EMC

ElectroMagnetic Compatibility (EMC) is a characteristic of electrical and electronic equipment that permits it to operate as intended in the presence of other electrical and electronic equipment, and not to adversely interfere with that other equipment. All such equipment emits electrical energy, and some of that emitted energy may interact and interfere with other equipment. Equally, equipment may be susceptible to receiving energy emitted from other sources. Obviously, radio transmitters and receivers are intended to emit and receive electrical energy, but other equipment may not be intended to do so.

Even transmitters and receivers may emit and receive unwanted energy that may prevent those devices, or others, from functioning as intended. It is part of the EMC 'art' to design and operate equipment so that it is both prevented from emitting spurious energy that can cause interference and is immune to the adverse effects of any spurious energy that it may receive.

EMC regulation

As the effects of interference have severe consequences, EMC is frequently a subject of national and international regulation. Within Europe, EMC regulation is managed mainly through the European Commission's EMC Directive (2014/30/EU) and for Radio equipment through Directive 2014/53/EU. However, there are many types of equipment that are excluded from the EMC Directive, although EMC requirements for most of them are included in other Directives and regulations. Here are some examples:

  • Equipment covered by the Radio Equipment Directive (RED)
  • Certain aeronautical items
  • Automotive components
  • Medical devices, including implantable devices
  • Marine equipment
  • Amateur radio equipment not available commercially.

The EMC Directive and many of the other relevant Directives are 'New Approach' Directives. As such, they rely for their operation on Harmonised Standards developed by recognized European standards bodies, such as ETSI. Harmonised Standards define technical characteristics which can be used to demonstrate compliance with the essential requirements of the Directive.

In the case of the EMC Directive, the essential requirements are that equipment shall be designed and manufactured such that:

  • the electromagnetic disturbance it generates does not exceed a level allowing radio and telecommunications equipment and other apparatus to operate as intended; and
  • the apparatus has an adequate level of intrinsic immunity to electromagnetic disturbance to enable it to operate as intended.

Equipment which meets Harmonised Standards is presumed to comply with the essential requirements, and a manufacturer may declare conformity with the Directive. Alternatively, manufacturers may choose to request certification of equipment by a recognized third party, known as a 'Notified Body'.

Electrical equipment (including telecommunications equipment) intended to be fitted to a motor vehicle are considered to be 'Electronic Sub Assemblies (ESA)' and are required to meet Automotive EMC requirements. These requirements are set out in Directive 2004/104/EC, a specific Directive which forms part of European legislation for automotive type approval. The annexes of this Directive contain all the technical requirements necessary to demonstrate conformance which allows the ESA to be placed on the market.

The Directive covers two categories of after market equipment ESAs:

a) After market equipment intended for installation in a motor vehicle, and which are not related to immunity related functions of the motor vehicle. As a general rule these are ESAs which are not related to an immunity-related function of the motor vehicle, are connected directly to the vehicle's dc supply, and are not involved/related with any of the vehicle functions (described in Annex 1, clause 2.1.12 of the Directive).

b) After market equipment intended for installation in a motor vehicle, and which is related to immunity related functions of the motor vehicle, as set out in Annex 1, clause 2.1.12 of the Directive, is subject to full type approval requirements of the Directive.

The Automotive EMC Directive recognizes conformity according to the procedures of the EMC Directive and the Radio Equipment Directive (RED). This includes the CE marking for after market ESAs described in category a) above, but additionally requires that the limits of the clauses referenced in Annex 1, clause 3.2.9 of the Automotive EMC Directive are fulfilled.

ETSI has accepted the standardization request for Harmonised Standards under the revised EMC Directive and communicated its initial work programme, consisting of Harmonised Standards addressing radio equipment and telecommunications network equipment, to the Commission.

Most EMC standards covering radio equipment are addressed under the Radio Equipment Directive.

A summary of ETSI’s work programme related to the EMC Directive (and the RED) can be xlsmdownloaded from this website

You can check EMC directive Harmonised Standards referenced in the Official Journal.

Other EMC Harmonised Standards are developed by Cenelec. Close co-operation is maintained with CENELEC to ensure consistency and avoid gaps or overlaps in the work programmes.

ETSI has a cooperation agreement with CENELEC for the production of EMC standards, under which:

  • EMC for Telecommunications Terminal Equipment is standardized by CENELEC
  • EMC for Telecommunications Network Equipment is standardized by ETSI
  • EMC for Radio Equipment and Systems (including radio telecommunication terminal equipment) is standardized by ETSI.

EMC standards for telecommunications network equipment

ETSI has the following EMC standards for Telecommunications Network Equipment:

  • EN 300 386, a Harmonised Standard for telecommunications network equipment
  • ES 201 468, a standard providing additional requirements for enhanced availability of service.

EMC standards for radiocommunications equipment

ETSI has created a multi-part EMC standard (EN 301 489) for EMC for radio equipment, in accordance with the Radio Equipment Directive.

Part 1 of EN 301 489 covers EMC requirements that are common to all radio equipment. The subsequent parts specify additional requirements that are specific to a particular radio service. These include mobile and aeronautical communications, TV broadcasting, satellite services, medical devices and radars.

Marine radio is treated separately. Equipment subject to carriage requirements under the International Maritime Organization (IMO) convention for Safety of Life at Sea (SOLAS) are covered by the Marine Equipment Directive, and the related ETSI standards for this purpose contain EMC, radio and environmental requirements in one document.

Other marine equipment is subject to the Radio Equipment Directive. The EMC requirements are included in EN 301 843, which follows a similar structure to EN 301 489 for land-based equipment.

EMC standards for automotive equipment

The EN 301 489 series of standards specifies relevant EMC requirements for radio communications equipment, and several parts of this series have been updated to take account of the additional technical requirements of the Automotive EMC Directive. Of particular note:

  • EN 301 489-1 (general EMC requirements for radio equipment)
  • EN 301 489-7 (specific EMC requirements for GSM terminals)
  • EN 301 489-24 (specific EMC requirements for IMT-2000 CDMA Direct Spread (UTRA) terminals)

International activities

ETSI is an international member of CISPR, the International Special Committee on Radio Interference. This Steering Committee makes the strategic and policy decisions for CISPR. ETSI members are very active in CISPR sub-committee I which writes the global EMC standards for Information Technology equipment and telecom terminal equipment. CISPR I determines the radio-frequency emission limits for all telecommunications equipment which are then incorporated into the ETSI EMC product standards. ETSI also participates in the International Electrotechnical Commission (IEC) Advisory Committee on Electromagnetic Compatibility (ACEC), which co-ordinates EMC standardization in IEC.

A full list of related standards in the public domain is accessible via the ETSI standards search. Via this interface you can also subscribe for alerts on updates of ETSI standards.