Overview of EMI EMC Testing
EMI is short for Electromagnetic Interference and is an electronic emission interfering with the components, RF systems and most electronic devices. It is the result of man-made or natural occurrences. All electronics must be shielded to protect electronic equipment and components from electromagnetic radiation, and if a device is improperly shielded from EMI, it will not work. Such shielding ensures that electronics remain fully operational and work without any interference. If a component is vulnerable to interference, then it will not work.
Electronic devices generate electrical noise that interrupts cables and wires, causing problems for connected devices. The EMC stands for Electromagnetic compatibility, and it is the term used to describe a device's functioning in an electromagnetic environment.
EMI is for the radiation, and the EMC is merely the ability of a system to operate within the presence of radiation. EMI EMC Testing predicts the product performance in any electromagnetic environment. It also determines the possibility of interference with other equipment degrading performance. It is required to comply with the regulations or for information and product improvement purposes. EMI EMC Testing is basically categorised into testing for emissions and testing for immunity.
Products under EMI EMC Testing
Some of the primary products under the EMI EMC Testing are as follows:
EMI EMC Standards List
Here is the list of common EMI EMC Standards:
Common EMI EMC Standards
SAE, ISO7637, IEC CISPR-25, ISO1145-1, ISO1145-2
MIL-STD-461, DEF STAN 59/411, MIL-STD-704, MIL-STD-1275, MIL-STD-1399
FCC Part 15 class A, EN 61000-6-4 (generic), EN 61000-6-2(generic)
FCC Part 15 class B, EN 61000-6-3 (generic), EN 61000-6-1(generic)
Switchgear and control
Power station and substation
IEC TS 61000-6-5
Process control and measurement
Benefits of EMI EMC Testing
Following are the benefits of EMI EMC Testing:
It ensures the safety of users and operators of any electronic products.
It tests whether products meet the required objectives within the given environment.
- Regulations and standards
This testing is mandatory from a regulatory perspective. Applicability is determined by the manufacturer, manufacturer's location, consumers or the organisation/industry.
Book a Free Consultation
Get response within 24 hours
Procedure for EMI EMC Testing
Tests that are included under EMI EMC testing are as follows:
The stages involved in the EMI EMC testing are as follows:
- Development Test
This test ensures that the best possible EMI EMC performance is obtained. It is easier to make changes at this stage, and any filters, circuit layout, screening and other aspects of design are easily changed at this stage.
- Pre-Compliance Test
It is done once a representative working model of the final equipment is available. Testing is generally performed at the development lab as part of the product testing programme. The main purpose of such a test is to check the performance of the complete product.
- EMI EMC Compliance Test
When the product development is complete, it is necessary to undertake a full run of the EMI EMC compliance testing. This ensures that the product meets all the requirements with respect to the standards it needs to meet. The basic nature of the test depends on the product but needs to be sufficient to ensure that the product conforms to the EMI EMC standards.
- Production Test
The main EMI EMC testing enables the product to be sold. However, there is an obligation on the manufacturer to ensure that the product meets the stated performance. In any production process, there are small changes as the supplied components change. This has an effect on the EMI EMC test performance, and therefore, it is an obligation of the manufacturer to perform some tests.
Frequently Asked Questions
EMS stands for Electromagnetic susceptibility, which describes how a device is itself affected by the disturbances coming from the environment.
The agencies that are dealing with the EMI EMC Testing are the Institute of Electrical and Electronics Engineers (IEEE) and International Electrotechnical Commission (IEC).
The testing required for EMI EMC compliance falls into the following categories:
- Conducted emissions
- Radiated emissions
- Conducted immunity
- Radiated immunity
- ESD immunity
- Transient immunity
- Surge immunity
The different types of EMI are as follows:
- Conducted EMI
- Common Mode EMI
- Differential Mode EMI
- Radiated EMI
Conducted emission is a process of coupling electromagnetic energy from a device to its power cord.
This test involves measuring the EMI in the air, which is generated unintentionally by the device under test, and as it travels through air, thus it is called radiated emission.
OATS stands for the Open Area Test Site, which is the most common radiated emission test site.