EMC & EMI Emissions Measured

How Are EMI and EMC Emissions Measured?

Do you have an electronic device that is being manufactured? Did you know your product needs to be tested for electromagnetic compatibility? This article will explain what happens with this process.

All electronic devices and electric equipment make use of electromagnetic waves produced by electrically charged particles in motion. This electromagnetic radiation travels through the air, empty space, and other substances.

The full range of wavelengths and particles called photons forms the ‘electromagnetic spectrum’.

Regulatory compliances require that electronics undergo electromagnetic testing, a critical step when bringing a new product to the market.

What is EMC and EMI Testing?

Generally speaking, electromagnetic testing should only be performed by a recognised EMC testing body. The testing is grouped into two categories, emissions testing, and immunity testing.

– Emissions Testing

The purpose of emissions testing is to ensure that emissions from the device being tested are below the limits relevant for that type of device.

Basically it measures the amount of electromagnetic ‘noise’ generated during normal operation of the device.

The tests can provide reasonable assurance that the device will not emit harmful interference while operating within its normal operating environment.

– Immunity Testing

The purpose of immunity testing is to ensure that the device will operate as intended within its expected operating environment and how it reacts when exposed to disturbances such as electromagnetic noise from other devices or equipment.

Regulatory compliance requires both types of testing. The most common applications for electromagnetic testing are:

– Medical devices where devices must work together in close proximity without performance being compromised by interference or electromagnetic noise.

– Military or Aerospace devices to meet standards for avionics equipment and other goods.

– Consumer products such as cellular phones, satellite TV dishes, laptops, and microwave ovens to avoid harmful interference in real-world conditions.

What is the Difference Between EMC and EMI Testing?

Both types of testing are vital for electronic product development and companies across the world are required to comply with EMC/EMI limits finalised by standard bodies before launching products to the market for consumer use.

EMC (Electromagnetic Compatibility) and EMI (Electromagnetic Interference) testing are essential to verify the electromagnetic levels mentioned for any manufactured device.

Designers need to consider the specific military or industrial standards required for products under development.

How to Measure EMC and EMI Emissions

An electromagnetic field consists of two components:

– Electric Field or E-Field measured in V/M (volts per metre)
– Magnetic Field or H-field measured in A/m (amps per metre)

These two fields move at right angles to each other.

Emissions are subdivided into Radiated and Conducted Emissions

Radiated Emissions Testing

This test measures the electromagnetic field strength of emissions unintentionally generated by a product, how large they are, and if they comply with emissions limits set for the particular product.

Radiated emissions measurements are done by using a spectrum analyser and/or EMI receiver as well as a suitable measuring antenna.

The frequency band of interest will be scanned in a test lab to detect emissions that are close to the limits. A process called ‘maximisation’ is used to focus on these emissions and quantify the amplitude of their field strength.

Two primary test sites used for this purpose are:

– Open Area Test Sites (OATS)
– Semi Anechoic Chambers

Conducted Emissions Testing

As a device creates electromagnetic energy, a certain amount is conducted into the power supply cord. Test labs measure these emissions to verify that they comply with the specified limits.

A typical conducted emissions test involves one or more LISNs placed between the power source and an EUT (Equipment Under Test) that filter and isolate unwanted RF signals.

LISNs help to minimise external noise, allowing the lab to only measure noise from the EUT device.

Passing EMC/EMI testing will depend on several factors such as a good understanding of the process involved, the skill of the designers, and proper preparation. The estimated failure rate for first-time passes is 50%.

An EMC design review before designing a product or sending a device to an EMC test lab can help check your product against industry-standard best practices and issues that could increase the chances of first-time pass failure.

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.

EMC requirements for electrical goods

Understanding the EMC Requirements for Australia and New Zealand

Do you understand the EMC requirements for electrical goods manufacturers in Australia and New Zealand? If the answer is no, then you need to understand the electromagnetic compliance (EMC) standards. Not sure what this means? Then please continue reading.

The EMC requirements are quite complex, and there are slightly different standards for different parts of the world.

The Australian Communications and Media Authority are in charge of regulating the EMC standards for Australia and those requirements are available as a detailed list known as the AMCA Standards.

These standards are very similar, and indeed in places identical, to the European standards.

