Re: Notified Bodies and Test Samples
Richard Woods wrote A Notified Body for EMC has told us that we must keep the test sample for 10 years. Since there is nothing in the Directive that requires samples to be kept, we find this request to be unacceptable. We have a TCF and understand that it must be kept for 10 years after production ceases. Has anyone else encountered this type of requirement by a Notified Body? I agree with you Richard, I haven't read anywhere that you legally must keep your sample for 10 years. I suppose though if at some point if things have gone badly and someone questioned your results, it might help your in your defense of due diligence if you could produce the item tested and could show that it didn't differ from your production. Really though, for most of us to keep a sample or samples as the case may be, of everything we ever tested would call for some pretty big warehouses. Perhaps you should get them to quote you exactly what document and clause that they have extracted this requirement from, maybe then will have a reply more to your liking. Regards, Kevin Harris Manager, Compliance Engineering Digital Security Controls Canada 416 665-8460 Ext 378
Re[2]: Notifed Bodies and Test Samples
In 1982 the TUV Rheinland representative in New York told me the same thing. I complained and explained that I wanted to see this in writing. He never did produce anything to back this up, but tried to persuade me verbally that this was a reasonable requirement. I disagreed. I could see warehouses upon warehouses of golden units awaiting their capital destruction at the end of ten years, in the meantime costing millions of occupied space. I don't consider this reasonable. When the TUV Rheinland office opened here on the west coast, they did not insist on this requirement and I did not bring it up for fear of opening a Pandora's box. In today's environment of ISO certification, technical files, and complete test reports, I find this requirement ludicrous. If I were faced with this request I would fight it and/or switch bodies. Tania Grant, Octel Communications Corporation tania.gr...@octel.com __ Reply Separator _ Subject: Re: Notifed Bodies and Test Samples Author: eric.lif...@natinst.com (Eric Lifsey) at P_Internet_Mail List-Post: emc-pstc@listserv.ieee.org Date:2/3/97 12:37 PM I've never heard of such a requirement though I keep test samples for my own reasons and/or sanity, and I don't keep them all. However, I've noticed this sort of problem with CBs before. CBs are not as unified in their methods and interpretations as you might hope they'd be. This is primary reason why I avoid using CBs except for the (very) rare consultation; the last time was over a year ago, and the two CBs had opposing opinions on the matter. I've never had to deal with a NB, so far. Eric Lifsey National Instruments ___ Subject: Notifed Bodies and Test Samples From:WOODS; RICHARD wo...@sensormatic.com at Internet List-Post: emc-pstc@listserv.ieee.org Date:2/3/97 8:25 AM A Notified Body for EMC has told us that we must keep the test sample for 10 years. Since there is nothing in the Directive that requires samples to be kept, we find this request to be unacceptable. We have a TCF and understand that it must be kept for 10 years after production ceases. Has anyone else encountered this type of requirement by a Notified Body?Received: from natinst.com by hail.natinst.com with SMTP (IMA Internet Exchange 2.0 Enterprise) id 2F628990; Mon, 3 Feb 97 12:04:09 -0600 Received: from ruebert.ieee.org (ruebert.ieee.org [199.172.136.3]) by natinst.com (8.8.4/8.8.4) with ESMTP id MAA23131; Mon, 3 Feb 1997 12:04:04 -0600 (CST) Received: (from daemon@localhost) by ruebert.ieee.org (8.7.5/8.7.3) id IAA05476 for emc-pstc-list; Mon, 3 Feb 1997 08:37:49 -0500 (EST) Message-ID: c=US%a=_%p=Sensormatic%l=SENSORMATI/SFLAEXCHAN/0001b...@flgwyex1.sensormatic.co m From: WOODS, RICHARD wo...@sensormatic.com To: Safety e-saf...@dorado.crpht.lu, EMC emc-p...@ieee.org Subject: Notifed Bodies and Test Samples List-Post: emc-pstc@listserv.ieee.org Date: Mon, 3 Feb 1997 08:25:00 -0500 X-Mailer: Microsoft Exchange Server Internet Mail Connector Version 4.0.837.3 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-emc-p...@majordomo.ieee.org Precedence: bulk Reply-To: WOODS, RICHARD wo...@sensormatic.com X-Resent-To: Multiple Recipients emc-p...@majordomo.ieee.org X-Listname: emc-pstc X-List-Description: Product Safety Tech. Committee, EMC Society X-Info: Help requests to emc-pstc-requ...@majordomo.ieee.org X-Info: [Un]Subscribe requests to majord...@majordomo.ieee.org X-Moderator-Address: emc-pstc-appro...@majordomo.ieee.org
PWB Layout for high frequency traces...
