What Is Harmonic Emissions — IEC 61000-3-2?
The harmonic emissions test is one in which the components of the device's drawn current at multiples of the mains frequency are measured and compared against limit values. It is aimed at protecting mains voltage quality.
Purpose of Harmonic Emissions — IEC 61000-3-2
The purpose is to verify that the device does not distort the mains current waveform beyond acceptable limits.
Which Products Is Harmonic Emissions — IEC 61000-3-2 Applied To?
- Switch-mode power supplies
- LED drivers and lighting
- Motor drives and inverters
- White goods
- Information-technology equipment
In Which Sectors Is Harmonic Emissions — IEC 61000-3-2 Used?
Standards Related to Harmonic Emissions — IEC 61000-3-2
- IEC 61000-3-2harmonic current emission test
Harmonic Emissions — IEC 61000-3-2 Conditions
- Harmonik mertebesi
- In IEC 61000-3-2, the 2nd to 40th harmonic is evaluated
- Equipment class
- Class A, B, C (illumination) or D (special waveform); limits vary by class
- Supply quality
- Voltage distortion of the test source is limited in the standard
- Measurement duration
- Time to cover the working cycle
Equipment for Harmonic Emissions — IEC 61000-3-2
- Harmonics and flicker analyser
- Low-distortion programmable AC power source
- Current and voltage measurement probes
- Data logging system
Sample Requirements for Harmonic Emissions — IEC 61000-3-2
- The sample must be operated at rated power and in the worst-case operating mode
- The equipment class must be correctly determined
- The operating cycle must be defined
- Rated input power must be documented
Duration of Harmonic Emissions — IEC 61000-3-2
Depends on the operating cycle; typically several hours.
Harmonic Emissions — IEC 61000-3-2 Procedure
- 1The equipment class and applicable limits are determined.
- 2The sample is powered from the low-distortion source.
- 3It is operated in the worst-case mode.
- 4Harmonic current components are measured over the defined duration.
- 5Results are compared with the class limits.
Harmonic Emissions — IEC 61000-3-2 Acceptance Criteria
The acceptance criterion is the harmonic current limits given per equipment class in IEC 61000-3-2. Devices below a certain power level are exempt in some cases.
Evaluation of Results
Each harmonic order is assessed separately. Tolerance rules permitted by the standard apply to short-duration exceedances.
Harmonic Emissions — IEC 61000-3-2 Report
- Applied standard and equipment class
- Rated input power and operating mode
- Source voltage distortion
- Harmonic current values and limit comparison
Accreditation
EUROLAB holds internationally recognised accreditation obtained from accreditation bodies party to the IAF and ILAC multilateral recognition arrangements, under ISO/IEC 17025 for laboratory testing, ISO/IEC 17020 for inspection and surveillance, and ISO/IEC 17021-1 and ISO/IEC 17065 for system and product certification. This chain ensures the reports and certificates issued are accepted worldwide.
Whether this test can be offered within accredited scope depends on your product and the standard applied; since accreditation is method-based, the scope is confirmed in writing at the quotation stage.
Scope and authorisationsRelated Regulations
- EMC 2014/30/EU
- EcoDesign requirements (for relevant products)
EMC / EMI Testleri — What Does This Testing Field Cover?
The section below describes the field that the Harmonic Emissions test belongs to; the conditions and acceptance criteria of this particular test are given in the sections above. The scope specific to your product is confirmed in writing at the quotation stage.
EMC testing answers a question with two sides: does the device emit an unacceptable level of electromagnetic interference into its surroundings (emission), and does it withstand the interference coming from them (immunity)? The two sides are measured with separate tests and separate set-ups, and both are required.
The field exists because of a simple physical fact: every conductor carrying current behaves like an antenna. A switched-mode power supply, a motor drive or the clock signal of a microcontroller radiates radio frequency energy even though it was never designed to. The same conductor also works in reverse: an external field induces a voltage across it. In an environment crowded with devices, this mutual effect means devices disturbing one another.
On the emission side, conducted and radiated emission are measured separately. Conducted emission is the interference the device imposes on its mains and communication cables and dominates at lower frequencies. Radiated emission is the field the device releases into the air and comes to the fore at higher frequencies. The two are measured in different set-ups, and the limits vary by product group.
