What Is Ring Wave?
Ring wave test is an immunity test in which damped oscillatory voltage waves resulting from network switching are applied to device lines. It is defined in IEC 61000-4-12.
Purpose of Ring Wave
The goal is to verify that the device continues to function during oscillatory transients that occur in events such as capacitor bank switching.
Which Products Is Ring Wave Applied To?
- Mains connected electronic devices
- industrial control equipment
- Building and facility automation
- Power electronics products
In Which Sectors Is Ring Wave Used?
Standards Related to Ring Wave
- IEC 61000-4-12
- IEC 61000-6-2
Ring Wave Conditions
- waveform
- Damped wave with 100 kHz oscillation frequency
- Seviye
- Defined in the standard; typical values 0.5 – 4 kV
- Application points
- Line–line and line–ground
- Phase angle and repetition
- Pulses at defined phase angles and numbers
Equipment for Ring Wave
- ring wave generator
- Coupling–decoupling network
- Reference ground plane
- Function-monitoring system
Sample Requirements for Ring Wave
- The sample must be set up in its typical use configuration
- The presence of protection elements must be documented
- The function-monitoring method must be defined
- Function must be checked before the test
Duration of Ring Wave
It depends on the number of points and polarity; typically half business day.
Ring Wave Procedure
- 1The test setup and coupling network are established.
- 2The level and points to be applied are determined.
- 3A defined number of pulses are applied at each point, polarity and phase angle.
- 4The function is monitored.
- 5Permanent damage is checked.
Ring Wave Acceptance Criteria
The resulting performance criterion is evaluated as A, B or C. Permanent damage is not accepted.
Evaluation of Results
The energy of the oscillating wave is lower than the surge experiment, but the frequency content may reveal different sensitivities. Therefore, it does not replace surge.
Ring Wave Report
- Applied standard and level
- Waveform and application points
- Phase angles and pulse numbers
- Function observations and performance criteria
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
EMC / EMI Testleri — What Does This Testing Field Cover?
The section below describes the field that the Ring Wave 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 Ring Wave
According to which standard is Ring Wave made?
Ring Wave is executed in scope IEC 61000-4-12 and IEC 61000-6-2. 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 Ring Wave apply to?
Mainly applied to Mains connected electronic devices, industrial control equipment, Building and facility automation and Power electronics products. Whether your product is included in the scope is determined by examining its technical specifications and intended use.
Under what conditions is Ring Wave done?
The determining parameters are: waveform — Damped wave with 100 kHz oscillation frequency, Seviye — Defined in the standard; typical values 0.5 – 4 kV and Application points — Line–line and line–ground. 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 Ring Wave?
The sample must be set up in its typical use configuration, The presence of protection elements must be documented and The function-monitoring method must be defined. The number of samples is determined according to the product standard and the scope to be reported.
How long does Ring Wave take?
It depends on the number of points and polarity; typically half business day. 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 Ring Wave result called "appropriate"?
The resulting performance criterion is evaluated as A, B or C. Permanent damage is not accepted.







