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The Automotive EMC directive Summary The Automotive EMC Directive is a CE marking Directive that requires manufacturers to gain type approval for all vehicles and electronic sub assemblies, components and separate technical units to be used in vehicles. Certain types of equipment are exempt from certain tests. Equipment for caravans and motor homes that operate when the vehicle is in use are included in the Directive, but those that only operate when the vehicle is parked or are powered independently are excluded. Products that have direct control of the vehicles must not emit EMC emissions above the specified limits and must be immune to the interference levels stated in the Directive. However, products without direct control only have to meet the emission requirements. The Directive contains 3 groups of tests and states their acceptance levels. They are; narrow band emissions, broad band emissions and immunity tests. The Directive came into force in October 2002, and is enforced by a different body in each member state. In the UK this is the Vehicle Certification Agency (VCA) which is part of the Department of Transport. The VCA practices worst case selection prior to testing, to reduce the amount of testing required. Testing must be conducted by an authorised lab or be witnessed by the VCA e.g. if the manufacturer has their own test facility. VCA assessors will also examine the quality control systems in place in the factory. Approved products should have an e mark (instead of the CE mark) followed by the distinguishing number or letters of the Member State which has granted type approval. Contents Purpose The Automotive Electromagnetic Compatibility Directive 95/54/EC (AEMCD) is one of the Article 100a directives which are intended to promote free trade throughout the European Union and the wider EEA. Prior to enactment of the AEMCD, electrical equipment intended for use in motor vehicles was covered by the EMC Directive 89/336/EEC. However, the application of Directive 89/336/EEC to vehicles is complicated by a number of other pre-existing directives and so an anomalous situation where components and STUs were CE marked but the complete vehicle was not was common. More significantly, Directive 89/336/EEC is not primarily concerned with safety. The automotive industry was concerned that neither the standards nor the attestation procedures under the 89/336/EEC were adequate to ensure safe operation in vehicles where compatibility with (for instance) engine management and braking systems are critical for the safety of passengers. On the basis of these concerns, the industry successfully lobbied the Commission to introduce new measures which removed components and sub-systems for road vehicle applications from the scope of 89/336/EEC and introduce a new single market regime which allows for different standards and a stricter attestation procedure. 95/54/EC establishes that regime, and is shortly to be replaced with directive 2004/104/EC which clarifies certain issues and strengthens the regime still further. The directive requires manufacturers to gain type approval for all vehicles, electronic sub assemblies (ESA’s), components and separate technical units (STUs). This means that any device, or a part of the vehicle (whether it is an original part or an after market part) needs to be approved before it can be sold. This includes equipment that is designed to get its power from the cigarette lighter socket as well as equipment for permanent installation. Definitions of vehicles, ESAs, components and STUs are as follows: Definition of a Vehicle from 70/156/EEC: "Vehicle" means any motor vehicle intended for use on the road, with or without bodywork, having at least four wheels and a maximum design speed exceeding 25 km/h, and its trailers, with the exception of vehicles which run on rails and of agricultural tractors and machinery." Definition of Component or Separate Technical units from 92/53/EEC: "Component" means a device, such as a lamp, subject to the requirements of a separate Directive, intended to be part of a vehicle, which may be type-approved independently of a vehicle where the separate Directive makes express provisions for so doing." "Separate technical unit (STU)" means a device, such as a rear protective device, subject to the requirements of a separate Directive, intended to be part of a vehicle, which may be type-approved separately but only in relation to one or more specified types of vehicle, where the separate Directive makes express provisions for so doing." Definition of Electronic sub assembly (ESA) from 95/54/EC: "Electrical/electronic sub-assembly" (ESA) means an electrical and/or electronic device or set(s) of devices intended to be part of a vehicle, together with any associated electrical connections and wiring, which performs one or more specialized functions. An ESA may be approved at the request of a manufacturer as either a component or a separate technical unit." In essence the requirements of the Directive are very simple - it basically states that products that have direct control of the vehicle must not emit electromagnetic emissions above the limits and that products must be immune to the interference levels stated in the directive. For products that have no effect on the direct control of the vehicle are require only to meet the emissions requirements. The Directive came fully into force on 31 October 2002 and all equipment which comes within its scope must now comply with its provisions. In the UK, the enforcing authority is the Vehicle Certification Agency (VCA) which is an agency of the Department for Transport. Each EU member state has their own body responsible for enforcing the Directive but the general structure of testing and approval is the same and so only the UK situation is considered in detail here. The EMC tests in 95/54/EC are separated into three groups;
