A History of the Evolution of E Nieznany (2)

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A History of the Evolution of EMC Regulatory

Bodies and Standards

Donald Heirman

1

, Manfred Stecher

2

1

Don HEIRMAN Consultants, Lincroft, New Jersey, USA, d.heirman@ieee.org

2

Rohde and Schwarz, Munich, Germany, Manfred.Stecher@rsd.rohde-schwarz.com

Abstract — This paper provides a historical perspective of

the EMC regulatory environment and associated EMC
standards as they impact commercial products with empha-
sis in activity since WW II. It is focused in two parts: part 1
will deal with significant events in Europe while part 2 will
focus on the significant activity of the US Federal Communi-
cations Commission and two of the many US EMC stan-
dards writing bodies.

I. I

NTRODUCTION

When the word “interference” is mentioned, the public

generally sees this as a streak on their analog TV sets or a
buzz in their audio receiver or maybe even a drop out of a
mobile phone call. They believe that this should not
occur and that all of the newest electronics should work in
harmony no matter where they are used. This has placed
significant pressure on the manufacturers to create a
product that can work in its intended RF environment
while not causing undesirable interference or distur-
bances. This is called EMC or electromagnetic compati-
bility. How is this achieved? For some time now, there
has been regulatory requirements that limit the emissions
from products and in the European Union an essential
requirement that these same products be immune to a
certain level of these emissions from other products and
radio services. To assess the product EMC has required
that EMC standards be written and used. But how did
these regulatory requirements and EMC standards evolve
and what is the history leading up to present regimes?
This is the topic of this paper which will be presented in
two parts: Part 1: history of EMC regulations and stan-
dards in Europe and Part 2: similar background in the
United States focusing on the role of the Federal Commu-
nications Commission and two of the significant product
EMC standards resources

II. P

ART

1: E

UROPEAN

EMC R

EGULATORY

A

ND

S

TANDARDS

H

ISTORY

Introduction: Certainly, EMC problems occurred al-

ready with the distribution of telephony and telegraphy
around the world. Today we do not know very much of
such problems. A law of 1892 on telegraphy installations
signed by the Wilhelm II (German Emperor 1888-1918)
provides a legal solution for the problem of disturbance
coupled between lines of installations, which was impor-
tant enough to be included in the law [1].

RFI however proved to be a tremendous problem when

AM radio broadcasting started in the early twenties of

the last century. Since the author has detailed sources
about the development in Germany, this will be reported
first, which shall not preclude that the problems and solu-
tions were not similar in other European countries. But
the development shows that there was a real need for RFI
standards and regulation. In Germany, AM broadcasting
(“entertainment broadcasting”) officially started only in
October 1923. Besides that, there was other broadcasting,
e.g. broadcast for news agencies, telegraphic weather
broadcast, ocean broadcast and time broadcast [2]. In
1925 the Union Internationale de Radiotelephonie (UIR)
was founded in Geneva primarily for the allocation of
transmit frequencies.

Soon after the introduction of broadcast receivers in

private homes, lots of complaints were raised and it
became apparent that there were other users of the allo-
cated radio spectrum, like quenched-spark transmitters
for telegraphy, which had to be replaced by radio valve
transmitters between 1924 and 26 outside the frequency
band of 500 to 1500 kHz. Detailed investigations had to
be started on radio interference caused by tramways in
Berlin. Also in 1924 the High-Frequency Committee in
the VDE (Union of German Electrical Engineers) started
the development of guidelines for the protection of the
broadcast system against adverse effects. The Ministry of
Posts and Telecommunications (MPT) asked the regional
PTT offices to seek details about the complaints. Based
on the reports, the MPT asked the VDE to prepare tech-
nical measures for the avoidance of radio interference by
electrical equipment – especially against rf medical
equipment. Subsequently VDE 0759 (sometimes also as
VDE 478) on construction and test of rf medical equip-
ment was published in 1928 i.e. the first VDE standard
on radio interference measures [3].

Organisation of broadcast assistance. In 1926, the

MPT sent an order to the regional PTT offices for the
installation of local advisory boards for the solution of
daily complaints. With the help of radio clubs, radio
shops and the media, radio assistants were recruited on an
honorary basis and immediately the first guidelines on
radio assistance were published in 1926. In 1930 there
were already 2300 interference areas with 7300 radio
assistants. This new organisation grew further and in
1932 there were 5800 radio assistants (1480 from PTT)
and 2000 group leaders (1760 from PTT). Approx. 2500
interference-detecting instruments were available to them.
Since 1929 a broadcast commissioner was installed in the
MPT for the organisation of the radio assistance and of a

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The broadcast interference service continued after

1945. In 1950 they had 135 regional offices in West
Germany and were reorganised by 1952 to have 70 re-
gional offices and renamed to Radio Interference Meas-
urement Service. In the 1990ties the service was further
reduced to 26 regional offices with about 130 vehicles. In
2000 the total number of interference complaints was in
the order 17 000, with approx. 9200 (56%) dealing with
sound and TV broadcast. The reasons for this reduction
despite the increased amount of use of radiocommunica-
tion media are many-fold: use of FM instead of AM re-
ception, use of satellite TV instead of terrestrial and
increased use of digital radiocommunication systems.
Present estimates say that the actual number of com-
plaints arriving at the interference service is one sixth of
the real amount of interference cases to broadcast (audio
and TV) and one half of the amount of interference cases
to safety services.

scientific committee for interference to broadcast ser-
vices. During a World Energy Conference in Berlin 1930,
the broadcast commissioner requested the suppression of
disturbance in all types of electrical equipment and the
revision of the associated equipment specifications.

Legal situation. Radio listening had to be licensed and

the owner of a license had to pay a “broadcast fee”
(which is still the case in Germany). Unlicensed reception
was punished acc. to the “Law on Telegraphy” [3]. On
the other hand the owner of a license had the right to ask
for interference-free reception. A legal basis to fight radio
interference was given by the Law on Telecommunica-
tion Installations
, published on 14 Jan 1928 and by the
Citizen’s Rights Book (BGB) with paragraphs on the
protection of property. The request of experts for the
creation of a special law against broadcast interference
was however not fulfilled. The radio assistants solved
approx. 270 thousand interference cases between 1929
and 1932 by achieving mutual understanding between the
parties involved. Between 1927 and 1932 only a total of
130 cases had to be solved by the courts of justice and
88% of these ended in favour of the radio listeners.

RFI Regulation. The national authority on the alloca-

tion of radio frequencies was entrusted to the MPT. This
entailed the responsibility to keep the spectrum clean.
The PTT authorities were involved from the beginning in
the process of finding solutions to broadcast interference
as can be seen from the above. But the authorities only in
some cases dealt with the definition of test methods and
limits.

On 1 Oct. 1932 the MPT started the official Broadcast

Interference Service as a branch of the Telephone Dis-
turbance Service. The predecessor of the FTZ was in-
volved in the associated technical-scientific research. In
1938 both branches were separated. Fig. 1 shows the
number of radio listeners and the number of interference
complaints between 1930 and 1952. In spite of the fast
increasing number of radio listeners (4,5 millions in 1932
and 14,3 millions in 1940) the number of interference
complaints could be kept constant, still at a high level.

