Guide to Electromagnetic Compatibility (EMC) Testing Methods

Guide to Electromagnetic Compatibility (EMC) Testing Methods

Guide to Electromagnetic Compatibility Testing

Electrical products often interfere with other electronic devices or get interfered with by other gadgets within the same platform.

Electromagnetic compatibility (EMC) testing is done to ensure that electrical devices don’t interfere with each other, and they co-exist peacefully within that environment.

There are two main categories of EMC testing that you should know about:

  1. Emissions

The electromagnetic interference and disturbances emanating from electronic devices can cause other electronic gadgets to potentially malfunction.

This is more so if the electronic devices co-exist in the same environment.

The emissions part of the testing covers this in the EMC testing and certification process.

This stage is better known as EMI or Electromagnetic Interference.

  1. Susceptibility and immunity

Immunity of the electronic device is its ability to withstand the interferences and work normally without affecting or getting affected by other electronic products.

The emissions of other devices shouldn’t affect the device that is undergoing the EMC test.

Susceptibility, on the other hand, is the opposite of immunity. It tests if the device is less immune to other electromagnetic interferences.

Less electromagnetic interference value means the device is more susceptible.

Immunity testing is often not required on commercial electronic products meant for sale in Australia.

EMC emissions

Electromagnetic fields contain two primary components: the electric field and the magnetic field. This test is categorised into two parts:

  1. Radiated emissions

In this test, the magnetic components of the electromagnetic waves use a spectrum analyser, a measuring antenna, and an EMI receiver.

The testing unit uses a particular antenna known as the Van Veen Loop that measures the magnetic field emissions of the electronic gadget on three different axis.

  1. Conducted emissions

These are the electronic interferences that start from the various frequencies generated by the electrical device.

The emissions from the gadgets can either be continuous meaning they emit at a specific frequency or non-continuous where the rate of emission varies from time to time.

EMC immunity

The EMC immunity test is often transient or continuous depending on the type of electrical product.

Transient tests are done on gadgets that may involve sudden outbursts of energy while continuous testing applies to devices that stimulate RF proximity.

Some of the common tests involved in continuous immunity testing are conducted immunity, radiated immunity, and power-frequency magnetic field community.

The transient immunity testing includes electrical fast transient burst, electrostatic discharge, surges, short interruptions, voltage variations, voltage dips, and pulsated magnetic field.

However, before you send your product for EMC testing, you need to know which particular test applies to what devices.

You can get in touch with a NATA accredited laboratory that performs detailed EMC testing.

Many advanced laboratories in Australia are now equipped with the latest tools and machines to perform these tests.

These facilities cater to a broad range of certification requirements such as EMC Compliance Testing, Vibration Shock Testing, EMC certification, Impact Testing (IK Testing), Ingress Protection (IP) Testing, and Magnetic (EMF) Shielding.

Ideally, you should keep the EMC requirements in mind before you start the design process of the gadget to help avoid failing the test the first time around.

If you need EMC testing done, then look no further than Compliance Engineering.

We are the definitive source for all of your Electromagnetic Compatibility (EMC) requirements.

Please call us today on + 61 3 9763 3079 or contact us through our website here

Why 50% of EMC Testing Fails

Why 50% of Products Fail EMC Testing the First Time

According to electromagnetic computability testing experts, almost 50% of electronic products don’t meet the EMC requirements when they are first tested.

There are many reasons that lead to this failure, and manufacturers and designers are trying their best to improve the success rate.

However, the growing awareness of this problem has made product manufacturers and designers more cautious about the use of EMC software, better EMC design considerations, and reduced circuit dimensions.

The reasons for EMC testing failures

Over the last few years, experts have looked into the rising percentages of products failing EMC testing the first time.

While a few of the electrical products meet the EMC objectives partially, many don’t follow them at all.

For example, medical products are slightly more successful than other products. They have an initial failure rate of 40%.

There may be two factors contributing to this small success: one, they are more conservatively designed, and second, the product standards allow justified derogations from the required limits.

There are five critical reasons why electrical products fail their initial EMC testing.

They fail to apply EMC principles.

All the products lack the knowledge of the EMC principles.

There are unpredicted interactions among several circuit elements.

There are widespread applications of incorrect EMC regulations.

Most of the products incorporate non-compliant modules. Some even use subassemblies in the final product.

