For some electrical or electronic apparatus or systems, harmonised standards do not exist, or cannot be applied because equipment is physically large. In some cases, a relevant standard may exist but it is not harmonised—its reference number has not been published in the OJEU.
In these and other instances, the route to demonstrating conformance to the EMC Directive is by using a Technical Construction File.
The European EMC Directive states in Article 4:
The apparatus [...] shall be so constructed that:
- the electromagnetic disturbance it generates does not exceed a level allowing radio and telecommunications equipment and other apparatus to operate as intended;
- the apparatus has an adequate level of intrinsic immunity to electromagnetic disturbance to enable it to operate as intended.
The EMC Directive also defines, under Article 10, the routes for demonstrating conformity with these protection requirements.
The principal route, via Article 10 (1), is to demonstrate that the apparatus meets the requirements of harmonised European standards (eg the product specific standard BS EN 55022 covering emissions from ITE; or the generic standards in the EN61000-6-X series).
Where standards do not exist for equipment or they can only be applied in part, then Article 10 (2), the Technical Construction File (TCF) route, must be used.
A TCF is the documentation which demonstrates that a product (or product family) meets the protection requirements of the EMC Directive. The TCF must include a report or certificate from a Competent Body asserting the information contained in the TCF is consistent with conformity to the Directive. As with the standards route to conformity, the manufacturer is ultimately responsible for the Declaration of Conformity to the Directive.
Essentially a manufacturer has to show that the product in question is designed to meet the EMC requirements of the operating environment. This will be accomplished by showing that appropriate measures have been taken in the design, which are verified by test data and/or a theoretical assessment. For larger projects, supporting evidence will include EMC management, control and test plans.
A Competent Body is an independent third party which satisfies certain requirements including technical competence, professionalism of personnel and possession of civil liability insurance. In the UK, Competent Bodies are appointed by the DTI.
York EMC Services Ltd is a DTI-appointed European Competent Body for the preparation and assessment of Technical Construction Files.
A TCF is used:
The DTI provides some recommendations (159 kB PDF) as to the structure of a TCF. It should contain three sections:
These are now described in more detail:
Parts I and II of the TCF can be written by the manufacturer in cooperation or consultation with the Competent Body. When applying for a report or certificate, the manufacturer must make a statement of single submission (ie there is no outstanding application to another Competent Body). The Competent Body will prepare the Competent Body report and certificate. The manufacturer is responsible for the declaration of conformity of products certified via the TCF route. The role of the Competent Body is to assert that the evidence contained within the TCF is consistent with conformity. It is the manufacturer’s responsibility to ensure that the information is correct and that subsequent production units are consistent with it.
York EMC Services Ltd has built a reputation as a leading supplier of EMC services in the UK. We can provide testing, consultancy and Competent Body services to companies operating in a wide range of industry sectors. We recently archived our 200th Competent Body Assessment, making us one of the most active Competent Bodies in the UK. Specifically we can offer:
Our independence and impartiality guarantee that you can trust York EMC Services Ltd to perform all projects with competence and integrity. Contact us for more information.
Last updated 2007-Mar-28.
