

Fiber optic link

Conducted Immunity – Closed-Loop Method with Power Limitations ISO 11452-4

In this method a calibration fixture is used to record power needed to produce required current in

the 50 Ω environment. Then during the testing power is applied until the required current is

measured or the power limit is reached (Plimit = 4 X Pcalibration).


51

900 ± 100

EUT

50±5Load

simulator

Styrofoam

(low 𝜖𝑟)

1500 𝑚𝑖𝑛

1000( +200 −0)

Front view Side view

1000 𝑚𝑖𝑛

50 ± 10

900 ± 10

Injection probe is placed 900 mm form the DUT.

Measurement probe is placed 50 mm for the DUT.

Conducted Immunity – Closed-Loop Method with Power Limitations ISO 11452-4




Frequency bandMHz

Test level ImA

Test level IImA

Test level IIImA

Test level IVmA

Test level VmA

1 - 3 60 x f(MHz)/3 100 x f(MHz)/3 150 x f(MHz)/3 200 x f(MHz)/3 Specific values agreed between the users of this

part of ISO 11452

3 - 200 60 100 150 200

200 - 400 60 x 200/ f(MHz)

100 x 200/ f(MHz)

150 x 200/ f(MHz)

200 x 200/ f(MHz)

Test Severity Levels (BCI)

Level 1

Level 4



Failures

Level 1

Level 4



Pass

Radiated Immunity



Radiated Immunity

Reverberation Chamber – ISO 11452-11

Semi-Anechoic Chamber – ISO 11452-2

Horizontal

tuner/stirrer

Motor

Receiving

antenna

Transmitting

antenna

Volume of

uniform field

𝑚𝑖𝑛 𝜆 4𝑚𝑖𝑛 𝜆 4

𝑚𝑖𝑛

𝜆4

𝑚𝑖𝑛

𝜆4

Shielded

enclosure

Attenuator

Directional

coupler

Power

meter

Power

meter

Power

amplifier

Signal

generator

Motor

controller

Spectrum

analyzer

EU

T

Table

E–field

probe

E–field

Probe monitor

Co

mp

ute

rM

on

ito

r

Camera

Fiber optic link

ISO 11452-11 Radiated Immunity – Reverberation Chamber


58


ISO 11452-11 Radiated Immunity – Reverberation Chamber

Power amplifier

Power meter

Signal generator

E-field probe

monitor


Radiated Immunity – Reverberation Chamber

Reverberation chamber is a shielded highly

conductive enclosure.

Reverberation chamber dimensions should be large

compared to the wavelength.

Mechanical tuner/stirrer:

Should have one dimension that is at least one –

quarter wavelength at the lowest frequency.

Should be also as large as possible

with respect to the overall chamber

size in that one dimension and should

be at least three-quarters of the

smallest chamber dimension.

Should be shaped asymmetrically (so

a non-repetitive pattern is obtained

over one revolution).

Power

supplyLISN

EUT

Styrofoam

(low 𝜖𝑟)

Load

simulator

Ground

plane

Ground plane bonded

to shielded enclosure

Shielded

enclosure

1000 ± 10

100 ± 10

200 ± 10

≥ 1000

1500±

75

RF absorber


≥ 500

ISO 11452-2 - Radiated Immunity – Biconical Antenna

≥ 1500

≥ 2000

Biconical

antenna

Simulation and

Monitoring System

Directional

coupler

Power

meter

Power

meter

Power

amplifier Signal

generator

Com

pu

ter

Monitor

Fiber optic link

Camera


61

Power

supplyLISN

EUT

Styrofoam

(low 𝜖𝑟)

Load

simulator

Ground

plane

Ground plane bonded

to shielded enclosure

Shielded

enclosure

1000 ± 10

100 ± 10

200 ± 10

≥ 1000

1500±

75

RF absorber


≥ 500

≥ 1500

≥ 2000

Simulation and

Monitoring System

Directional

coupler

Power

meter

Power

meter

Power

amplifier Signal

generator

Com

pu

ter

Monitor

Fiber optic link

Camera

Log-periodic

antenna

ISO 11452-2 - Radiated Immunity – Log-Periodic Antenna


62

ISO 11452-2 - Radiated Immunity - Fail


ISO 11452-2 - Radiated Immunity - Pass


Electrostatic Discharge




IEC 61000-4-2 – Testing and measurement techniques – Electrostatic discharge immunity test

Air discharge method – a method of testing, in which the charged electrode of the test

generator is brought close to the EUT, and the discharge actuated by a spark to the EUT.

Contact discharge method – a method of testing, in which the electrode of the test

generator is held in contact with the EUT, and the discharge actuated by the discharge

switch within the generator.

ISO 10605 – Road Vehicles – Test methods for electrical disturbances from electrostatic discharge

Direct application – application of the discharge directly to the EUT.