What Do Manufacturers Need to Know

For the most part, if a manufacturer produces products which meet the ACMA standards, then that is sufficient for selling products not just in Australia and New Zealand but also in Europe.

It becomes a more complex issue if you want to export products to the United States, Japan or Canada, where the standards can be slightly different, or if you are looking to import products which were designed for other countries.

How EMC Testing Works

EMC testing is intended to ensure that products do not put out too much electromagnetic interference and that if interference is caused by another product, that they ‘accept’ that interference in a safe way.

All electrical products will produce a small amount of interference because of the way that electricity works.

A product that is well designed will produce very little interference, however, and will also be shielded to stop the interference causing problems with other products.

Australian EMC regulations have strict standards for how products should behave, and require that products are tested in an accredited laboratory.

Once the tests are completed then a Declaration of Conformity is produced which will show that the product complies with all applicable standards.

The manufacturer is required to register the product to a national database of accredited/compliant products and also apply a compliance label either to the product itself, to the packaging, or both, depending on the size, power, and nature of the product.

The challenge for manufacturers is making sure that their products meet the correct standards.

There are a lot of different standards, designed for different types of product, and figuring out which ones a specific product should meet can be confusing.

That’s why it is best to consult an accredited EMC testing laboratory when designing your products. They can advise you on what design standards you should be working towards.

Testing covers a few specific classes:

  • Emissions
  • Susceptibility
  • Coupling

Emissions relate to how electromagnetic energy is generated by a product and released into the environment.

Meanwhile, susceptibility relates to how a product might malfunction and how such malfunctions might result in unintended operation. Coupling relates to the way that interference might reach a victim.

The most common EMC test which is used in all countries is the Radiated Emissions Test. This measures the electromagnetic field which is emitted by a product.

These emissions can cause interference to a number of electrical systems, including navigation systems and the landing guidance systems for aircraft.

Because of the risk of such interference causing serious faults, it is vital that all consumer goods on the market pass EMC regulations and do not produce strong-enough emissions to cause problems with sensitive systems.

Indeed, it is the risk of EMC issues which is what leads to airlines asking passengers to switch off all handheld or portable devices.

While it is unlikely that a device would cause interference, the risk is there, especially if a device is malfunctioning.

EMC testing confirms whether a device is generally safe, and also looks at edge-cases, such as how severe interference could be in the event of a malfunction.

If you are unsure whether your product needs to be labelled, or if it meets the EMC requirements at all, then you should seek professional advice to ensure that you are correctly complying with Australian regulations.

At Compliance Engineering, we offer EMC certification and advice and can help with labelling requirements as well as the standards for international certification.

Whether you are working on small, low-risk products or communication technology, we can help you to ensure that your products are fully compliant and that they are ready to be sold in Australia or around the world.

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.

EMC Labelling Requirements

What are the EMC Labelling Requirements in Australia

If you are an electronics manufacturer, do you fully understand the labelling requirements for your products in Australia? If not, then you need to read below to learn more.

The EMC labelling requirements are the requirements set out by the Australian Communications and Media Authority.

The requirements specify how products should be tested and labelled, and also the records that a supplier is required to keep relating to a product and its compliance with EMC standards.

Do You Need to Register as a Supplier?

The EMC requirements can be quite confusing. Before a supplier can put a label on a product, they must register themselves on the national database so that they are listed as a ‘responsible supplier’.

Labelling is not always mandatory. Some devices are classed as being low risk, and in that instance, a label is not required. However, even low-risk devices are required to meet certain standards.

What Are the EMC Standards?

The EMC standards are laid out on the ACMA website. These are the standards that are set by ACMA for products sold in Australia and New Zealand.

If you want to sell your products abroad then you will need to confirm that they are also compliant with other, international standards.

The standards used in Australia and New Zealand are very close to the ones used in the UK and Europe, so for most manufacturers, the only thing that would be required would be some additional tests to ensure all aspects of the international standards are covered.

There may be some regional differences, however, so it is a good idea to seek advice from a qualified test centre.

How Do You Prove Compliance?

If a product has passed EMC testing (electromagnetic compatibility) and is not considered to be a low-risk product, then it must be labelled. The ACMA requires that compliance labels are durable and are printed in a legible format at an appropriate size.

If the product has its own built-in display then the label can be displayed in an electronic form.

Products that were manufactured prior to the 1 March 2016 may bear a C-Tick compliance mark. The C-Tick mark was superseded by the RCM.