German National Standards were developed by the

radio interference committees of the VDE [3]. As men-
tioned above, the VDE started to work on RFI in 1924.
VDE 0759 on construction and test of rf medical equip-
ment was published in 1928. As no objective test meth-
ods were available, a subjective method was used,
applying a comparison with good radio reception. The
next standards were VDE 0870/1933 “Guidelines for
capacitors in broadcast and interference suppression
technology”, VDE 0873/1934 “Guidelines on measures
in supply line installations for the reduction of interfer-
ence to broadcast reception” and VDE 0874/1934
“Guidelines for measures in machines and apparatus for
the reduction of interference to broadcast reception”.
Based on these, VDE 0875/1941 “Rules for the suppres-
sion of radio frequency emissions of electrical machines
an apparatus with nominal powers up to 500 W” was
published. It became clear that it did not make sense to
specify the suppression components, but to develop ob-
jective methods of measurement. Obviously based on the
work in CISPR, two specifications were published in
March 1942: VDE 0876 “Specifications for apparatus for
the measurement of disturbance voltage” defining the
measuring receiver with quasi-peak detector for a fre-
quency range of 0,1 to 20 MHz and VDE 0877 “Methods
of measurement of disturbance voltage” defining the
Artificial Mains V-Network (LISN) with 150

ȍ imped-

ance between line and ground – in contrast to the CISPR
ǻ-network (see below). No justification has been found
for the preference of the V to the

ǻ-network. In VDE

0878/8.1943, all the experience was included in new
“Rules for the suppression of radio disturbance from
machines, apparatus and installations”, which does away

Statistics of Complaints

1

10

100

1000

10000

100000

30

35

40

45

50

Year

x1

00

0

No of Listeners
No of complaints

Fig. 1: The numbers of radio listeners and interference
complaints in Germany between 1930 and 1952.

Due to the work of the broadcast interference service,

statistics of complaints are available. The main sources
of interference before 1939 were small motors and elec-
trical tools in household and small business (30%), medi-
cal electrical equipment (decreasing from 12% to 4%),
power supply networks (12%), erroneous receiving sys-
tems (32%) and atmospheric resp. undefined sources of
interference (16%)

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with all subjective test methods and applies the objective
method of measurement of the disturbance voltage. Tak-
ing this into account, VDE 0875/11.1951 replaced VDE
0878. The introduction of FM audio and TV broadcast in
the VHF frequency range required a limitation of emis-
sions from ISM equipment, which led to the publication
of VDE 0871 Part 1/9.1952.

In 1949, Germany published the Law on Radio Fre-

quency Equipment (Hochfrequenzgerätegesetz, HFrG)
which stated that the user of apparatus which generates or
uses electromagnetic energy in the frequency range of
10 k to 3000 GHz (radio frequency apparatus) needed a
permit. There were individual and general permits. Per-
mits were granted only if the apparatus fulfilled the Tech-
nical Specifications of the PTT, which were - with some
exceptions - identical with the limits of VDE 0871 (for
NB disturbance, later also digital devices), VDE 0875
(for BB disturbance) and VDE 0879 (for motor vehicles).
In the 1980’s the VDE 0878 for telecommunication
equipment and ITE was added. General permits for the
operation of broadcast receivers, with limits defined in
VDE 0872, were still based on the Law on Telecommu-
nication Installations, using an “FTZ-mark”. General
permits and the conditions under which these permits
were granted, were published in the Official Gazette
(Amtsblatt) of the MPT as decrees (in German: Ver-
fügungen (“Vfg”)). An important step was the publication
of Vfg 478/1981, setting into force immunity require-
ments for broadcast receivers developed by the FTZ. The
reason was that one of the interference problems always
had been the lack of immunity of receiving equipment to
conducted or radiated EMI. Later, similar requirements
were included in VDE 0872 parts 2 to 5 and CISPR 20.
For a long time, the VDE Testing and Certification Insti-
tute had been accepted as the only testing authority in
Germany, issuing the radio protection mark (f-mark).
Many details about the situation around 1985 can be
found in [4].

Like other NCs, the VDE committee on RFI continued

to develop national standards in liasion with the CISPR
and the CENELEC until about 1989, when the Vilam-
oura-Agreement
of 1988 came into force. European
NCs henceforth had to ask other CENELEC NCs, whe-
ther they were interested in specific standardisation pro-
jects, thus avoiding the creation of barriers to trade and
preparing for the Internal European Market in 1992.

Some history on RFI/EMC standards and regulatory

activities in other European Countries

Until about 1961, German Democratic Republic

(GDR) representatives used to take part in West German
NC meetings. Only after that, the GDR decided to de-
velop their own standards, which resulted in a set of 17
RFI-relevant TGL 20 885/1 … 21 standards. Some of
them were closely related to CISPR standards, some were
added, e.g. for traction systems and power stations [7].

Some information is available about Italy: they trans-

posed the EEC Directives 889 and 890 of 1976 into Na-
tional Law and in 1985, the immunity requirements for
broadcast receivers became mandatory in the frame of a

National Law [8]. The IMQ-mark was the Italian equiva-
lent of the German f-mark.

In The Netherlands the Minister van Waterstaat (of

Public Works) decided to start an investigation in the
problem of radio interference in 1931 and initiated the
establishment of the Radiostoringscommissie which re-
sulted in the first legislation related to radio interference
the so-called “Radiostoringsreglement” in 1935. The PTT
as a governmental organisation had to deal with the com-
plaints and to exercise supervision [5].

In Poland, work on radio interference started in 1935.

The first standard PN/E-58 on “Guidelines for the sup-
pression of interference to broadcast reception due to
various electrical appliances” was published in 1937.
After WWII, everything needed reconstruction. In order
to deal with RFI, a research laboratory was installed in
the Institute of Telecommunication in Wroclaw in 1956
by W. Rotkiewicz. A legal framework for RFI reduction
was the Telecommunication Law of 1962. Rotkiewicz
also chaired the standardizing committee and worked in
close cooperation with other COMECON countries (e.g.
Czechoslowakia with T. Dvorak [e.g. 19], later the foun-
der of the Zurich EMC symposium) and in 1972 the first
Wroclaw EMC Symposium was organized, which ap-
peared to be the 1

st

regular EMC symposium in Europe.

From Switzerland material is available from the 1930’s

and one of the first European decrees specifically on RFI
was published in Jan. 1935 [21]. Many contributions to
international standardisation were provided by members
of the Swiss NC [22]. Also many committee chairmen
both in CISPR and in TC77 came from Switzerland. Not
being a member of the EU or the EEA, Switzerland still
applies the European EMC Directive. The Bundesamt für
Energiewirtschaft (Federal Office for Power Industry) is
the Competent Authority.

For the United Kingdom, many details about the early

history of RFI can be found in [12]. Many papers on RFI
were published in the 1920’s as the BBC was established
in 1922. In 1933 the IEE formed a committee on RFI.
The 1

st

standard was BS 613 “Components of Radio In-

terference Suppression Devices” in 1935 and BS 727 on
“Characteristics of Radio Interference Measuring Instru-
mentation” as well as BS 800 on “Limits of Radio Inter-
ference” were published in 1937. National legislation was
available as the Wireless Telegraphy Act of 1949.

History of the CISPR

There was general agreement that the most important

international problem was to secure uniformity in the
methods of measurement and in the specification of limits
to avoid difficulties for the exchange of goods and ser-
vices [10]. In 1933 an ad-hoc conference of interested
international organisations was held in Paris to decide
how the subject of radio interference should be dealt with
internationally. It was agreed to form a Joint Committee
of the International Electrotechnical Committee (IEC)
and the UIR. The 1

st

meeting of the CISPR (then called

“Comité International Spécial des Perturbations Radio-
phoniques” (only in 1953 in view of the importance of

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television, the last word was replaced by “Radioélectri-
ques”) was in June 1934 in Paris, with representatives of
6 national committees of the IEC (Benelux, France, Ger-
many and UK), the UIR and of other international organi-
sations as the International Union of Producers and
Distributors of Electrical Energy (UNIPEDE), the Inter-
national Conference on Large High Tension Electric
Systems (CIGRE), the International Union of Railways
(IUR) and of the World Power Conference. The Comité
Consultatif International de Radio (CCIR) did not wish to
become a full member. In the first meeting two Subcom-
mittees (SCs) (A on limits and B on measuring methods)
were founded [9]. The proposal to “measure the high-
frequency interference voltage at the terminals of the
interfering electrical appliance” and to “evaluate the at-
tenuation of the interference between the source and the
input terminals of a receiver on the basis of statistical
experimental data” was proposed by Germany and The
Netherlands. International work continued until 1939
(with meetings held in Berlin Dec. 1934 and April 1935,
in London Nov. 1935 and May 1936, Brussels in March
and Dec. 1937 and in Paris in July 1939). The recom-
mendations of CISPR were contained in the proceedings
of the meetings and Reports RI Numbers 1 to 8 cover the
period up to 1939.