Better EMC testing

Many manufacturers claim that EMC testing machines don’t operate to the best extent, and that is the sole reason why their products fail to pass the test the first time.

You can eliminate this problem by getting the products tested from some of the best EMC testers in the industry.

They have advanced test laboratories with a wide range of tools to check the products.

The advanced tools cater to a broader range of certification requirements that include vibration, temperature, shock, environmental, impact, and ingress.

Before searching for a company that offers the best EMC testing, you need to check if they provide the following services:

CE testing

Radio testing

C-tick and RCM testing

Automotive EMC testing

Military and aeronautic EMC testing

Railway and train testing

Interference investigation

Radiation hazard management

RF Shielded Enclosure Manufacturing

Magnetic (EMF) Shielding

Ingress Protection (IP) Testing

Impact Testing (IK Testing)

Vibration Shock Testing

Manufacturers should consider EMC at the initial stages of designing the process.

EMC test operators believe that electrical products fail to comply with the EMC principles because the manufacturers don’t pay enough attention to the requirements during the designing process.

Once you focus on the EMC goals before the designing starts, the product will automatically follow all the necessary points on the checklist as the development process starts.

Every product should consider a few EMC requirements before testing such as target specifications, system architecture, design rules, and regulatory evaluation.

If the product follows these targets, it may pass the EMC testing in its first attempt, and the 50% failure rate will go down significantly.

If you need EMC testing done, then look no further than Compliance Engineering.

We are the definitive source for all of your Electromagnetic Compatibility (EMC) requirements.

Please call us today on + 61 3 9763 3079 or contact us here

 

What are the EMC Standards?

What are the EMC Standards?

Electricity is a vital part of modern life. Unfortunately, electricity creates something known as an ‘electromagnetic field’. 

 

This means that electrical devices can sometimes interfere with each other. 

 

Have you ever heard buzzing just before your phone rings, or seen your TV screen flicker slightly when someone is using a high-powered drill nearby? 

 

These are all signs of electromagnetic interference.

 

Today, those issues are rare compared to how often you might have seen them even a decade ago, but they do sometimes happen. 

 

The reason that they happen a lot less often these days is that the International Electrotechnical Commission has set out standards to help reduce interference. 

 

These standards are known as the EMC Standards.

 

EMC and Safety

 

EMC is important because it relates to the safe operation of a range of electrical devices. 

 

Having your phone interfere with your TV, or your hairdryer cause problems with your game console are annoying, but not a serious issue. 

 

Having a high powered drill interfere with someone’s pacemaker, or a mobile phone interfere with life-saving hospital equipment is a much more serious matter.

 

Understanding the EMC Standards

 

The EMC standards are designed to limit the interference that an appliance can produce. Interference can come from many sources. 

 

Drills and motorcycle engines can cause radio interference, while other appliances can cause interference because of the way that their power supply works. 

 

They draw ‘harmonic’ currents off the mains, and this can cause electrical failures.

 

The EMC Standards are designed to reduce the emissions that appliances produce.

 

This also helps to keep the immunity to interference relatively high so that there is a good margin for safety in the event that things do go wrong.

 

Do All Products Need EMC Testing?

 

If you have a product which contains electrical or electronic parts, then there is a very high chance that it will need EMC testing. 

 

There are some exceptions, however. These are particularly niche product families or products that are already covered by other regulations, such as radio equipment. 

 

It is safe to assume that if you are designing an electronic product it will need EMC testing at the very least. 

 

The regulations for equipment which emits a signal are even more strict than the regulations for other electronic devices or devices which contain electrical components.

 

How EMC Affects You

 

If you are designing or manufacturing electronic products, then you are obliged to make sure that your products meet the relevant EMC standards.  

 

There are a few major international standards. The CISPR (Comite International Special des Perturbations Radioelecrique) is one such standard, and the IEC is another. 

 

If you wish to sell your products internationally then you should check that they meet the standards for the countries that you will be targeting.

 

The standards are reviewed and updated once every five years, on average, and it is important that you check to make sure that your products are still being made in compliance with the latest requirements for both resistance and production of interference.

 

You should have your products tested to confirm that they are compliant. 

 

It is not uncommon for new products to fail the EMC tests the first time they are submitted, and failure can necessitate a redesign of the product, which could delay it entering the wider market.  

 

Talking to the test lab before you submit the product, and taking the time to understand the regulations, will stand you in good stead when you are getting ready to launch. 