Any products which already carry a C-Tick may still be sold, and do not need to be relabelled. However, all new products should bear the RCM.

The compliance mark should be no smaller than 3mm in height and can be any colour as long as it contrasts with the background colour so that it is easy to read.

If the mark is stamped, moulded or engraved then the relief must be prominent enough to make the mark easy to read.

Electronic labelling is permitted for built-in displays (but not displays that are external to a product and must be connected separately).

If an electronic label is used then it should display the information prominently, for example during the power-up sequence, or in the help menu for the device.

The documentation which comes with the product should explain how to view the compliance information. In some cases, it may not be practical to apply a label to a product, perhaps because it is small in size.

In that case, the compliance information must appear both on the external surface of the product’s packaging, and also in the product’s documentation or warranty information.

Any label printed on a product’s packaging must occupy an area which is greater than 1% of the external surface of the package.

The manufacturer must also maintain records that explain why they have chosen not to label the surface of the product and should record the location of the label.

If you are unsure whether your product needs to be labelled, or if it meets the EMC requirements at all, then you should seek professional advice to ensure that you are correctly complying with Australian regulations.

At Compliance Engineering, we offer EMC certification and advice and can help with labelling requirements as well as the standards for international certification.

Whether you are working on small, low-risk products or communication technology, we can help you to ensure that your products are fully compliant and that they are ready to be sold in Australia or around the world.

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.

Choosing EMC Test Lab

How to Choose a Good EMC Test Lab

How important is it to choose a top-quality EMC test lab? The consequences of getting it wrong can be catastrophic not just in terms of costs, but time. Read below for more detail.

If you make electronic or electrical products then you will need to ensure that your products comply with the EMC regulations and that they are correctly labelled also.

For small, low-risk products, the regulations are quite simple but if your product needs to be fully labelled and tested then you should work with a lab to certify it and to document the compliance testing that has been done.

The penalties for improper testing and labelling are quite severe.

This is because the EMC regulations exist to ensure that all electronic appliances are safe and that they will not interfere with essential services such as communications or medical devices.

For this reason, it’s important that you choose an EMC test lab that you can trust.

What to Look for in an EMC Test Lab

EMC testing is a complex field, and there are a number of different standards to worry about, as well as requirements for different products.

In addition, if you plan on selling a product abroad, not just in Australia, then you will need to make sure that in addition to the Australian standards, you also comply with the standards required for other countries.

This includes standards such as the CE mark, the EN Mark, or the FCC requirements. A good lab will do far more than just test your products.

There are some labs out there that will just push the buttons and tick the boxes to tell you whether your product has passed or failed.

Good labs will offer advice and guidance, especially when you’re getting tests done on a prototype so that they can give you advice beyond ‘use some chokes to cut down on interference’.

Depending on the products that you want to get certified, you may need a fairly sophisticated facility. Consider the following:

  • Does the lab have an open area test site?
  • Do they offer pre-compliance testing in a GTEM?
  • Do they have an ESD simulator that can provide high voltage for good testing?
  • What is the lead time on tests?
  • Can the lab certify products for sale internationally?
  • How much do the tests cost?

Shop Around for the Best Prices

Prices for EMC testing can vary massively. There are some Far East labs that are cheap, but the lead times can be incredibly long, and they don’t always have the tools required to perform the full battery of tests.

They may claim that they can offer all the tests you need, but if they are cobbling together tests on less than ideal equipment then you may face problems later on if your product is not fully compliant.

Using a more local lab will give you some peace of mind since you know that it is operating to Australian regulations, and you can be more confident in the standard of the equipment.

It doesn’t whether you’re looking for shock, ingress, impact, vibration, RF shielding or environmental testing, performing the testing in Australia gives you more peace of mind.

For newer products and prototypes, it is often worth paying a little extra for advice and recommendations as you go through the prototyping stage.

It’s better to pay one fee and pass first time, than to have your time to market delayed by doing tests and having to repeatedly go back to the drawing board, pay new fees, and modify the design at a later stage.

At Compliance Engineering, we offer EMC certification and advice and can help with labelling requirements as well as the standards for international certification.

Whether you are working on small, low-risk products or communication technology, we can help you to ensure that your products are fully compliant and that they are ready to be sold in Australia or around the world.

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.