The CCIR did not become a CISPR member but later

(in 1966) they adopted a recommendation (433), that as
far as possible, administrations should take into account
the recommendations, reports and publications of the
CISPR and that national regulation concerning interfer-
ence suppression should be based on the measuring meth-
ods and apparatus described by the CISPR. There was
and is a clear division of work: interference between
radio services or between transmitters of the same service
is in the province of the CCIR (now ITU-R) and not the
CISPR. The member nations of the ITU have signed the
International Telecommunications Convention, urging
the national administrations to keep radio interference
levels as low as possible and which is a basis for national
laws on interference suppression.

Agreement was reached on the CISPR delta network

that makes it possible to measure the symmetrical (differ-
ential mode) and asymmetrical (common mode) compo-
nent of the disturbance voltage [10]. In 1937, provisional
limits were proposed for the symmetrical voltage of 3 mV
from 160 to 240 kHz and of 1 mV from 550 to 1400 kHz
and for the asymmetrical voltage of 1,5 mV both from
160 to 240 kHz and from 550 to 1400 kHz. In 1939
twelve copies of the 1

st

CISPR measuring receiver (de-

signed in Belgium) were ready. Its frequency range in-
cluded the long wave and medium wave bands (150 to
1500 kHz) and it had essentially the characteristics of
today’s CISPR quasi-peak measuring receiver for Band B
(0,15 to 30 MHz) with 9 kHz bandwidth and 1 ms charge
time and 160 ms discharge time constant of the detector.
The spread of results of measurement on a standard
commutator motor in different countries was however
disappointing.

International CISPR work restarted in 1946 – from

now on with a strong delegation from the USA. Canada,
Japan and since 1956 the USSR also took part in the
meetings. In 1956 delegates from 17 countries took part
in the meeting. In the meeting of 1946, it was recognised
that measurements would be required for frequencies
greater than 1.6 MHz and that major receiver design
would be required for frequencies greater than 20 to 30
MHz. At this meeting the measurement of the rf voltage
at the mains terminals of an appliance using the 150

ȍ V-

network was proposed [11]. In 1950, CISPR was decided
to be formally constituted as a special committee of the
IEC [12]. The recommendations and reports continued to
appear in the proceedings of the Plenary meetings and the
numbers RI 11 to 14 covered sessions in Paris 1950,
London 1953, The Hague 1958 and Brussels 1959. Con-
siderable progress was made on the specifications for
measuring receivers and techniques for the frequency
ranges 0,15 to 30 MHz and 30 to 300 MHz and both
CISPR publications 1 and 2 appeared in 1961. In 1953
a steering committee was formed to aid the chairman and
SC C on Safety Aspects of Interference Suppression was
added. In 1958 eight working groups were established.
[10] gives the status of work up to 1970 as follows:

- WG1 on Radio Interference Measuring Equipment
which until 1967 defined all measuring receivers from 10
kHz to 1000 MHz including publications 1 through 4.

- WG2 on Interference from ISM equipment. Radiated
emission limits were published as recommendations in
the frequency range 0,15 to 1000 MHz.

- WG3 on Interference from Overhead Power Lines and
High Voltage Equipment

- WG4 on Interference from Ignition Systems and Inter-
nal Combustion Engines. Until 1970, limits were given
for 30 to 300 MHz. At this time limits were also consid-
ered up to 1000 MHz. Limits for interference to radio
reception on the vehicle itself were under discussion but
it took until 1995 when CISPR 25 appeared.

- WG5 on Interference and Immunity Characteristics of
Audio and TV receivers.

- WG6 on Interference from Motors, Domestic Appli-
ances, Lighting Apparatus and the like. Interference in the
frequency range up to 300 MHz was a difficult item be-
cause different countries used different measurement
methods, ranging from open site field-strength measure-
ments, stop filter tuned supply cord substitution meas-
urements, earth current measurements to terminal voltage
measurements. Finally agreement was reached on a
method proposed by Meyer de Stadelhofen of Switzer-
land, Chairman of the WG [20]. Also limits have been
approved for thermostatically controlled apparatus emit-
ting discontinuous disturbance, e.g. irons and refrigera-
tors using the counting of clicks and applying click
weighting.

- WG 7 on the Impact of Safety Regulations on Interfer-
ence Suppression. The chairman of this WG was a mem-
ber of the IEC Committee on Safety (A.C.O.S.).

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- WG 8 on Statistical Methods and Correlation between
Measured Value and Disturbing Effect. A recommenda-
tion on the Significance of a CISPR limit was approved in
Leningrad (1970) which implies that type approval may
be made on the basis of measurements of a single sample
whereas conformity of production should be ensured on a
statistical basis.

- WG 9 on Terminology which contributed a chapter to
the International Electrotechnical Vocabulary (IEV)

- WG 10 on Lists of Complaints. This was necessary in
order to harmonize the national lists of complaints for
better comparability.

In the period of 1961 – 1973 CISPR saw the appear-

ance of Recommendations in Pub. 7 (1966), Reports and
Study Questions in Pub. 8 (1966) and National Specified
Requirements and Legal Regulations in Pub. 9 (1966).
Besides the Pubs. 3 and 4, Pub. 5 specifying the peak,
average and rms detectors appeared in 1968. In 1973
CISPR was reorganized by reconstituting the WGs as
Technical SCs, each with its own national secretariat,
thus sharing the burden which hitherto had fallen to the
CISPR secretariat.

Period 1973 to 1986. In 1973 the decision was made to

incorporate all measuring receiver details and the com-
mon measurement techniques into one publication (No.
16) covering the work of SC A and to create self-
contained publications including reports, recommenda-
tions and limits and specialised measurement methods.
Thus Pubs. 11 to 15 came into existence on the subjects
of ISM, motor vehicles, radio and TV receivers, house-
hold appliances and fluorescent lighting and covering the
work of SCs B, D, E and F. The work of SC C on high
voltage lines appeared at a later stage in Pub. 18. It had
also become evident that digital electronic equipment,
microprocessors etc. could be a serious source of inter-
ference to radio reception and this was recognised in
1975 by creating a working group reporting first to the
steering committee and later to SC B. This working group
was reconstituted in 1985 as an SC with the terms of
reference to include Information Technology Equipment
and was responsible for Pub. 22, the 1

st

edition of which

appeared in the same year, doing away the problem of
NB/BB discrimination and establishing the first time
limits for QuasiPeak and Average detections in conducted
emission measurements. Pub. 20 for the immunity of
sound and TV broadcast receivers, the first international
commercial immunity product standard was published in
1985 to which the Italian NC provided many contribu-
tions [8].

