EMC
EMC is about making sure a product can work alongside the electronics around it. It must not emit unacceptable electromagnetic noise, and at the same time it has to withstand interference from outside. At Move we build EMC into the design from the start and test early enough for problems to be solved before they become expensive.
EMC
EMC built in from the first schematic
EMC, Electromagnetic Compatibility, is a central part of developing and certifying electronic products. The basic principle is simple: the product must not disturb other equipment around it, and it must itself work correctly when exposed to electromagnetic noise.
From the start
Schematic, PCB layout and mechanics
Emission and immunity
Both sides of EMC
Pre-compliance
Troubleshooting before the formal process
Existing products
Including ones we did not develop ourselves
The EMC Directive sets the framework
In the EU, this is the very purpose of the EMC Directive 2014/30/EU. It sets requirements for both the product's emissions and its immunity to electromagnetic disturbances.
Good EMC therefore does not start in the test laboratory. It starts with the schematic and the PCB layout.
Control of currents and interfaces
A robust design calls for control over return currents, ground planes, decoupling, switch-mode power supplies, high-speed signals and the connections going into and out of the product, among other things. External interfaces such as Ethernet, USB, long cables and the 230 V supply are typical places where electromagnetic energy can either escape or get in.
Filters, protection and shielding
This may call for, for example, common-mode chokes, ferrites, LC filters, TVS protection, correctly terminated signals, filtering on supplies and a well-thought-out connection between the PCB, the enclosure and any shield. On Ethernet, the magnetics, connector and PCB layout can make a big difference. On a 230 V input, both differential-mode and common-mode noise have to be handled, while respecting the requirements for safety and isolation.
EMC is a property of the whole system
Good EMC design, however, is rarely just about adding more filters. Filtering, layout and mechanical design have to fit together. A poorly placed filter can have very limited effect, and a cable shield does not necessarily help if it is terminated incorrectly. That is why EMC has to be seen as a property of the whole system.
Immunity is the other side
Immunity is the other side of the problem. A product can itself be sensitive to, for example, ESD, radiated RF, EFT/burst or surge. Depending on the product type and the relevant standards, tests from the IEC 61000-4 series may form part of the assessment. This matters because EMC problems do not always result in a total breakdown. They can show up as sporadic resets, incorrect sensor readings, lost data packets or communication errors that only occur under particular conditions.
Problems found early in our own lab
At Move we try to detect problems of this kind as early as possible. We can carry out initial investigations and measurements in our own lab and use them to identify obvious problem areas before the product is sent on to external test facilities.
The right test facility for the purpose
We then choose the test facility according to the purpose. A development laboratory or a non-accredited EMC lab can be an effective and relatively inexpensive way to carry out pre-compliance measurements and troubleshooting. There you can work quickly, change filters, move components and repeat measurements without paying for a full formal certification process.
Once the product is mature enough, it can be sent to the relevant formal test laboratory. We have experience working with both pre-compliance laboratories and accredited test houses, and we help choose the right partner for the specific task. The goal is to use the expensive, formal test facilities at the point when the likelihood of passing is high.
CE does not always require a notified body
It is worth noting that CE marking under the EMC Directive does not automatically mean that the product has to be certified by a notified body. The manufacturer is responsible for the conformity assessment, the technical documentation and the EU Declaration of Conformity, and harmonised standards are often used as the basis for documenting conformity.
Help with existing products
We also help with existing products that we did not develop ourselves. If a product fails an EMC test or has problems in the field, we can analyse emission sources and coupling paths and try to solve the problem with as few design changes as possible. That may mean changes to filters, grounding, layout, cabling, firmware or mechanical shielding.
Requirements vary between markets
Finally, it is worth remembering that EMC requirements vary between markets. The EU has the EMC Directive and the relevant harmonised standards, while the USA, for example, regulates many digital products through FCC Part 15. That is why the markets the product is going to be sold in should be considered early in development.
Frequently asked questions
What does EMC mean?
EMC stands for Electromagnetic Compatibility. It means that an electronic product must both limit its own electromagnetic noise and be able to work while exposed to electromagnetic noise from outside.
When should EMC be considered?
From the start. PCB layout, power supply, cables, connectors, filters, enclosure and grounding all affect the product's EMC properties.
Can you do EMC testing in-house?
We can carry out initial measurements and troubleshooting in our own lab. For more extensive pre-compliance and formal testing, we work with external EMC laboratories.
Do you always have to go straight to an accredited laboratory?
No. Early in development, internal measurements or a pre-compliance lab can often be more effective. Once the biggest problems are solved, you move on to the formal test process, if it is required.
Can you help with a product that fails an EMC test?
Yes. We can analyse products we did not develop ourselves, identify likely noise sources and coupling paths, and work towards a solution with as few design changes as possible.
Are EMC requirements the same all over the world?
No. Requirements, standards and approval processes vary between markets. That is why it is important to know early where the product is going to be sold.
Shall we turn your idea into reality?
Technical development takes more than good ideas — it takes the right skills. We have gathered hardware, software and engineering expertise under one roof, so you get from prototype to production quickly and safely.
Reach out to us →