A short post prompted by a (summarised) request from a customer:
We’d like to test to the following standards for our CE/UKCA marking
– EN 61326-1 (Class B emissions, Industrial immunity)
– EN 61000-6-2 (Industrial Level Immunity)
– EN 61000-6-3 (Class B Emissions)
This customer is very compliance conscious, as their products end up in all kinds of harsh and hazardous environments where they are protecting the health and safety (and lives in many cases) of their customers.
As such, it is understandable that they want to “throw the kitchen sink” at the EMC performance. Selecting Class B emissions and industrial immunity is a great way of demonstrating the robustness of your product in a wide range of electromagnetic environments.
So, why not quote all of the standards on the Declaration of Conformity (DoC)?
Guidance is Available
Thankfully the European Commission has published guidance on selecting Harmonised EMC and Radio standards for assessing the product to.
In each of these standards, a primacy or order of application, is given to the Harmonised Standards.
126.96.36.199 Relevant harmonised standards
The selection of the relevant harmonised standards is the responsibility of the manufacturer.
When the manufacturer chooses to apply harmonised standards he shall select them in the following precedence order:
– Product-specific standards (if available)
– Product family standards (if available)
– Generic standards
Product-specific (family) standards are those written by ESO’s taking into account the environment, operating and loading conditions of the equipment and are considered the best to demonstrate to compliance to the Directive.
An example of a product specific standard would be EN 61326-2-6 “Electrical equipment for measurement, control and laboratory use – EMC requirements – Part 2-6: Particular requirements – In vitro diagnostic (IVD) medical equipment (IEC 61326-2-6:2012)”
These product specific standards often refer back to the root family standard, EN 61326-1 in this case.
Only if the manufacturer’s equipment does not fall into a product standard should the generic standards be applied.
5.2 Generic harmonised standards vs product specific harmonised standard
A manufacturer which has the intention to apply a harmonised standard for the conformity assessment of its products, has to apply in priority the product specific harmonised standard and only if this one is not available, the generic one, in order to benefit of presumption of conformity with the essential requirements of the RED.
Applying Multiple Standards
There are cases where applying several different Harmonised Standards could be the correct thing to do.
For example, if the equipment is a piece of measurement equipment that incorporates a lot of IT functionality (networking, data storage, PC control) then the manufacturer could decide to assess against EN 61326-1 for laboratory equipment and against EN 55032 for IT equipment. Both standards would appear in the test report and on the DoC.
Presumption of Conformity
Remember that using Harmonised Standards (or Designated Standards for UKCA) gives you a “Presumption of Conformity” without further requirement to demonstrate compliance with the relevant directives/laws.
As this interesting piece on kan.de notes:
“Ultimately, the presumption of conformity is no more than a reversal of the burden of proof. This means that a product complying with the relevant [harmonised] standards may be challenged, for example by the market surveillance authority, only if actual evidence can be produced that the manufacturer has violated the requirements of the directives.”
Annex ZZ of a Harmonised Standard is your friend when it comes to understanding this link between the standards and the directives.
When the DoC Doesn’t Quite Cover It
This example of EN 61326-1 illustrates one of the problems of applying a Harmonised Standard that has multiple levels within it.
In this case, the EMC performance of equipment complying with EN 61326-1 could fall into one of six distinct categories.
- Class A (industrial)
- Class B (domestic)
- Controlled (shielded and filtered environment)
- Basic (domestic/commercial)
- Industrial (heavy machinery)
On the face of it, a product tested to Class A / Controlled (poor EMC performance) can’t be distinguished from one that has passsed Class B/Industrial limits (excellent EMC performance).
What to do?
The way I suggest overcoming this and informing the end user a little more clearly about the performance of the product is to explicitly state in the DoC what levels the product was assessed against during any testing.
This equipment was assessed against the following Harmonised Standards:
– EN 61326-1:2013 “Electrical equipment for measurement, control and laboratory use – EMC requirements – Part 1: General requirements” (Class B emissions, Industrial Immunity)
I hope you enjoyed this short dive into standards land. It’s a nice place to visit but you wouldn’t want to live there!