Period 1987 to 2004. In these years, much effort was

expended in the development of CISPR Pub. 16 to be-
come “The CISPR Handbook”. Measurements in the field
of EMC for a long time were known as “estimation with
expensive test equipment”. Therefore the work concen-
trated on improving the reproducibility of measurement
by adding requirements for test site validations, require-
ments for measurement uncertainty and by improving the
definitions of the test methods and setups. Major steps
forward were the publications of CISPR 16-4:2002 on

measurement uncertainty and of reports on compliance
uncertainty in CISPR 16-4-1:2004. SC G developed the
CISPR 24:1997 “Immunity of ITE”, using the test meth-
ods in IEC 61000-4-x as basic standards. Also SC F pub-
lished CISPR 14-2:1997 “Immunity of Household
Equipment etc.” In 1999 CISPR created a new SC H on
the development of limits. In 2000 SC C was dissolved
and the merging of SCs E and G was decided to form a
combined SC I taking into consideration that multi-media
equipment was in the scope of E and G. Most of the
CISPR work is well described by the publications devel-
oped between about 1990 and today:

10:2001-08 Rules and Procedures of CISPR
11:2004-06 Limits and measurement methods: ISM
12:2001-09 Automobiles and ignition systems
13:2003-03 Emission of sound and TV receivers
14-1:2002-10 Emission household appliances etc.
14-2:2001-11 Immunity of household appliances etc.
15:2002-10 Emission of fluorescent and lighting eq.
16:2003…4 Equipment, methods and reports of EMC

testing (14 parts)

17:1981-01 Test methods of EMI filters
18:1982…96 Overhead power lines, phenomena, limits,

test methods, suppression (3 parts)

19:1983-01 Microwave oven substitution measurement
20:2002-02 Immunity of sound and TV broadcast rec.
21:1999-10 Mobile radio reception in presence of im-

pulsive noise

22:2003-04 Emission of IT equipment
23:1987-12 Determination of limits for ISM equipment
24:1997…02 Immunity of IT equipment
25:2002-08 Emission limits for radio reception in cars
28:1997-04 ISM equipment – guidelines for emission
29:2004-08 TR: Immunity of TV receivers – methods

of objective picture assessment

30:2001-02 TR: Test method on EM emissions from

fluorescent lamps

31:2003-10 Database on the characteristics of radio

services

Generic emission standards:
CISPR 61000-6-3:1996-12 Emission for resid., commerc.

and light-industr. environments

CISPR 61000-6-4:1997-01 Emission for industrial env.

A short history of IEC TC77

TC 77 was established in 1973 and held its 1

st

meeting

in Bucharest 1974 [13]. Its title was “EMC between elec-
trical equipment including networks” and its scope: To
prepare international recommendations concerning elec-
tromagnetic compatibility of electrical and/or electronic
equipment between themselves and with the mains supply
network.” The first publications – developed in 7 working
groups - were IEC 555-1, -2, -3: Disturbances in supply
systems caused by household appliances and similar elec-
trical equipment (1: Definitions, 2: Harmonics, 3: Voltage
fluctuations) and IEC 725: Considerations on reference
impedances

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1981 1

st

reorganisation of TC77 with two SCs:

SC 77A Equipment connected to the public low-voltage
supply system (1

st

meeting 1983)

SC 77B Industrial and other non-public networks and
equipment connected thereto (1

st

meeting 1983). Publica-

tions were IEC 816: Guide on methods of measurement
of short duration transients on low-voltage power and
signal lines and IEC 868: Flickermeter – Functional and
design specifications. Before 1991 a great number of the
publications 61000-x-y reached a mature stage, although
not yet published. Also TC 77 started to deal with high-
frequency phenomena.

1991 Enlargement of TC 77 – Setting up of SC 77C:

Immunity to high altitude nuclear electromagnetic pulse
(HEMP) (1

st

meeting in 1992) and 2

nd

reorganisation of

TC 77: Phenomena/frequency range oriented with a new
structure:

TC77 Parent committee dealing with general matters

like terminology and safety

SC 77A Low frequency phenomena (f

” 9 kHz)

SC 77B High frequency continous and transient phenom-

ena (f

• 9 kHz in coordination with CISPR)

SC 77C Immunity to HEMP

Publications (standards and reports) developed by TC 77

IEC 61000 Electromagnetic compatibility:

Part 1 General
-1-1:1992-05 Fundamental definitions and terms
-1-2:2001-06 Methodology for functional safety
-1-3:2002-06 The effects of HEMP to civil equipment
-1-5:2004-11 HPEM effects on civil systems

Part 2 Environment
-2-1:1990-05 Low frequency (LF) conducted disturban-

ces and mains signalling

-2-2:2002-03 Compatibility levels for LF conducted dis-

turbances (CD)

-2-3:1992-10 Radiated and non-network-frequency-rela-

ted conducted phenomena

-2-4:2002-06 Compatibility levels in industrial plants for

LF CD.

-2-5:1995-09 Classification of EM environments
-2-6:1995-09 Emission levels in power supply (PS) of

industrial plants for LF CD.

-2-7:1998-01 LF magnetic fields in various environments
-2-8:2002-11 Voltage dips, short interruptions and statis-

tical measurement results

-2-9:1996-02 Description of HEMP environment – radi-

ated disturbances

-2-10:1998-11 Description of HEMP environment – CD
-2-11:1999-10 Classification of HEMP environment.
-2-12:2003-04 Compatibility levels for LF CD and sig-

nalling in public MV PS systems

Part 3 Limits

(-3-1) Overview of emission standards and guides
-3-2:2004-11 Harmonic current limits (current

” 16 A)

-3-3:2002-03 Voltage fluctuation limits (current

” 16 A)

-3-4:1998-10 Harmonic current limits (current

• 16 A)

-3-5:1994-12 Voltage fluctuation limits (current

• 16 A)

-3-6:1996-10 Assessment for distorting loads in MV and

HV power systems

-3-7:1996-11 Assessment for fluctuating loads in MV and

HV power systems

-3-8:1997-09 Signalling on LV installations – emission

levels etc.

(-3-9) Interharmonic current limits (current

” 16 A)

(-3-10) Emission limits in the frequency range 2 … 9 kHz
-3-11:2000-08 Limits of voltage changes, fluctuations

and flicker (I

” 75 A)

-3-12:2004-11 Limits for harmonic currents for equipm.

connected to public LV PS systems (16 A < I

” 75 A)

Part 4 Test Methods
-4-1:2000-04 Overview of immunity tests
-4-2:2001-04 ESD immunity tests
-4-3:2002-09 Radiated RF EM field immunity test
-4-4:2004-07 EFT/burst immunity test
-4-5:2001-04 Surge immunity test
-4-6:2004-11 Immunity to conducted disturbances,

induced by RF fields

-4-7:2002-08 Guide on harmonics and interharmonics

(HI) meas. and instrumentation

-4-8:2001-03 Immunity to power frequency magn fields
-4-9:2001-03 Pulse magnetic field (MF) immunity test
-4-10:2001-03 Damped oscillatory MF immunity test
-4-11:2004-03 Voltage dips, short interruptions and volt.

variations immunity tests a.c.

-4-12:2001-04 Oscillatory waves immunity test
-4-13:2002-03 HI incl. mains signalling at ac power port

LF immunity tests

-4-14:2002-07 Voltage fluctuations immunity test
-4-15:2003-02 Flickermeter, functional and design specs
-4-16:2002-07 Test for immunity to conducted, CM

disturbances in 0 Hz to 150 kHz

-4-17:2002-07 Ripple on d.c. input power port immunity
-4-20:2003-01 Emission and immunity testing in TEM
-4-21:2003-08 Reverberation chamber test methods
-4-23:2000-10 Test meth. for protective devices for

HEMP and other rad. disturbances

-4-24:2000-10 Test meth. for protective devices for

HEMP conducted disturbances

-4-25:2001-11 HEMP immunity test meth. for equipment

and systems

-4-27:2000-08 Unbalance immunity test
-4-28:2002-07 Immunity to variation of power frequency
-4-29:2000-08 Voltage dips, short interruptions and volt.

variations immunity tests d.c.