Definitions of the levels above which emissions are defined as unwanted or below which pollution and noise are accepted are specified in the directive. (An academic point, but one worthy of note nonetheless, is that this approach is different from that of Directive 89/336/EEC where the requirements are contained in standards rather than the directive itself). There are exemptions from some of the tests for certain types of equipment: 1. If the equipment does not have a electronic oscillator with an operating frequency greater than 9 kHz, it is considered to comply with the narrow band emission requirements without further testing. 2. Vehicles which do not have electrical or electronic systems or ESAs involved in the direct control of the vehicle do not require immunity testing. 3. ESAs which are not involved in the direct control of the vehicle do not need immunity testing. The definition of "Drivers direct control" comes from Annex I, section 6.4.2.3: " The driver's direct control of the vehicle is exercised by means of, for example, steering, braking, or engine speed control." Application The manufacturer should apply to the VCA for the work to be done. If an independent test house is to be used then contact with the test house should be made direct, but a letter to the VCA should still be sent, stating which test house is to be used. (Test houses designated as ‘Technical Services’ can handle this aspect of the approval on behalf of clients so as to provide a ‘one stop shop’ service.) Worst case selection The VCA practices worst case selection prior to testing in order to reduce the amount of testing needed across the range of a product types. A meeting should be held between the VCA (or the Technical Service who will act as a proxy for the VCA) and the manufacturer in order to consider the products to be tested, the tests to be carried out, and the date and venue for the testing. Testing The VCA does not have its own EMC test facilities and is not a designated "competent body" under the EMC Directive. Instead, they have accredited many laboratories both in the UK and abroad. A full list can be found in the VCA Publication VCA054 Test Facilities Suitable for Automotive EMC tests to 95/54/EC. Organisations that are authorised as Technical Services can handle the whole process for the manufacturer. They will give the manufacturer a price for the complete test including the VCA fees for the issue of the approval certificate. Tests carried out at laboratories that are not Technical Services must be witnessed by the VCA. If the manufacturer wants the VCA to act as the Technical Service, they can witness the test work being carried out at any of the laboratories listed. The manufacturer takes out a job number with the VCA and will be responsible for making the test booking with the test laboratory, paying the test laboratory and paying VCA for witnessing the test and issuing the approval certificate. These arrangements allow the manufacturer to choose the test house that they want to use and then to arrange with them for relevant reports and information documents to be sent to the VCA. The VCA then issue the approval certificate and document package. If a manufacturer has their own EMC test facilities then the VCA can witness tests on site, without the involvement of any other test house. This will require a formal appraisal of the manufacturer’s test facility by the VCA. Type approval requires the testing of a sample and inspection of the documentation for the technical specification. It also requires conformity of production - confirmation that the manufacturer can consistently produce products to the approved specification. To do this the VCA quality assessors will examine the quality systems in place in the factory. The approach follows established quality system principles as in ISO 9002. Certification to ISO 9002 will normally be accepted in place of factory assessments, though control plans dealing with issues specific to type approval activities may be needed in addition. Marking requirement, the "e mark" The AEMCD has a different approval mark from the CE mark directives. Instead of the CE logo, products approved to the AEMCD should carry the ‘e’ mark. This mark consists of a rectangle surrounding the letter 'e' followed by the distinguishing number or letters of the Member State which has granted type-approval. The marking must also include, in the vicinity of the