On the immunity side, real-world sources of interference are simulated: electrostatic discharge (human touch), radiated radio frequency fields (a nearby transmitter), electrical fast transients (switching), surges (lightning and mains events), conducted radio frequency, power-frequency magnetic fields, voltage dips and short interruptions.
The standard to be applied depends on WHERE the product is used, and that choice determines the entire outcome. Residential and industrial environments carry different sets of limits; in vehicles the UNECE R10 regime applies rather than CE; for medical devices IEC 60601-1-2 brings additional requirements; and for products containing a radio, radio legislation comes into play and harmonised ETSI standards are used.
In immunity testing the acceptance criterion is a PERFORMANCE CRITERION class, not a binary pass/fail. A device continuing to function without interruption during the test, being temporarily affected and recovering by itself, or recovering only through user intervention are different classes. Which class is acceptable is defined in the product standard; the tolerance for a device carrying a safety function differs from that of a consumer device.
The most common shortcoming of an EMC file is that it covers only one side. A file carrying an emission report alone is not complete in terms of the EMC directive. The second common gap is a test set-up that does not represent actual use: if the device is measured on a bare bench with cables different from its real ones, the result does not carry over to the field.
Method groups in this field
Conducted emission
Interference imposed on the cable through mains and communication ports, measured via an artificial mains network (LISN).
Radiated emission
The field released into the air by the device, measured at a defined distance in an anechoic or semi-anechoic chamber.
Harmonics and flicker
The harmonic content of the current drawn from the mains and voltage fluctuation; the side that affects mains quality.
Electrostatic discharge
Contact and air discharge together with indirect discharge; the most frequently applied immunity test.
Radiated and conducted RF immunity
The device is exposed to a defined field strength and to an RF signal injected into the cable.
Mains-borne events
Electrical fast transients, surges, voltage dips and short interruptions.
Commonly confused in this field
- An emission report alone does not complete an EMC file; immunity must be demonstrated as well.
- An FCC report is not accepted in a CE file; the limits, measurement distances and set-ups are different.
- The EMC Directive does not apply to vehicles; the UNECE R10 regime does. Specifications requiring both together should be reviewed.
- The warning that a Class A device may cause interference in a residential environment is mandatory in the manual; market surveillance checks that this warning is present.
- The test set-up is part of the report. If cable type, length or routing changes, the result changes; measurement must be made in the series-production configuration.
- CISPR 22 and CISPR 13 have been withdrawn; their current counterparts are CISPR 32 and CISPR 35.
Which decisions these results support
- CE declaration under the EMC Directive
- The EMC part of radio equipment conformity
- A UNECE R10 file for a vehicle component
- Resolving field interference complaints and correcting the design
- Assessing the EMC impact of a board or wiring-harness change
Related Tests
Frequently Asked Questions About Harmonic Emissions — IEC 61000-3-2
According to which standard is Harmonic Emissions made?
Harmonic Emissions is executed in scope IEC 61000-3-2, IEC 61000-3-12 and EN 61000-3-2. The limit values and acceptance criteria to be applied are defined in the product standard; The version valid for your product is confirmed in writing at the offer stage.
Which products does Harmonic Emissions apply to?
Mainly applied to Switch-mode power supplies, LED drivers and lighting, Motor drives and inverters, White goods and Information-technology equipment. Whether your product is included in the scope is determined by examining its technical specifications and intended use.
Under what conditions is Harmonic Emissions done?
The determining parameters are: Harmonik mertebesi — In IEC 61000-3-2, the 2nd to 40th harmonic is evaluated, Equipment class — Class A, B, C (illumination) or D (special waveform); limits vary by class and Supply quality — Voltage distortion of the test source is limited in the standard. The full terms are in the "Test Conditions" section on the page and vary depending on the product standard.
What kind of sample is needed for Harmonic Emissions?
The sample must be operated at rated power and in the worst-case operating mode, The equipment class must be correctly determined and The operating cycle must be defined. The number of samples is determined according to the product standard and the scope to be reported.
How long does Harmonic Emissions take?
Depends on the operating cycle; typically several hours. This duration belongs to the experiment itself; sample preparation, queuing and reporting are also evaluated. A realistic schedule for your product is given in the offer.
What is the Harmonic Emissions result called "appropriate"?
The acceptance criterion is the harmonic current limits given per equipment class in IEC 61000-3-2. Devices below a certain power level are exempt in some cases.