-4-30:2003-02 Power quality measurement methods
-4-32:2002-10 HEMP simulator compendium

Part 5 Installation and Mitigation Guidelines

-5-1:1996-12 General

considerations

-5-2:1997-11 Earthing and cabling
-5-3:1999-07 HEMP protection concepts
-5-4:1996-08 Specs. for protective devices against

HEMP radiated disturbance

-5-5:1996-02 Specs. for protective devices for HEMP

conducted disturbance

-5-6:2002-06 Mitigation of external EM influences
-5-7:2001-01 Degrees of protection provided by enclo-

sures against EM disturbances

88

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Part 6 Generic Standards
-6-1:1997-01 Immunity for residential, commercial and

light-industr. environments

-6-2:1999-01 Immunity for industrial environments
-6-5:2001-07 Immunity for power station and substa-

tion environments

-6-6:2003-04 HEMP immunity for indoor equipment

Joint Task Forces (JTFs) of CISPR SCA with SC77B

were established in 1997 to develop standards of common
interest, one for emission and immunity testing in TEM
waveguides and one for reverberation chamber test meth-
ods (see IEC 61000-4-20 and -21). Further two JTFs
were established in 2002, one for the validation of fully
anechoic rooms (FARs) for emission and immunity test-
ing and one for uniform measurement arrangements for
radiated emission and immunity testing.

Origin of IEC 61000-4-1, -2, -3, -4 and -5: these stan-

dards have their origin in IEC 65A/WG4, which started in
1978 and published the first edition of IEC 801-2 and -3
in 1984, -4 in 1988 and -5 in 1991. In the 1990’s IEC
801-x standards were revised and published first as IEC
1000-4-x and later – accepting a structure used by
CENELEC – as IEC 61000-4-x. IEC 65A/WG4 is now
developing EMC standards IEC 61326-x for electrical
equipment for measurement, control and laboratory use in
cooperation with IEC TC 66.

Another international committee on EMC is ISO

SC22/3. They are developing ISO 7637 for conducted as
well as ISO 11451 and ISO 11452 on vehicle and com-
ponent radiated immunity tests [14].

CENELEC. The original 6 countries of the European

Economic Community (EEC) had established a technical
committee to develop common standards for radio inter-
ference and to eliminate possible barriers to trade within
the Common Market. When the EEC expanded to nine
countries in 1973 the European Standards Committee
(CENELEC) was formed with the membership extended
to include the countries of the European Free Trade Area
(EFTA). The CENELEC TC-CISPR developed the first
two European Standards dealing with household appli-
ances and fluorescent lighting, which were published as
Directives 76/889/EEC and 76/890/EEC in 1976 which
already offered the manufacturer’s declaration of confor-
mity. These were implemented in the National Legislation
of the nine EEC countries [11], e.g. in Germany as the
Law on Radio Interference (Funkstörgesetz) of 1978. The
technical specifications were given in VDE 0875-1 and -
2. Later the CENELEC – with the advent of the European
EMC Directive decided to adopt CISPR standards as EN
55 0xy and IEC EMC standards as EN 61 000-x-y.
Where no international standards were available,
CENELEC TC 110 (now 210) developed EN 50 xyz, e.g.
the first Generic Emission Standards EN 50 081-1 and -2.
ETSI standards [15] later were published as EN 30w xyz,
e.g. EN 300 386 on the EMC of telecommunication net-
works equipment. Presently CENELEC and ETSI have
got the mandate to develop an EMC standard for tele-
communication networks including telephone, coaxial
and PLC networks.

The European EMC Directive 89/336/EEC [16] is a

new-approach directive in that it does not contain techni-
cal requirements but defines protection goals only: emis-
sion and immunity. Compliance with the protection
requirements is presumed if equipment complies with
harmonized European standards, the reference numbers
of which have been published in the EC Official Journal.
In normal cases, the manufacturer or the importer writes
the EC declaration of conformity and affixes a “CE”-
mark of conformity to the product. The former national
regulators have the task of market supervisors. Special
provisions apply if harmonized standards have not been
used. In contrast to this, the Automotive EMC Directive
95/54/EC
updating 72/245/EEC to technical progress,
contains detailed technical requirements. Both EMC Di-
rectives went into force on 1 January 1996. Recently
Directive 95/54/EC has been replaced by 2004/104/EC
[18] and a new EMC Directive [17], replacing
89/336/EEC, is close to publication.

III P

ART

2: USA C

OMMERCIAL

EMC R

EGULATORY

A

ND

S

TANDARDS

H

ISTORY

The Communications Act of 1934 in the United States

gave the US Federal Communications Commission the
authority to protect the use of the radio spectrum from
interference from radio transmissions that were not so-
called licensed users of the spectrum. For many years,
the requirement for reducing interference from low power
incidental radiators (those generating RF but not for use
in broadcasting this energy to receivers) was 15 uV/m at a
distance of a wavelength divided by 2 pi. This general
requirement served well until a decade or so after WW II
where as the frequency of digital devices started to in-
crease to well beyond 100 MHz, the measurement dis-
tance to show compliance to the 15 uV/m limit became
less than a meter away and clearly became a measurement
in the near field of the RF source. As the frequencies
became higher, the measurement distance approach the
source so close as to make it impossible to measure using
antennas designed to operate in those frequency ranges.
Thus it was clear that this limit and measurement method
had outlived its usefulness.

Art Wall, Deputy Chief of the FCC Labs, and major au-

thor of the much discussed FCC Part 15 rules on low
power RF devices has provided a clear description of the
improvement in the interference control which became
needed in the 1960’s and 1970’s. From his paper, a time-
line of the historical FCC rules for digital devices can be
drawn and are now reviewed. [23]

In this time frame, TV interference became to increase

caused by the new personal computers that started to be
used. Other sources of interference initially identified
were electronic coin operated video games which caused
interference to highway police communications at 42
MHz, and electronic cash register systems interfering with
safety communication systems, as well as the new per-
sonal computers introduction. By the late 1970’s the
FCC’s field engineers expended significant time resources
to track down these interference sources.

89

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In 1976, the FCC started a proceedings (FCC Docket

20780) on limiting radiated and conducted emissions
from computers. [24] The changes were to the existing
Part 15.7 of the FCC rules which while were meant to
address computer emissions, it was inadequate to handle
the new digital devices and speeds in computers of the
era. Then in 1977 the Computer Business Equipment
Manufacturer (CBEMA) (later renamed Information
Technology Industry Council (ITIC)) responded to the
proceedings with data showing the if limits were to be
introduced, there needed to be a 10 dB difference be-
tween limits allowed in a residential environment com-
pared to that in a commercial environment arguing that
the higher limit would be tolerated in more noisy com-
mercial locations. The FCC adopted much of the propos-
als in the CBEMA report and then established limits
based largely on the CBEMA surveyed data from existing
computer installations. The limits were set such that the
highest computer emissions from the over 100 prod-
ucts/installations measured would have to be suppressed,
yet the majority would still meet the new limits and hence
was achievable with current technology at that time.

All this activity led to the now famous FCC Docket

20780 in 1979 which was the first report and order of the
FCC that set technical standards (emission limits) for
computing equipment. [24] This set the administrative
and technical standards, which have to be met for digital
devices to be legally marketed in the USA. Subsequent to
this R&O, there were other FCC rulings that provided
product exemptions, broadened the application to digital
devices other than just computing devices, and changed
the referenced clauses in the FCC Rules under Part 15 of
the Code of Federal Regulation. The exemptions still
hold today and include:

a.

Digital devices used in transportation vehicles

b.

Digital devices used in commercial and industrial
control and power equipment

c.

Digital devices used in appliances (here appliances
are those used in the home such as mixers, refrig-
erators, etc.)

d.

Commercial and industrial test equipment

e.

Supervised medical digital devices

f.

Digitals devices with total power less than 6 nW

g.

Joysticks and similar computer controllers

h.