Hello all, I am looking for a method to determine the minimum distance which I can route 1 GHz traces from other devices (including metal pin row headers) without compromising the EMC performance (characteristic impedance) of the traces, while preventing any common-mode coupling to the other devices. Any formulas, suggestions, or ideas are appreciated. Also, if anyone knows of any EMC layout modelling software which addresses this issue, please let me know. Thank you, Randall T. Flinders Emulex Corporation r_flind...@emulex.com
OSHA-29 CFR 1910 Subpart S
There seems to be some different interpretations as to the scope of OSHA-29 CFR 1910 Subpart S. This subpart DOES NOT apply to all equipment that plugs into the AC mains. The Introduction specifically states 1910.301 (a) Design and safety standards for electrical systems These regulations are contained in 1910.302 through 1910.330. Sections 1910.302 through 1910.308 contain safety standards for electrical utilization systems. Included in this category are all electrical equipment and installations used to provide electric power and light for employee workplaces. Sections 1910.309 through 1910.330 are reserved for possible future safety standards for other electrical systems. Later in 1910.399 utilization systems are define as (128) A utilization system is a system which provides electric power and light for employee workplaces,and includes the premises wiring system and utilization equipment. utilization equipment is described just above this in 1910.399 (127) Utilization equipment means equipment which utilizes electric energy for mechanical, chemical, heating, lighting or similar useful purpose. This definition clearly does not cover a computer unless maybe it is used to control one of the elements above. The introduction specifically reserving 1910.309 through 1910.330 for other electrical systems indicates that there are other types of systems that do not fall under these standards. This specification is design to handle installations in the workplace, NOT the design of individual pieces equipment. The only electrical systems that need to be approved which is acceptible equipment as designated in 1910.399 (1) are those covered by this subpart which was described in the introduction and then redefined in 1910.399 (128). Engineers at our company have been told at seminars that UL or approved equipment was necessary to plug into the mains due to this CFR. This misinformation has led to alot of confusion and misdirected effort. Clearly there are state and local regulations that vary. I am not sure about the source of these regulations other than those specified in the NEC. It is definitely easier if the inspectors see a mark from an NRTL; however, I am not sure that it is actually required by the state and local regulations. This has only been a concern when our equipment was put into a new building that was under construction. It has seldom been an issue when the equipment (small rack mount equipment) was installed after the facility was built. Maybe the inspectors and the facilities engineers also have a different interpretation of the regulations. Jim Stafford HPS Product Engineer. (These comments do not necessarily reflect the views of my employer).
Re: Laser measuring equipme
Or, try Melles-Griot. Their general catalog also lots of basic optics information you may find useful. They have a sales office in Boulder, CO: 4665 Nautilus Court South Boulder, CO 80301 fax: 303-581-0960 Regards, Peter L. Tarver Nortel peter_tarver-mt...@nt.com -- Try GNNettest. I know they make equipment to measure lasers used in fiber optic networks. 315-797-4449. Jon D. Curtis, PE Hello all, Does anyone know where and who sells laser measuring equipment. Specifically to measure the actual output of the lasers to meet the requirements set forth by IEC 825-1 and the FDA's 21 CFR 1040.10. Thanks in advance. Richard Georgerian Product Compliance Eng. Exabyte e-mail: richa...@exabyte.com tele: 303-417-7537 fax: 303-417-7829
Korea product safety
Does anyone know the product safety and emc requirements for Korea? Do we know of any directives?
Re: PWB Layout for high frequency traces...
r_flind...@emulex.com wrote: Hello all, I am looking for a method to determine the minimum distance which I can route 1 GHz traces from other devices (including metal pin row headers) without compromising the EMC performance (characteristic impedance) of the traces, while preventing any common-mode coupling to the other devices. Is this an analog or digital signal? A rule of thumb that I've *seen* used is no closer than 1/4 inch. Parasitic end effects that are difficult to model come into play. This was used in an ECL based 10GHz digital design. Formal *characteristic impedence* of the traces will not be comprised theoretically since it is based on a ratio of inductance/inch and capacitance/inch parameters of the trace. Ideally, trace length should not make a difference of characteristic impedence as crazy as that sounds. Common-mode coupling will be a challange. I hope your not using FR-4 for board material? The comments and opinions stated herein are mine alone, and do not reflect those of my employer.
