Joe, Your observations and conclusions are correct. EN (or IEC) 60950 is not really harmonized in this particular case.
According to the responsible authority for electrical safety in Sweden (Elsakerhetsverket), this case falls under the "special national conditions". I discussed this exact matter with them earlier this year. The supplier has to ensure that all products placed on the Swedish market complies with the safety regulations and Elsakerhetsverket's recommendation to overcome this particular problem (i.e. in the case of a modem with basic insulation between TNV-3 and SELV) was to put appropriate statements in the User's Guide to inform the user that the product cannot be used in Sweden (and Norway) despite the CE mark. I suggest that you contact Elsakerhetsverket yourself to get confirmation from the source: send e-mail to Mr Stefan Villa at [email protected]. Best Regards, Roger Magnuson ---------- Från: [email protected] Till: [email protected] Kopia: [email protected] Angående: CE marking vs. Annex ZB in EN60950 Datum: onsdag, augusti 19, 1998 18:57 <<Bifogad fil: ENVELOPE.TXT>> I am trying to sort out an an apparent contradiction between the main body of the "harmonized" EN 60950 and the national deviations that appear in Annex ZB. I would appreciate some assistance from the safety professionals and regulatory experts in the emc-pstc and treg forums. My particular problem has to do with the specified insulation between between TNV-3 circuits and SELV circuits, although the question about Annex ZB applies to other national deviations as well. I will use the TNV/SELV issue as an example. Clause 6.2.1.2 of EN 60950 specifies basic insulation between TNV-3 and SELV circuits. However, in Annex ZB, it states that Norway and Sweden require supplementary insulation. Annex ZB states that "for the countries in which the special national conditions apply, these provisions are normative. For other countries they are informative." I am trying to understand how this distinction is applied for CE marking. I thought that the intent of CE marking was that products could be evaluated against "harmonized" standards and then have the CE marking applied. I thought that products with the CE marking were allowed to move freely among the member countries in the EU. Annex ZB seems to complicate this simple interpretation. My tentative conclusions about the above situation are: 1) A manufacturer who intends to market his product in a list of EU countries that excludes Norway and Sweden can apply the CE marking to a product that has only basic insulation between TNV-3 and SELV circuits. 2) A manufacturer who intends to market his product in a list of EU countries that includes Norway or Sweden can only apply the CE mark if the product provides supplementary insulation between TNV-3 and SELV circuits. The above two cases result in products that each bear identical CE marking, but one of them (case 1) is technically illegal for use in Norway and Sweden. >From looking at the product marking, there is no way to determine that the product in case 1 should not be used in Norway or Sweden. I suppose that this distinction could be made in the user manual. I also presume that the manufacturer in case 1 would be obligated to ensure that the product is not offered for sale in Norway or Sweden. Maybe this is enough to comply with the letter of the law, but I suspect that it would be easy for the product in case 1 to find its way into Norway and Sweden. Prior to the adoption of CTR 21 for analog modems, the above issue was largely academic, since individual national approvals and the corresponding national labels were still required for connection to the PSTN. However, now that CTR 21 has been adopted, I expect there will be a rush toward "full" CE marking (including the crossed hockey sticks) of analog modems. National approval labels will no longer be required. I think this will bring additional attention to the situation I have described above. Can anyone offer some some insight into how this situation should be handled? Is my interpretation correct? Any comments would be welcome. Joe Randolph Telecom Design Consultant Randolph Telecom, Inc. 325 Highland Avenue Winchester, MA, USA 01890 781-721-2848 (voice) 781-721-0582 (fax) ***************************************************** ROGER MAGNUSON TGC AB, Sweden Tel: +46 8 56250042 Fax: +46 8 7050045 Internet Address: [email protected] *****************************************************