Digital devices with internally generated and used
frequency sources less than 1.705 MHz

This paper will not go into the limits or their application

to products as that is a subject of considerable discussion,
which is described in reference [23]. The net effect is
that radiated emission limits were in effect between 30
MHz and 40 GHz for close to a quarter century as of this
writing. Limit deliberations above 1 GHz are presently
being debated and experiencing difficulty in being ac-
cepted with a positive national committee vote in the
International Electrotechnical Commission (IEC) Special
International Committee Radio Interference (CISPR) and
in regional areas such as the European Union. So in the
meantime, the FCC limits are still the prevailing regula-
tory requirement—at least for marketing products in the

USA. It is further interesting to note that the conducted
emission limits between 150 kHz and 30 MHz and the
radiated emission limits between 30 and 1000 MHz are
now harmonized with that of CISPR 22 and its counter-
part EN55022. The FCC limits above 1 GHz however
remain. Also it should be reported that the method of
measurement of these emissions is via the use of ANSI
C63.4-2003 and not that contained in CISPR 22 or
EN55022. There are major similarities between CISPR
22 and C63.4, but the differences are such that attention
needs to be paid to using only C63.4 for compliance with
the FCC Rules. Two examples of the differences are that
C63.4 does not have telecom port measurement require-
ments nor does it allow a choice between using a 40 cm
high table or a 80 cm high table for performing conducted
emission measurements—both of these are allowed in
CISPR 22/EN55022.

Future FCC regulatory Activity:

In reference [23], the author indicates that major areas

of FCC regulatory activity are focusing on RF sources
operating above 1 GHz. These include:

a.

Mobile satellite services

b.

Digital audio radio services

c.

Global positioning systems

d.

Ultra-Wideband transmissions

e.

Unlicensed National Information Infrastructure de-
vices

f.

Devices that cannot transmit if an authorized radio
service is detected (listen before talk)

While the above services are in the band between 1 and

6 GHz, there are also allocated bands well into the 10’s of
GHz and above range that has yet to be fully exploited.

History of IEEE EMC Society EMC standards

For over 50 years, there have been EMC standards as-

sociated with the IEEE, even before the IEEE was estab-
lished in 1963. Table 1 summarizes the standards activity
of the EMCS which is now further elaborated [25]. Earli-
est records show that the first EMC standard, which be-
came the responsibility of the IEEE EMC Society, was
Standard 140, which was released in 1950. The subject
was a recommended practice for minimization of interfer-
ence from radio-frequency heating equipment. This
document recommended ways to minimize emissions
from RF heating equipment by provided procedures to be
used when interference is encountered, locating the
sources of the interference and then applying corrective
measures such as source frequency shifting, automatic
frequency control, and improving source shielding includ-
ing tightening of shielding fasteners around the heating
equipment doors.

In 1952, a companion Recommended Practice was pub-

lished as Standard 139 on In-situ measurements of RF
from industrial, scientific and medical equipment. This
was an a continuation of the work in Standard 140 but
more specifically addressed in-situ measurements of the
emissions from the ISM equipment on the user’s prem-
ises. It includes the effects of nearby RF sources for

90

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which its emissions may interact with the ISM emissions
to create harmonically related spurious frequencies.

In 1951, there was concern for determining the interfer-

ence potential of spurious emissions from FM and TV
broadcasting receivers creating interference. These
sources included local oscillator circuits, Intermediate
frequency amplifier, oscillators associate with cathode-
ray-tube operation, TV sweep circuits, etc. Standard 187
provided a way to measure these spurious emissions at an
open field test site.

By 1961, there was a need to have a common repeatable

way to measure conducted emissions into the power line
from the same FM and TV broadcasting receivers. This
lead to Standard 213 which provided the measurement
procedure in the frequency range 300 kHz to 25 MHz
using a Line Impedance Stabilization Network (LISN)
using a 5 uH, 50 ohm system. A companion standard
containing the construction details for this LISN was
published the same year as Standard 214. (By 1987, both
standards were included in the revised standard 213.)

In 1969, there was a significant standards introduced. It

was Standard 299, which provided a method for measur-
ing the effectiveness of large electromagnetic shielding
enclosures. The frequency range that it was applicable
was 14 kHz to 18 GHz but had suggestions to extend the
range down to 50 Hz and up to 100 GHz. This standard
had more applicability than MIL STD 285 which had
been the referenced standards for military use for years.
For example, Standard 299 introduced the use of a test
plan prior to starting the effectiveness measurements. It
also provided guidance on frequencies to test other than
those at the lowest natural resonant frequency of the en-
closure.

Going into the 1970’s, the EMC Society standards

committee started work on other EMC measurement stan-
dards in particular. At the end of 1974 and into 1975, the
next standard by the IEEE EMC Society dealt with the
use of an impulse generator to calibrate automatic spec-
trum scanning instrumentation of the day. Interestingly,
the use of impulse bandwidth given in Std 376 even today
is being accepted for calibration of spectrum analyzers.
So this ground breaking standard of over a quarter of a
century ago is still of interest even today. In 1971,
worked with the IEEE Vehicular Society (then called
Group as was the EMC Society), the Electronics Indus-
tries Association (now an Alliance), and the IEC to estab-
lish a standard to measure the spurious emissions from
Land-mobile communication transmitters primarily in the
25 MHz to 1000 MHz band. This work was published in
1980 as Standard 377. In 1985, the EMC Society stan-
dards committee published a recommended practice for
site survey measurements in the range 10 kHz to 10 GHz.
This recommended practice introduced one of the first
approaches to measuring RF ambient inside buildings as
well as in obstruction free areas outside. In 1983, the
work shifted to developing measurement procedures for
field disturbance sensors and RF intrusion alarms as
Standard 475. The radiated emission procedures covered
the range of 300 MHz to 40 GHz while the power line

conducted emission procedures addressed the 30 to 300
MHz range.

The 1990’s produced the next EMC Society standard

that addressed simpler measurements of electric and mag-
netic emissions from video display units in the frequency
range 5 Hz to 400 kHz. This standard 1140 that was
published in 1994 was similar to that published in Sweden
at the time but used a lesser set of measurement points. In
1998, the first guide to characterize the RF characteristics
of conductive gaskets in the frequency range DC to 18
GHz was published. It contained several techniques and
provided a guide to select the best method depending on
the application. Two years earlier in 1996, the first IEEE
standard on calibrations of field probes, excluding anten-
nas, in the frequency range 9 kHz to 40 GHz was pub-
lished. It included the use of TEM cells, Helmholtz coils,
open-ended waveguides, pyramidal horns and other tech-
niques for generating the calibration field.

Currently, the IEEE EMC Society is working on new

projects including the last 5 shown in Table 1. The sub-
jects of these standards convey the essence of the pro-
jects. In addition there are several study questions under
consideration including

a.

Development of standards supporting the next gen-
eration radio and advanced spectrum management.

b.

Support of a GTEM user group and standards that
might proceed based on the group’s experience

c.

Review of wireless performance prediction for lo-
cal area networks standards.

Further progress on these studies will be presented at the
session.

Table 1: IEEE EMC Society Standards

139-1988
Recommended
Practice

Measurement of Radio Frequency
Emission from Industrial, Scientific,
and Medical (ISM) Equipment In-
stalled on User's Premises

187-2003
Standard

Radio Receivers: Open Field Method
of Measurement of Spurious Radia-
tion from FM and Television Broad-
cast Receivers

213-1987
(R1993, 1998)
Standard

Measuring Conducted Emissions in
the Range of 300 kHz to 25 MHz
from Television and FM Broadcast
Receivers to Power Lines

299-1997
Standard

Measuring the Effectiveness of the
Electromagnetic Shielding Enclosure

377-1980
(R1991, 2003)
Recommended
Practice

Measurement of Spurious Emission
from Land-Mobile Communication
Transmitters

473-1985(R1991)
Recommended
Practice

Electromagnetic Site Survey (10 kHz
to 10 GHz)

475-2000
Standard

Measurement Procedure for Field-
Disturbance Sensors, 300 MHz to
40 GHz.