 

If you would like to know more about the EMC standards and product testing or need EMC testing done, then look no further than Compliance Engineering.

 

We are the definitive source for all of your Electromagnetic Compatibility (EMC) requirements.

EMC Testing graph

EMC Testing Procedures And Standards

Are you planning to manufacture any sort of electronic equipment? Are you aware of the compliance testing required before your product hits the shelves? Read below for more detail.

Regulatory bodies worldwide have placed certain limits on the levels of emissions electronic and electrical products are allowed to generate.

Electromagnetic Compatibility Testing (EMC) is intended to ensure that electronic and electrical devices do not emit large amounts of radiated and conducted emissions.

When this happens, it is known as electromagnetic interference. EMC testing ensures that the particular device will continue to function as intended when exposed to several electromagnetic phenomena.

In some areas and for some product types, electromagnetic immunity testing is also mandatory.

In order to determine the applicability of emissions and immunity testing for a particular product, it is necessary to determine exactly which standards apply to a particular product.

Why is EMC Testing Important?

With very few exceptions, companies that design, manufacture or import products that contain electronics need to understand Electromagnetic Compatibility for the following reasons:

Protecting the Electromagnetic Spectrum

Only a finite amount of the electromagnetic spectrum is available for use by a large number of products such as x-ray machines, microwave communications, and radio transmissions to name a few.

Unfortunately, many electronic devices without transmitters still emit electromagnetic radiation as a simple by-product of switching voltage and currents inherent in electronic circuitry.

Without limiting the amount of unintended electromagnetic radiation from these electronic devices, the electromagnetic spectrum may be adversely affected.

In addition, frequency bands that are reserved for radio transmissions may also be compromised.

Protection of the electromagnetic spectrum is critical to ensure that in the future electronic devices will continue to operate properly.

Safety

Internally and externally generated EMC phenomena can easily affect the performance and function of an electronic device.

A noisy internal power supply regulation, for example, could adversely affect the sensitive analogue measurements in sensor products or lower the performance of the radio transmitter in wireless products.

Externally generated EMC phenomena can be the cause of data corruption, affect measurement accuracy and RF performance, and cause ICs to fry.

EMC testing can verify that the device will function as expected when subjected to a typical EMC environment.

It may also assist in reducing the number of returns due to poor EMC performance.

Non-compliance Fines

Fines and actions for being caught marketing a non-compliant device can vary from insignificant to downright horrendous.

There are several risk areas related to non-compliant devices that cover both criminal and civil law.

Competitors are likely to notify the authorities of suspected non-compliance or customers may complain when they experience interference with other devices.

A summary of the legal proceedings of the FCC over the past few years revealed that most fines were related to wireless transmitter issues rather than issues with unintentional radiation.

The History of EMC Testing

Although EMC testing can be a burden to small as well as large manufacturers who sometimes find its effectiveness questionable, the rules emerged as a result of real problems.

This led to the government and private sector accommodating and enforcing these rules.

The first EMC regulations were formed in Europe at the turn of the 20th century in response to specific issues that arose from the use of electronic devices.

The first EMC legislation in Europe was “The Lighting Clauses Act” of 1899.

This was enacted in England to curb the problem of flickering lights which was actually caused by defective electric lights.

As a result of discovering that communications cables were capable of negatively affecting each other, the “Law of the Telegraph in the German Empire” was enacted in Germany in 1938.

This was introduced to deal with the influences of EMC disturbances on installations and products in the field of telegraph communications.

Since 1938 the FCC has placed limits on transmitter emissions and continued to expand the rules in response to an explosion on the market of electronic devices and transmitters.

In 1989 the FCC standardised their emission limits for general applications. In 1992 the EMC directive was introduced in the EU.

It was designed to standardise emission requirements and free up the movement of electronic goods across EU member countries.

There is a concerted effort, led primarily by the International Electrotechnical Commission (IEC) to standardise EMC testing requirements throughout the world.

In Europe, emissions and immunity testing are mandated while in some countries like Canada and the United States, only emissions testing is currently required – unless a product falls under an industry-specific category that requires immunity testing as well.

If you would like to know more about the EMC standards and product testing or need EMC testing done, then look no further than Compliance Engineering.

We are the definitive source for all of your Electromagnetic Compatibility (EMC) requirements. Please call us today on + 61 3 9763 3079 or contact us here