Hi Jim and all else who is confused by this 60950 issue-- You are not alone! As a document service, we get this question all the time and depending on what national body you talk to, you may get different answers from them. This is the official story from IEC and BSI:
If you purchased BS EN 60950 (published by BSI), the cover states "incorporates amendments 1, 2, and 3, and IMPLEMENTS amendment 4, not published separately". This "implements" idea tends to confuse people. But it simply means that BSI stipulates that the user should use IEC 60950 amendment 4 as the official amendment (it says this, in not so many words, in the text). This BS EN edition does state some brief changes that are made in the amendment 4, but it's basically summarizing the changes given in IEC amendment 4. The fact that BS EN 60950 amendment 4 is "not published separately" is correct - there is not a BSI-published amendment 4. There is only the notice in the complete document that the user should use IEC amendment 4. To confuse you more, there is actually a straight EN 60950 amendment 4 (direct from CEN). I have several copies and they too state that the user should use IEC 60950 amendment 4. So to get back to the original issue, there is NOT a complete 60950 document that incorporates amendment 4. The reason being that BS EN is not going to incorporate an IEC amendment into its publication, and IEC simply does not have an incorporated version just yet. If you were to purchase the BSI edition, it would come with amends. 1, 2, 3 and a note about amend. 4 telling you to use the IEC amend. 4, but not the actual amend. 4. If you were to purchase the IEC edition, you would receive a 60950 incorporating amends. 1, 2 and 3, and if the agent you purchase from has any knowledge of the subject, they should ask you if you also need amendment 4, sold separately (notice this is the actual, real-life, down-and-dirty, elusive amendment 4 that everyone needs). Don't make the mistake of just obtaining the document 60950, because most sellers will not send you the amendment 4 unless you ask for it. IEC amendment 4 IS available as a stand alone. It's nearly 150 pages and it comes with very clear explanation of what pages to replace. Hopefully, you have the original document in a looseleaf, and you can take 15 minutes to replace the pages. If you need more information, or need to obtain a copy, feel free to touch back. Happy New Year, May all the standards developers in the world get together, and never make anything this confusing again! -- Andrew Bank Custom Standards Services, Inc. http://www.cssinfo.com Engineering Documents and Information Services (800) 699-9277 (734) 930-9277 FAX (734) 930-9088 Ask me about --IEC Standards on CD-ROM --PERINORM - The new International Standards Database --The new 1998 ASME Boiler and Pressure Vessel Code (http://www.cssinfo.com/bpv1998.html) These are all available now at great discounts! Jim Eichner wrote: > Season's Greetings: > > I have just reviewed the two "versions" (IEC vs. EN) of "A4" to 950 that > we received > recently, and I'm confused. > > As outlined in the attached e-mail below, A4 is extensive, and modifies > most of the pages in the standard. What we really need is a complete, > stand-alone EN60950 incorporating all amendments up to and including the > IEC's A4 stuff. I am now in doubt whether this exists! > > Here's what we ordered and received: > > We ordered IEC950 A4 and received an inch-thick set of replacement pages > that need to be inserted into an existing copy of IEC950 (1991). What > we thought we were getting was a stand-alone completely updated IEC > standard. Oh well. > > We also ordered EN60950/A4, formally titled "Safety of information > technology equipment (IEC950:1991/A4:1996, modified)". This document is > only 15 pages long, contains only a few revisions (primarily some > "common modifications" and new/revised annexes ZA, ZB, ZC, and ZD), and > is meant to be used with EN60950:1992 and its previous amendments A1, > A2, and A3. Its content in no way resembles the list of changes below. > > Am I incorrect in expecting the EN's A4 to implement the > IEC's A4, or is the EN's A4 unrelated, and > the EN version of the IEC's A4 is still to come? > > Can someone please explain what's going on here, and point us > to a source for a complete, stand-alone EN60950 incorporating the IEC's > A4 > amendment? > > Thanks, > > Jim Eichner > Statpower Technologies Corporation > [email protected] > The opinions expressed are those of my invisible friend who really > exists (honest)! > > Original Message----- > From: robertj@anetMHS (Robert Johnson){MHS:[email protected]} > Sent: Saturday, June 21, 1997 10:29 PM > To: mvaldman@anetMHS{MHS:[email protected]}; JEichner; > bceresne > Cc: emc-pstc@anetMHS{MHS:[email protected]} > Subject: EN60950 amendment 4 content > > [email protected] wrote: > >... as we know, IEC950 amendment 4 is out for some > >time. Can someone please send a note of the changes > >(DELTA) it contains relative to the previous version? > > Fourth amendment changes include > Voltage measurement > Component compliance criteria > Restricted access locations > Operator and service access > Introduction of TNV-1, -2 and -3 circuits > Extensive changes to TNV circuit criteria and testing > Integration of SELV and TNV requirements > Titling of all clauses > Enhancement of compliance statements > Changes to clearance and insulation requirements > New labeling requirements > Insulated winding wire criteria > Improved criteria for operational insulation and fault testing > Error correction and editing > Many other changes to clarify interpretations, correct wording > or cover new constructions. > > The amendment is extensive and complex. Over half the pages have been > modified. So the message is, don't try to guess its impact from a list > like the above. The amendment is available from IEC and from national > agencies like ANSI. Get a copy and do an evaluation that meets your own > needs. The modifications are margin marked. No brief description would > be compelete enough to cover your needs and I can't quote the entire > amendment. You need to consider the actual wording in relation to your > product to assess its impact.