1140-1994
(R1999)

Test Procedures for the Measure-
ment of Electric and Magnetic Fields

91

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Standard

from Video Display Terminals
(VDTs) from 5 Hz to 400 kHz

1302-1998
Guide

Electromagnetic Characterization of
Conductive Gaskets in the Frequency
Range of DC to 18 GHz

1309-1996
Standard

Calibration of Electromagnetic Field
Sensors and Probes Excluding An-
tennas from 9 kHz to 40 GHz

P1530
Recommended
Practice

Design and Construction of Calibra-
tion Artifacts for Cable and Connec-
tor Shielding Test Fixtures for
Frequencies from 1 Hz to 10 GHz

P1560
Standard

Methods of Measurement of Radio
Frequency Interference Filter Sup-
pression Capability in the Range of
100 Hz to 40 GHz

P1597.1
Standard

Validation of Computational Elec-
tromagnetics (CEM) Computer
Modeling and Simulation

IEEE P1597.2
Recommended
Practice

IEEE for Computational Electro-
magnetics (CEM) Computer Model-
ing and Simulation Applications

IEEE P1642
Recommended

Practice

Protecting Public Accessible Com-
puter Systems from Intentional EMI

Note: P indicates project underway and is not yet a stan-
dard.

There were many more clarifications that can be further

summarized in reference [27]

History of standards of the ANSI Accredited Stan-

dards Committee C63 (EMC)

Reference [26] contains an excellent summary of US

EMC standards history, which dates back, primarily to the
early 1940’s when there was issued in 1940 a series of
reports, entitled: “Methods of Measuring Radio Noise”.
These reports were developed by a joint coordinating
committee (JCC) on radio reception between the Edison
Electric Institute, the National Electrical Manufacturers
Association and the Radio Manufacturers Association. At
this time the emphasis was to gather date on radio noise
levels to serve as the basis for setting noise limits.

In 1944, the JCC became a Sectional Committee C63

under the American Standards Association which later
became the American National Standards Institute, with a
scope covering Radio-Electrical Coordination. After
WWII, C63 published its first standards: C63.1 on the
subject of noise instrumentation specifications in the
range 150 kHz to 20 MHz which was followed soon af-
terwards in 1950 by the first edition of C63.2 which pro-
vided specifications for radio noise measurement
instrumentation. [26] Moving onto the 1950’s and 1960’s
much EMC work focused on application to military EMC
measurements. ANSI C63.3 covered instrumentation for
measuring emissions between 20 and 1000 MHz. These
instrumentations used peak detectors rather than the more

common quasi-peak detectors found in IEC/CISPR docu-
ments even to this day.

ANSI C63.4 covering the method of measurement of

radio noise emissions first appeared in 1963 covering
measurement methods of radio noise voltage and field
strengths in the frequency range 150 kHz to 25 MHz. In
1981, this standard had a major revision to incorporate
newer instrumentation and broader frequency ranges.
The next edition in 1988 included a mechanism to show
validate test sites, which was needed to resolve the prob-
lems of lack of repeatability of results from test site to test
site. This edition introduced for the first time the concept
of site attenuation as the means to determine site irregu-
larities, test instrumentation calibration inadequacies and
differences in tester approaches to determine site suitabil-
ity. Heretofore these factors led to different test results
for the same product measured at multiple test sites,
which of course was highly undesirable. A list of com-
panion standards was also introduced at the same time to
aid in validating the radiated emission test site. These
included ANSI C63.5 on receiving antenna calibration,
ANSI C63.6 on the computation of errors in open area
test site measurements, and finally, C63.7 which gave
guidance on constructing open are test sites for perform-
ing radiated emission measurements as well as site valida-
tion measurements. All four of these standards were
approved for publication on the same day in June 1988
which was a watershed day for introducing major docu-
ments to increase the accuracy and quality of radiated
emission measurements.

Based on the experience using the ANSI series of stan-

dards described in the previous paragraph, improvements
were made to these standards throughout the 1990’s and
into this century. Notably was the 1991 version of C63.4
which for the first time added much details on test setups
for complex systems to increase repeatability as well as
reproducibility of emission testing. It also increased the
frequency range to cover 9 kHz to 40 GHz. This was a
significant event as the previous standards covered only
up to 1 GHz. Specific measurement procedures were now
identified for four types of products:

a.

Information Technology Equipment

b.

Intentional radiator

c.

Unintentional radiators

d.

Periodic intentional radiators.

Only the details for ITE equipment were included with

the other product classes under consideration. The 1992
version of the standard picked up measurement methods
for testing intentional radiators as well as unintentional
radiators other than ITE. Periodic intentional radiators
were considered part of the intentional radiator scheme
and hence that class was absorbed into the measurement
methods for intentional radiators, whether operating con-
tinuously or periodically. In the next 10 years there were
two more amendments that culminated in the 2003 edition
of C63.4 which is presently the one referenced by the
FCC for performing compliance testing for ITE, and a
significant percentage of, but not all intentional and unin-
tentional radiating devices covered by their Rules. It is

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interesting to note that the 2001 edition included for the
first time the use of wideband TEM devices for a small
class of products which fit within the device as an alterna-
tive to making emission measurements at an open area
test site or equivalent. In addition where possible, the
standard also changed to harmonize where possible with
the work of CISPR and its CISPR 22 document which
itself was based on earlier versions of C63.4.

The present 2003 edition added useful information that

has the potential to reduce test time and complexity as
well as clarified several points that users had presented to
the committee. [27] The changes included:

a.

Clarification that the text takes precedence of the
test setup figures which are only examples for guid-
ance

b.

Allowing the use of spectrum analyzers that do not
fully meet CISPR 16 or ANSI C63.2 specifications
but in case of dispute, such instruments fully meet-
ing these two specifications must be used.

c.

Clarification of required test equipment calibration
intervals

d.

Identifying how to test power packs which convert
AC to DC which is then used by many products
such as laptop computers

e.

Providing a method for looping back cables be-
tween input and output ports of large floor standing
equipment eliminating the need in some cases to be
connected to other equipment in a typical installa-
tion

f.

Warning that exploratory testing in a chamber that
does not meet the normalized site attenuation re-
quirements is not a substitute for full spectrum test-
ing at a site that does meet NSA requirements.

g.

Clarification of test frequencies to be used during
intentional radiator testing.

We now return to the activities in the 1980’s. In 1984

the first of the next core of standards was published.
ANSI C63.12 is the first and only C63 standard that has
recommended limits. The first edition was in 1984
quickly followed by the 1987 version with international
standards updates at the time. It contained graphs of
man-made radio noise power and field strengths near the
surface of the earth for rural, residential and business
areas based on data taken decades before. It also con-
tained guidance on allocation of radiated and conducted
emissions from components of a large system or product
based on the number of components in the system and
emission shielding attributes within the system lineup or
the allocation of power used by the components. Radiated
immunity test levels were also suggested. Further
changes in international and military immunity techniques
and requirements prompted the 1999 edition.

In 1991, ANSI C63.13 was published to meet the need

for guidance in the basic understanding of EMI power-
line filters. This document is still applicable as it pro-
vides insight on the difficulties in specifying technical
characteristics of such filters not being measured at full
power load and actual impedances of the product which is
connected to it and hence the differences among manufac-
turers data application. In 1993, C63 published its ESD

guidance document with the intention to harmonize with
the IEC 801-2 document at that time. The ANSI guide
provides test techniques for furniture discharge, statistical
determination of the number of ESD pulses per test point
to be applied, a confidence level that the discharge is
applied at critical times in the product activity cycle, and
a better ESD waveform as they have been found to occur
in equipment installations. This guide is under revision as
of the writing. In 1998, ANSI C63.17 was published to
meet the EMC test and operational etiquette requirements
in the FCC Part 15, Code of Federal Regulation for the
new unlicensed personal communications services in the
frequency range just below 2 GHz. This service lan-
guished until recently when the frequency allocations
were amended to allow better use of the spectrum.

