Product Certification

This article explains the saga of having electronic products certified for sale.

 

In order to be able to sell a piece of electronic equipment or device in a country, various certifications may be required to be acquired as per the appropriate governing regulations set by that country. Each country may mandate compliance with its own set of standards which would form a large stockpile of documents. However in most cases, such standards are derived from or are variations of a more internationally recognized standard such as the one laid out by the IEC (International Electrotechnical Commission). An example is the BS EN 55024, a British Standard that lays down the limits and methods of measurement of Immunity characteristics of IT equipment. This standard is derived from the European Standard EN 55024:1998 with the incorporation of amendments A1:2001 and A2:2003.

 

Now, literally there are thousands of standards, each with its own list of variations and amendments. The question is that how do we go about studying them and keeping abreast of the latest additions and modifications. While, for a particular electronic equipment to be developed, it might take some time to identify all required standards mandated by the target countries, studying them might not be as intimidating as it would seem at first. The reason is that most standards serving common purpose are derived from a common ancestor which makes their study easier. At Ascenten, continuous track is kept of the most commonly required standards as they are amended every  year. Standards directly affect the development and their recommendations and limits must be put into effect right at the time of design. Most standard variations are directly advertised by the standard making body or are published in popular electronic magazines.

 

At Ascenten we segregate these standards mumbo jumbo into three categories namely Standards for Safety, Standards for EMC (Electromagnetic Compliance) and Other Standards.

 

More about these at a later note. For now let’s consider the procedure for having a piece of electronic equipment certified for compliance: As soon as first pre-certification prototypes are produced the design engineers take them to a testing agency for testing. There three things are done: first the device is tested for compliance to the specified standards, next if the device fails the engineers recommend design changes that are likely to help during retesting and once the device passes all tests, a test report is generated. Now, if the device fails at the first testing attempt, valuable time may be lost in making design changes, modifying prototypes and resubmitting the same for a new set of tests. Therefore at Ascenten, we have a practice of submitting several prototype variants for tests, especially the EMC tests, which at times may yield rather strange and unpredictable results. That way, if a prototype fails, immediately another prototype could be tested without wasting a day. Depending on the standards and countries involved more than one testing agency may be involved. It is important to make sure that an agency that tests for compliance to a standard for a specific country is accredited by the national standards body of that country. For example, in order to comply with the OSHA Safety Standards a National Accredited Testing Laboratory (NRTL) must approve the device.

 

Once all required test reports are in place the next step is certification. Different regulations have different methods of certification. Certain regulations such as the CE Mark (necessary in the EU countries) do not require manufacturer to obtain a certificate, rather when necessary they require them to produce a Suppliers Declaration of Conformity (SDoC) which is a self declaration and a demonstrable, verifiable fact that the product conforms to all relevant directives and standards as tested by an accredited third party laboratory. In this regards the manufacturer must maintain a file of all relevant test and design documents.

 

On the other hand, an FCC Part 68 approval (in the US) requires the manufacturer to file the SDoC or the Telecommunication Certification Body (TCB) review report with the Administrative Council for Terminal Attachment (ACTA). The ACTA then files the report in a public database of FCC Part 68 approved products and issues a certification number that could be printed on manufacturer’s label as a public declaration of conformance.

 

EMC Compliance is voluntary in Japan and is supervised by Voluntary Control Council for Interference (VCCI) which issues a certification number upon being provided relevant test documents.

 

The certification process is outlined below:

 

Coming back to the standards mumbo jumbo, the three categories are detailed below:

 

1. Standards for Safety

These standards in general are meant to ensure that the product in its functional, non-working or failed state is not likely to directly or indirectly harm persons, animals or objects. Following table details a country wise standards requirement.

 

Country Service

Standard

United States

UL NRTL/C Mark

UL 60950, UL 61010, UL 60065

CSA NRTL/C Mark CSA 60065, UL 60950, CSA 601, CSA 61010,
C22.2 No. 225
UL-C Mark UL 60950, UL 61010, UL 60065

Canada

CSA Mark

CSA 60065, UL/CSA 60950, CSA 601, CSA
61010, C22.2 No. 225

Europe

Self Declaration of
Conformity        (SDoC
)

EN 60950, EN61010, IEC 60065, IEC
60601

Australia

Conformity declared by an Australian
Communications Authority (ACA) accredited agency.

AS/NZS 60950

 

2. Standards for EMC

EMC Stands for Electromagnetic Compliance, every engineer’s true nightmare. Every piece of electronic equipment produces radiation (electromagnetic waves). In addition, a device may also be subjected to external radiation from surrounding electronic equipment. EMC standards put a limit to the amount of radiation allowed out of a device and at the same time specify limits of external radiation in which the device must reliably live and perform. In addition the device must be able to survive various kinds of immunity tests as outlined below:

 

Country

Standard

United States

FCC Part 15

Canada

ICES 003

Australia

AS 3548

Japan

VCCI – V

New Zealand

CISPR 22

Europe

EN 55022, IEC / CISPR 22

Chinese Taipei – Taiwan

CNS 13438

 

European Immunity Standards:

 

Standard

Description

EN 55024

Information technology equipment — Immunity
characteristics — Limits and methods of measurement

CISPR 24

Information Technology Product
Specific

IEC 1000-4-2

Electrostatic Discharge

IEC 1000-4-3

Radiated Immunity

IEC 1000-4-4

Fast Transients

IEC 1000-4-5

Surge Transients

IEC 1000-4-6

Conducted Immunity

IEC 1000-4-8

Power Frequency Magnetic Field

IEC 1000-4-11

Voltage Dips, Short Interruptions and
Voltage Variations

 

Ascenten has good experience designing products for EMC where proper PCB layouts, casing construction and circuit protections play a pivotal role.

 

3. Other Standards

Depending on application of the equipment, other standards may apply. For example, European aftermarket LPG/CNG automotive conversion equipment needs a UNECE Regulation 115 conformance. There are several specific standards for various categories of products like medical devices, life support devices and such.

 

One mandatory standard that is being universally held is RoHS. The Restriction of the use of certain Hazardous Substances (RoHS) restricts six substances in products:

 

1. Lead – (Pb)
2. Mercury – (Hg)
3. Hexavalent chromium – (Cr(VI))
4. Cadmium – (Cd)
5. Polybrominated biphenyl flame retardants – (PBB)
6. Polybrominated diphenyl ether flame retardants – (PBDE)

 

The RoHS directive has been put into effect in the EU nations since July 1, 2006 and all products sold after this date needs to conform to it. RoHS requires a self declaration of conformity (SDoC) but no approvals. However at the end of the day it is the manufacturer’s responsibility to ascertain that his product conforms, either by confiding in the parts used in the product or by having it tested by a third party for the presence of any of the above hazardous substances. For this, normally the design house prepares a file of by obtaining certificates of conformity from individual OEM of every electronic part deployed in a product. In addition, a third party testing is recommended, wherein they onion skin the product peeling it off part by part which are then tested for presence of hazardous substances.

About The Author

Meet Kumar (Founder & Managing Director, Ascenten) is the Chief Design Architect and designs circuits and algorithms. He has deep interest in reliability testing, signal processing, numerical analysis techniques, noise analysis and probability theory. Armed with an MS in Electrical Engineering, Meet brings with him over 13 years of industry experience.

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