rectangle, the four-digit sequential number, referred to as 'base approval number', preceded by two figures indicating the sequence number assigned to the most recent major technical amendment to Directive 72/245/EEC on the date EEC component type-approval was granted. (The test house or Technical Service will advise the manufacturer of this number during the approval process.) If an electrical or electronic system has been approved as part of a whole vehicle test then that system does not require "e" marking. The same system sold as a spare part will also not require "e" marking. It is, however, recommended that the packaging bears the "e" mark. Non original-fit equipment e.g. aftermarket products, and ‘pattern’ replacement parts, will need to be "e" marked. ESAs and STUs will also require "e" marking. This includes in-car entertainment systems, cigarette lighter socket connected electrical devices (including mobile phone chargers) and after-market alarm systems. The EEC type-approval mark must be affixed to the main part of the equipment in such a way as to be clearly legible and indelible. Machinery Directive and the Automotive EMC Directive The Machinery Directive 89/392/EEC sets out essential health and safety requirements for "machinery". Products covered by the machinery Directive must meet the requirements of the relevant Directives and be ‘CE’ marked. The generic EMC Directive 89/336/EEC generally applies to products covered by the Machinery Directive. However, machinery intended to be fitted to a road vehicle can be considered to be a vehicle component, therefore if the vehicle falls within the scope of 95/54/EC, the machinery fitted to that vehicle may also fall within the scope and consequently be governed by the AEMCD. In certain cases, e.g. non-road mobile machines such as construction or agricultural machines, the whole vehicle will have been designed as a piece of mobile machinery. Such vehicles fall outside 95/54/EC and hence will have to comply with the EMC directive (89/336/EEC). Equipment in caravans and motor homes Equipment that is intended for vehicles and operates when the vehicle is in use should comply with the automotive directive (95/54/EC). Equipment which is powered independently from the vehicle supply and which can only be used when the vehicle is parked should comply with 89/336/EEC. The bad news for manufacturers of products within the scope of the AEMCD is that they need to have every piece of apparatus approved by the VCA and this means testing. On the other hand, if the product can work independently from the vehicle then it may also come under the EMC directive (89/336/EC). Often it will be possible to combine the testing and save some of the cost. Most manufacturers of automotive electrical products have little to fear from the Directive and type approval should be straightforward so long as they take a logical approach to the requirements and maintain accurate records. Many consultants and test houses are offering services to help manufacturers to meet their obligations so companies which do have problems have no shortage of people to whom to turn for help. However, it is important to be sure that you actually have a problem before spending time and money trying to solve it. Remember that consultants and test houses have a vested interest in getting you to spend money on their services, so a little time spent doing some basic familiarisation research for yourself may well be a good investment. As with all directives, the actual requirements for any piece of equipment under the directive and harmonised standards are complex and dependent on not only the design but also the type of user, the intended use and sometimes even what is claimed in the instructions or sales literature. Conformance are not an EMC test laboratory, nor do we specialise in EMC related design. We do, however, know several people who are specialists and we're happy to recommend reputable test laboratories to clients where testing is actually necessary. We also have extensive experience of applying the requirements of the Directive and CE marking equipment as part of a package where (as is usually the case) the Automotive EMC Directive is only one of several directives which have to be considered. For further advice specific to your products, please contact us at Conformance and we will be pleased to discuss your needs. If you'd like us to prepare a no-obligation quote for assisting you with E marking your products, please take a look at our required information page in order to be able to give you an accurate idea of the costs and procedures involved. The Vehicle Certification Agency are the UK Government agency which enforces the Directive. Their website includes several useful documents including a list of test houses and Technical Services. Radio Frequency Investigation (RFi) are a testing and consultancy organisation specialising in electromagnetic compatibility, among other issues. They offer many services relating to consultancy and approval solutions to the existing and revised edition of 2004/104/EC, details of which can be found on their web site.
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