What is Electromagnetic Susceptibility?

Electromagnetic Susceptibility (EMS) refers to a device’s ability to function correctly in the presence of electromagnetic interference (EMI). It is the opposite of electromagnetic immunity, which indicates a device’s ability to resist EMI. Devices with low EMS are more vulnerable to disturbances, which may cause malfunctions or data errors. Therefore, EMS plays a crucial role in the design and certification of electronics. In particular, it is essential in environments with high levels of EMI. Standards and tests are used to ensure equipment meets acceptable EMS levels for reliable operation.

Here a few EMS Certifications:

1. EN 55024
   • Protection against electrostatic discharge (ESD), radio frequency (RF) fields, electrical fast transients (EFT), surges, and other disturbances.
2. EN 55035 / BS EN 55035
   • Sets requirements for equipment to withstand various EMI disturbances in both commercial and residential environments.
3. EN 61000-4-2 (ESD)
   • Tests how well a device can withstand static charges, typically from human contact or environmental conditions.
4. EN 61000-4-3 (RS)
   • Evaluates how equipment behaves when exposed to radio frequency fields, such as those generated by mobile phones, broadcast towers, or other RF sources.
5. EN 61000-4-4 (Burst)
   • Evaluates the ability of a device to resist these short-term bursts.
6. EN 61000-4-5 (Surge)
   • Sets the thresholds for the amount of surge a device can handle without malfunctioning.
7. EN 61000-4-6 (CS)
   • Evaluates equipment’s ability to function in environments where conducted interference is present.
8. EN 61000-4-6 (CS): Level 3
   • Ensuring the device can endure more severe disturbances through cables without malfunctioning.
9. EN 61000-4-8 (PFMF)
   • Evaluates how well equipment functions when exposed to low-frequency electromagnetic fields that occur in the environment, such as those from power lines.
10. EN 61000-6-2 / BS EN 61000-6-2
    • Ensures that equipment used in industrial environments complies with immunity to electrical and electromagnetic interference.
11. IEC 61000-4-2 (ESD): Level 3
    • Specifies immunity to electrostatic discharge, with Level 3 indicating a higher immunity level
12. IEC 61000-4-3 (RS): Level 3
    • Specifies immunity to radiated RF electromagnetic fields. Level 3 indicates a high resistance to interference from external RF sources.
13. IEC 61000-4-4 (Burst): Level 3
    • Specifies the ability of devices to withstand electrical fast transients. Level 3 indicates that the device is highly resistant to burst disturbances.
14. IEC 61000-4-5 (Surge): Level 3
    • Defines immunity to high-voltage surges. Level 3 ensures that devices can endure the most severe surge conditions without operational failure.
15. IEC 61000-4-8 (PFMF)
    • Tests immunity to power frequency magnetic fields. It ensures that devices are resilient to low-frequency magnetic fields often found in industrial and power environments.

Content created by Mike Day