The period 1997 through 2001 brought forward several

specialty standards for ASC C63. C63.18 was the first
standard devoted to in-situ immunity measurements of
medical equipment using typical transceivers (portable
transmitters) found in hospital environments such as mo-
bile phones, pagers, walkie-talkies, etc. This recom-
mended practice has been successfully applied in
determining separation distances for such transceivers to
be away from medical devices such that there is no criti-
cal performance degradation of these devices. Next,
C63.14 was published in 1998 as a replacement for MIL-
STD-463 and hence contained both military as well as
non-military EMC definitions. Since it was also used by
the military, there were definitions added to cover elec-
tromagnetic pulse (EMP) for example. The dictionary is
being updated as of this writing to cover the definitions in
all of the C63 standards and hence limit repeating them in
each standard as they can now be referenced in the source
C63.14 standard dictionary. ANSI C63.19 was published
in 2001 and is now referenced by the FCC for determin-
ing the EMC between mobile (cellular) phones (wireless
communications devices) and hearing aids. This work
represented collaboration among mobile phone manufac-
turers, hearing aid manufacturers, users of hearing aids,
and the EMC standards community represented by ASC
C63.

Table 2: ANSI ASC C63 Standards

ASA C63.1-1946

Standard [28]

American War Standard for Radio
Noise measuring instrumentation in
the range 150 kHz to 20 MHz

C63.2-1996
Standard

Electromagnetic Noise and Field
Strength, 10 kHz to 40 GHz Specifi-
cations

ASA C63.3-1952
Spec. Standard

Measuring instrumentation in the
range 20 to 1000 MHz.

C63.4-2003
Standard

Methods of Measurement of Radio-
Noise Emissions from Low-Voltage
Electrical and Electronic Equipment
in the Range of 9 kHz to 40 GHz

C63.5-1998
Standard

Calibration of Antennas Used for
Radiated Emission Measurements in
Electro Magnetic Interference

C63.6-1996

Computation of Errors in Open-Area

93

background image

Guide

Test Site Measurements

C63.7-1992
Standard

Construction of Open-Area Test
Sites for Performing Radiated Emis-
sion Measurements

C63.12-1999
Rec. Practice

Electromagnetic Compatibility Lim-
its

C63.13-1991
Guide

Application and Evaluation of EMI
Power Line Filters for Commercial
Use

C63.14-1998
Dictionary

Technologies of Electromagnetic
Compatibility (EMC), Electromag-
netic Pulse (EMP), and Electrostatic
Discharge (ESD) (Dictionary of
EMC/EMP/ESD Terms and Defini-
tions)

C63.16-1993
Guide

Electrostatic Discharge Test Meth-
odologies and Criteria for Electronic
Equipment

C63.17-1998
Standard

Methods of Measurement of the
Electromagnetic and Operational
Compatibility of Unlicensed Per-
sonal Communications Services

(UPCS) Devices

C63.18-1997
Recommended
Practice

On-site Ad Hoc Test Method for
Estimating Radiated Electromagnetic
Immunity of Medical Devices to
Specific Radio-Frequency Transmit-
ters

C63.19-2001
Standard

Methods of Measurement of Com-
patibility between Wireless Commu-
nication Devices and Hearing Aids

IV. C

ONCLUSION

This paper has provided an overview of the EMC regula-
tory and standards activity in Europe. It has also high-
lighted some major activity in the United States. The
details are contained in the references which compliment
this paper and give authoritative background information.

A

CKNOWLEDGEMENT

The authors would like to thank those colleagues who
have provided invaluable inputs for the paper. Their
contributions are highlighted in papers they have written
as noted in the references section. For more detailed
information about their contributions, the authors suggest
that the reader investigate the many references cited in
this paper.

R

EFERENCES

[1] Reichsgesetzblatt No. 21 „Gesetz über das Telegraphenwesen des

Deutschen Reiches“ from 6 April 1892

[2] Meyer’s Lexikon (Dictionary), ed. 1928: “Rundfunk” (broadcast-

ing)

[3] Seelemann, F.: “Funk-Entstörung” (radio interference suppression),

Otto-Elsner-Verlag 1954, available from Technische Informations-
bibliothek (TIB) Hannover, Germany.

[4] Mueller, K.-O.: “Procedures for Granting Licenses for the Opera-

tion of RF Devices, Radio and TV Receivers in Western Ger-
many”, 1987 by Rohde & Schwarz

[5] Private communication of the author with Dr. Jasper Goedbloed
[6] Private communication of the author with Prof. Ryszard Struzak,

now Switzerland, and Mr. Wladyslaw Moron, Poland

[7] Private communication of the author with Dr. Knopf, head until

1992 of the GDR Radio Interference Department in Kolberg of the
Central Institute for Posts and Telecommunications (RFZ) and Mr.
Lutz Dunker, RegTP.

[8] Private communication of the author with Prof. Ermanno Nano,

Italy

[9] Minutes of the first meeting of the CISPR 1934
[10]Stumpers, F.L.H.M.: “International Co-operation in the Suppres-

sion of Radio Interference – The Work of C.I.S.P.R., Proc. I.RE.E.
Australia, Febr. 1971

[11] Jackson, G.A.: “International EMC Cooperation Past, Present and

Future”, IEEE AES Magazine, April 1987

[12] Jackson, G.A.: “The early history of radio interference”, Journal of

the IERE Vol. 57 No. 6 pp.244 -250 (1987)

[13] CISPR/IEC77 Joint Meeting 1999 in San Diego (US-NC docu-

mentation): “The History of the IEC/CISPR and The IEC Techni-
cal Committee TC77”, provided by D. Moehr.

[14] ISO EMC standards on Automotive Immunity tests
[15] ETSI EMC standards
[16] European EMC Directive 89/336/EEC of 9 May 1989
[17] Draft New European EMC Directive
[18] Automotive EMC Directive 2004/104/EC
[19] CISPR Report No. 31 (Stresa 1967), with references of the Re-

ports from the Res. Inst. of Telecommunications (VUS) Prague
No. 339/1961.

[20] Meyer de Stadelhofen, J.; Bersier, R.: „Die absorbierende Mess-

zange – eine neue Methode zur Messung von Störungen im Me-
terwellenbereich.“ Techn. Mitt. PTT (Schweiz) No. 3, 1969 (engl:
“The absorbing clamp – a new method for the measurement of
disturbances in the range of meter waves”)

[21] Several Swiss Decrees among which the following are mentioned:

Decree of the Department of Post and Railway for the protection
of radio receive stations against radio interference generated by
high and low energy installations of 29, Jan. 1935. Swiss Decree
on EMC of 9 April 1997 (updated on 28 Dec. 2000)

[22] Further material provided by Mr. Heinrich Ryser, Switzerland

Note: References for all the standards cited in this paper are contained

in Tables 1 and 2.

[23] A. Wall, “Historical Perspective of the FCC Rules for Digital

Devices and a Look to the Future”, 2004 IEEE Symposium on
Electromagnetic Compatibility, August 2004.

[24] Notice of Proposed Rule Making—in the Matter of Amendment of

Part 15 to redefine and clarify the rules governing restricted ra-
diation and low power communication devices,
FCC Docket No.
20780, published in the US Federal Register on 16 October 1979 at
44 FR 59530.

[25] D. N. Heirman, “Commercial EMC Standards in the United

States”, Supplement to 10

th

International Zurich Symposium and

Technical Exhibition on Electromagnetic Compatibility, 9-11
March 1993.

[26] R. M. Showers, “Influence of IEC Work on National EMC Stan-

dards”, Supplement to 10

th

International Zurich Symposium and

Technical Exhibition on Electromagnetic Compatibility, 9-11
March 1993.

[27] D. N. Heirman, “EMC Standards Activity”, Spring 2003 issue of

the IEEE EMC Society Newsletter.

[28] Proposed American Standard Specifications for Radio Noise

Meter, 0.015 to 25 Megacycle/Second, March 1950, American
Standards Association.

94


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