RE: PWB Layout for high frequency traces...
Hi, You may want to do a little research from the website www.emclab.umr.edu University of Missouri-Rolla is heavily involved in EM numerical modeling techniques. Regards, tony_fredriks...@netpower.com -- From: r_flinders To: emc-pstc; EMFLDS-L Subject: PWB Layout for high frequency traces... List-Post: emc-pstc@listserv.ieee.org Date: Monday, February 03, 1997 4:06PM Hello all, I am looking for a method to determine the minimum distance which I can route 1 GHz traces from other devices (including metal pin row headers) without compromising the EMC performance (characteristic impedance) of the traces, while preventing any common-mode coupling to the other devices. Any formulas, suggestions, or ideas are appreciated. Also, if anyone knows of any EMC layout modelling software which addresses this issue, please let me know. Thank you, Randall T. Flinders Emulex Corporation r_flind...@emulex.com
Re: PWB Layout for high frequency traces...
Randall; The routing of 1GHz traces has many obstacles. Following are a few (not an exhaustive list) 1) dielectric constant value variance 2) cross talk 3) source termination 4) source impedance 4) end-line termination 5) common mode generation 6) component inability to handle 1GHz signals 7) mismatched impedances 8) vias 9) turns and corners of traces 10) PCB material 11) connectors and headers, etc. etc. One advice is to keep the trace on one plane only. No vias, and use rounded turns. For additional signal integrity (less emissions is a benefactor of good S.I.) you will have to use differential transmission lines, i.e. two traces for each signal. Those have to be kept precisely at the same distance apart and driven from differential drivers. The impedance of the transmission line is not so important as long it is held constant. (Unless you are driving external devices) Remember that it is difficult to get high impedances (over 50 Ohm) on a typical multilayer PCB. There are signal integrity programs that do just what you want but they are not cheap! visit the University of Missouri at Rolla web-site (something like UMR.emclab.edu or close to that) You will find a treasure of information there. Hans Mellberg EMC Consultant __ Reply Separator _ Subject: PWB Layout for high frequency traces... Author: Non-HP-owner-emc-pstc (owner-emc-p...@majordomo.ieee.org) at hp-boise,uugw2 List-Post: emc-pstc@listserv.ieee.org Date:02/03/97 03:06 PM Hello all, I am looking for a method to determine the minimum distance which I can route 1 GHz traces from other devices (including metal pin row headers) without compromising the EMC performance (characteristic impedance) of the traces, while preventing any common-mode coupling to the other devices. Any formulas, suggestions, or ideas are appreciated. Also, if anyone knows of any EMC layout modelling software which addresses this issue, please let me know. Thank you, Randall T. Flinders Emulex Corporation r_flind...@emulex.com
Re: Transformer Approvals
EN60704 is the CENELEC version of IEC 704. IEC 704 is titled Test Code for the determination of airborne acoustical noise emitted by household and similar electrical appliances I suspect that the are making an unresonable request! Hans Mellberg EMC Consultant __ Reply Separator _ Subject: Transformer Approvals Author: Non-HP-owner-emc-pstc (owner-emc-p...@majordomo.ieee.org) at HP-Boise,mimegw2 List-Post: emc-pstc@listserv.ieee.org Date:02/03/97 12:46 PM At the end of last year, we shipped a piece of laboratory equipment to France that required CE approval. We evaluated it for approval as laboratory equipment in terms of complying with EN 61010-1. It was evaluated for EMC compliance. In this piece of equipment, I used (2) transformers that posses EN 60950 certification. The company that purchased the equipment, retained another company to evaluate CE compliance. They have indicated that these transformers are unacceptable as they do not posses certification to either EN 60704 or EN 607542. I don't have a copy of either of these standards available at the moment, although we are looking into purchasing a copy. Can someone give me some idea as to why a transformer meeting these requirements is believed by this company to be necessary or if there is something that I can do to make the existing transformers acceptable for use? Thanks for any assistance that you can provide.. John Bielot