Indirect application – application of the discharge to a coupling plane in the vicinity of the

EUT.


Human Body Model for ESD

pFCHB 50 absolute capacitance of the human body

Because of the proximity of other objects, in addition to

the absolute capacitance, an additional capacitance

must be taken into account when determining the total

capacitance of an object.

To create the human body model for ESD, we start with

the absolute capacitance of 50 pF.

Thus, the human body capacitance can vary from about 50 pF to about 250 pF.

In addition to this capacitance we have an additional

capacitance between each foot and ground; 50 pF per

foot (total of 100 pF).

Because of the presence of the adjacent objects, an

additional capacitance of 50 to 100 pF may also exist.


Human Body Model for ESD

Human Body Circuit Model

Human body model simulates the ESD event when a charged body directly transfers

an electrostatic charge to the ESD sensitive device.

Typical R and C combinations:

pFCR

pFCR

pFCR

pFCR

330,2000

150,2000

330,330

150,330

ESD Gun

RC Cartridge


ESD Gun Cartridge

330 pF

2 kΩ



ISO 10605 - ESD generator parameters

Parameter Characteristic

Output voltage range contact discharge mode 2 kV to 15 kV

Output voltage range air discharge mode 2 kV to 25 kV

Output polarity Positive and negative

Storage capacitances 150 pF, 330 pF

Storage resistance 330 Ω, 2000 Ω

IEC 61000-4-2 Test Levels and ESD generator parameters

Contact discharge Air discharge

Level Test voltage (kV) Level Test voltage (kV)

1 2 1 2

2 4 2 4

3 6 3 8

4 8 4 15

Storage capacitance Storage resistance

150 pF 330 Ω



The testing shall be performed by direct and indirect application of discharges to the EUT according to a

test plan. This should include:

1. Representative operating conditions of the EUT;

2. Whether the EUT should be tested as table-top or floor-standing;

3. The points at which discharges are to be applied;

4. At each point, whether contact or air discharges are to be applied;

5. The test level to be applied;

6. The number of discharges to be applied at each point for compliance testing;

The test results shall be classified on the basis of the operating conditions and the functional

specifications of the EUT, as in the following, unless different specifications are given by the product

committees or product specifications:

1. Normal performance within the specification limits;

2. Temporary degradation or loss of function or performance which is self-recoverable;

3. Temporary degradation or loss of function or performance which requires operator intervention or

system reset;

4. Degradation or loss of function which is not recoverable due to damage to equipment (components)

or software, or loss of data.

IEC 61000-4-2 – Testing and measurement techniques – Electrostatic discharge immunity test

Battery (ISO 10605)Vertical Ground Plane (IEC 61000-4-2)


72

Ground plane

+ _

Battery

Ground point (connected to facility ground)

DUT

Dissipative

mat

HCP

(Horizontal

Coupling

Plane

1.6 x 0.8 m)

ESD Gun

Power Generator

AC Power

Styrofoam

(low 𝜖𝑟)

Periphery

DUT remotely

accessible parts

ESD gun

470 kΩ

resistors

Nonconductive

table (80 cm

above ground)

ISO 10605 – Powered DUT – Direct ESD


Ground plane

+ _

Battery

DUT

Dissipative

mat

HCP

(Horizontal

Coupling

Plane,

1.6 x 0.8 m)

Nonconductive

table (80 cm

above ground)

ESD Gun

Power Generator

AC Power

Styrofoam

(low 𝜖𝑟)

Periphery

DUT remotely

accessible parts

ESD gun


470 kΩ

resistors

ISO 10605 – Powered DUT – Indirect ESD


DUT

HCP

(Horizontal

Coupling

Plane

1.6 x 0.8 m)

Nonconductive

table (80 cm

above ground)

ESD Gun

Power Generator

AC Power

ESD gun


Dissipative

mat

ISO 10605 – Packaging and Handling


Ground plane

Insulation

HCP

(Horizontal

Coupling

Plane

1.6 x 0.8 m)

ESD Gun

Power Generator

AC Power

ESD gun

470 kΩ

resistors

Nonconductive

table (80 cm

above ground)

DUT0.1𝑚

VCP

(Vertical Coupling

Plane 0.5m x 0.5 m)

DUT remotely

accessible parts

0.1 𝑚

Direct

discharge

Indirect

discharge

Indirect

discharge

IEC 61000-4-2 – Test Set-Up for Table-Top Equipment



References

EMC Regulations:

FCC Part 15

CISPR 22

CISPR 25

ISO 11452-2

ISO 11452-4

ISO 11452-11

IEC 61000-4-2

IEC 61000-4-21

Special thanks to

Jim Teune and Scott Mee of

E3 Compliance LLC

for their technical expertise

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