IEC EN 60255-22-7 Electrical Relays - Part 22-7: Electrical Disturbance Tests for Measuring Relays and Protective Equipment - Power Frequency Immunity Tests

The standard “IEC EN 60255-22-7 Electrical relays - Part 22-7: Electrical disturbance tests for measuring relays and protection equipment - Power frequency immunity tests”, which has its origin in a European standard and was subsequently published by the International Electrotechnical Commission (IEC), is based on the concepts described in the standard “IEC 61000-4-16 Electromagnetic compatibility (EMC) - Part 4-16: Testing and measurement techniques - Immunity test for conducted common mode disturbances in the frequency range 0 Hz to 150 kHz”. This standard, where applicable, references this standard and describes the general requirements for power frequency immunity tests for measuring relays and protection equipment for power system protection (including control, monitoring and process interface equipment used with these systems).

The purpose of the tests is to confirm that the equipment under test will operate properly when energized and subjected to short-duration conducted, common- and differential-mode power frequency disturbances applied to direct current (DC) inputs at the rated frequency of the equipment under test, e.g., 162/3 Hz, 50 Hz, and 60 Hz. Testing of pilot wire schemes between substations is not covered by this standard.

The requirements specified in this standard apply to measuring relays and protection equipment in a new condition and all tests specified are type tests only.

The main purpose of this standard is to specify:

• Definitions of terms used
• Test severity levels
• Test equipment
• Test setup
• Test procedures
• Accept conditions
• test report

In general, power frequency magnetic field immunity testing is designed to evaluate the ability of electronic devices to withstand magnetic field disturbances at power frequencies, typically 50 Hz or 60 Hz. These disturbances can originate from power lines, transformers or other electrical devices and can cause malfunctions, degraded performance or even catastrophic failure. Power Frequency magnetic field immunity testing ensures that electronic devices can withstand these disturbances without degrading their performance, thus increasing their reliability and safety.

Power frequency magnetic field immunity testing standards vary by region and product category. Some of the most common standards include:

• The standard “IEC 61000-4-8 Electromagnetic compatibility (EMC) - Part 4-8: Testing and measurement techniques - Power frequency magnetic field immunity test” defines test methods and requirements for electronic devices to withstand power frequency magnetic field disturbances.
• The standard “EN 61000-4-8 Electromagnetic compatibility (EMC) - Part 4-8: Testing and measurement techniques - Power frequency magnetic field immunity test” is a European adaptation of the IEC 61000-4-8 standard and contains the same test methods and requirements.
• The “Federal Communications Commission (FCC) Part 15 Radio frequency devices” standard establishes the regulatory framework for EMC testing in the United States, covering electronic devices that emit radio frequency energy.

Power frequency magnetic field immunity testing can be applied in a variety of industries, including consumer electronics, automotive, aerospace, telecommunications, medical devices, and industrial equipment. By complying with magnetic field immunity testing standards, manufacturers can ensure that their products are resistant to magnetic field disturbances and can operate and coexist reliably in relevant environments.

Power frequency immunity test failures can be caused by a variety of factors, including:

• Inadequate shielding: Inadequate shielding of components, cables, or enclosures can make electronic devices more susceptible to power frequency magnetic field disturbances.
• Poor component selection: Components that are more sensitive to magnetic field disturbances can cause failures in the Power frequency magnetic field immunity test.
• Design flaws: Design issues such as inadequate grounding, poor layout, or inadequate insulation between sensitive components can lead to reduced immunity to power frequency magnetic field disturbances.

The following techniques are generally applied to resolve power frequency magnetic field immunity test failures:

• Improve shielding: To reduce the sensitivity of the device to power frequency magnetic field disturbances, it is necessary to improve the shielding of components, cables, and enclosures.
• Selecting robust components: Components with higher immunity to magnetic field disturbances should be selected to improve overall system performance.
• Optimizing device design: Design improvements such as better grounding, optimized layout, and increased isolation between sensitive components are implemented to increase the device's immunity to power frequency magnetic field disturbances.

Our organization has a strong staff that closely follows the developments in the world in the field of science and technology and constantly improves itself. Among the numerous test, measurement, analysis and evaluation studies provided for businesses in various sectors, there are also test services in accordance with the standard “IEC EN 60255-22-7 Electrical relays - Part 22-7: Electrical disturbance tests for measuring relays and protection equipment - Power frequency immunity tests”.