Re: Survey: Experiences with EMI Consultants
Max, It sounds as though you don't have any expertise in-house, so I would recommend getting a consultant into the design phase - as early as possible. Alot will depend upon the product though. The higher the frequency - the tougher the problems, pcb routing is critical. Do you have to meet Class A or Class B? Is the enclosure metal, is it already designed, I would suggest that the consultant work directly with the design engineers during schematic review, a mechanical review, and largely during pcb layout. The more you do then, the less you have do worry about later, you may find that you don't even need the consultant through the testing and certification phase. But if you wait UNTIL then, you may wind up losing alot of sleep. You don't say where you're located, so I can't recommend anyone specific, but in my experience - yes - there are excellent consultants available - worldwide (but also, buyer beware). I hope this helps some. Best regards, Stephen C. Phillips Telecom Engineer === Direct: 508-244-8116 Fax: 508-244-8039 | |Cisco Systems, Inc. ||| ||| Core Business Unit | | 250 Apollo Drive | |Chelmsford, MA 01824 | U.S.A. E-mail: step...@cisco.com === All opinions expressed are my own, not necessarily those of Cisco Systems. - Begin Included Message - >From owner-emc-p...@mail.ieee.org Fri Jul 12 16:52:15 1996 To: emc-p...@ieee.org Subject: Survey: Experiences with EMI Consultants From: Max I am wondering if anyone has had experience with hiring EMI/EMC consultants to solve their problems and what sort of results they have obtained. I would be very interested in any details that anyone might be able to provide. For example, did you use a consultant after the system was prototyped or early on, during the design process. Was the consultant most useful at providing board-level, design suggestions or was he most helpful at providing after-the-fact type fixes that pertain to cabinet design and I/O cable filtering and grounding techniques, etc. Also, did the consultant, deal directly with design engineers or interface with just one person within your company, etc.? Does anyone have the names of any good consultants? Max Kelson mkel...@es.com - End Included Message -
RE: creepage and clearance in IEC1010-1
Clause D1, Annex D, IEC1010-1 This clause does imply that you can reduce C&C (ignore the entire annex) provided certain conditions are met; -Circuit is not mains -All single fault tests in 4.4 do not result in hazard -No hazard accessible after fault Without this clause being present the whole of annex D would be mandatory whenever invoked by the standard. I can't see any other way to interpret it. It may not help you very much though. If you reduce your C&Cs to the point where they only meet the requirements of Basic Insulation then clause 4.4.2.11 may demand that this Insulation be short-circuited. (Failure of basic insulation is a Single Fault). Individual cases differ but obviously be very careful if you are relying on fault testing to get you through. I would rather keep my C&Cs within Annex D if function permits it. Regards, Trevor Haworth. Product Approvals Manager Design to Distribution Ltd t.hawo...@kid0109.wins.icl.co.uk
Re: Voltage for 3 pahse systems
Hi Moshe. You wrote: > Would anyone know what are the voltages/frequencies used in the > various countries/environments around the world for high power > industrial 3 phase equipment? > As others have suggested, a very good document id the British Standards book/wallchart "World Electricity Supplies". supplied by their export support group 'THE' (Technical Help for Exporters). Apart from the voltages and frequencies, this book gives invaluable information on the TYPE of supply. e.g. : Star. centre Neutral, centre Earth. (5 wire) Star, centre Neutral/Earth (4 wire) Delta, one point earthed, centre tapped one leg earth, Open Delta, centre tapped one side, end earthed. ...and just about every possible combination of three phases, neutral and earth mathmatically possible! Most are used somewhere on this mortal coil of ours. Chris Dupres EMC Specialist. VG Microtech. cdup...@vacgen.fisons.co.uk tel +44 (0) 1825 761077 fax +44 (0) 1825 768343 'Opinions expressed are personal, not necessarily Corporate'
Analog phone for ISDN BRI in Australia
Phones, (either analogue or digial) that interface via the ISDN (BRI or PRI) have the ability to make calls to PSTN telephones. Rightly or wrongly, Austel require all ISDN products with telephones (digital or POTS via ISDN) to comply with Austel TS004 for voice frequency performance, along with safety to TS001, EMI & TS013 or TS014 of course. We can test to TS013 BRI part B (layer 1), which calls up TS004. Martin Garwood aust...@mpx.com.au Courtesy of RCIC http://uc.com/compliance_engineering/
Re: Analog phone for ISDN BRI in Australia
Item Subject: Analog phone for ISDN BRI in Australia Received: from relay.hp.com by hpausa1.aus.hp.com with ESMTP (1.37.109.16/15.5+ECS 3.4 Openmail) id AA025600275; Tue, 16 Jul 1996 22:31:18 +1000 Received: from ruebert.ieee.org by relay.hp.com with ESMTP (1.37.109.16/15.5+ECS 3.3) id AA259060271; Tue, 16 Jul 1996 05:31:11 -0700 Received: (from daemon@localhost) by ruebert.ieee.org (8.7.5/8.7.3) id GAA19286 for emc-pstc-list; Tue, 16 Jul 1996 06:07:42 -0400 (EDT) From: pman...@shiva.com Message-Id: <199607161001.gaa09...@apollo.gti.net> List-Post: emc-pstc@listserv.ieee.org Date: 16 Jul 96 05:59:23 To: t...@sdd.hp.com Cc: emc-p...@ieee.org Subject: Analog phone for ISDN BRI in Australia X-Mailer: Allaire Cold Fusion 1.5 Sender: owner-emc-p...@majordomo.ieee.org Precedence: bulk Reply-To: pman...@shiva.com X-Resent-To: Multiple Recipients 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 ... Item Subject: Analog phone for ISDN BRI in Australia Greetings Pierre-Marie, I had such a product approved a couple of years ago with another company. What is tested depends heavily on the test lab being used but in most cases its valid. They are concerned with such things as gain, distortion, tone generation (eg. busy tone and dial tone) and DTMF recognition. They may also test the PSTN line voltage and ring wave for voltage and safety. Austel are concerned with protecting the network, the users and maintaining a level of performance. If you have a specific issue you wish to discuss, I suggest you talk to Dr Vembanor Marney on +61 3 9828 7328. He the senior test report reviewer for Austel. I hope this helps Regards David -- David Mitchell Regulatory Specialist Hewlett-Packard Australian Telecom Operation 347 Burwood Highway, Burwood East, Victoria, Australia 3151. Internet: david_c_mitch...@aus.hp.com HPdesk: DAVID C. MITCHELL / HP-Australia, om2 Phone: +61 3 9210 5610, Telnet 2105610, Fax: +61 3 92105570 -- __ Reply Separator _ Subject: Analog phone for ISDN BRI in Australia Author: Non-HP-owner-emc-pstc (owner-emc-p...@majordomo.ieee.org) at HP-Australia,shargw1 List-Post: emc-pstc@listserv.ieee.org Date:16/7/96 5:59 AM On our ISDN BRI product there is an analog input phone to be used on the ISDN.We have been requested to test this feature based on TS003,related to PSTN.However there is NO external connection to PSTN rather to ISDN network. This analog input should be covered by the TS013 (ISDN BRI). Has somebody experienced the same problem ? thanks for your answer Pierre-Marie ANDRE pan...@shiva.com Shiva International Pierre-Marie Andre pman...@shiva.com Courtesy of RCIC http://uc.com/compliance_engineering/
Re: crrepage and clearance in IEC1010-1
John, Look at Clause 3.8 of ANSI/ISA S82.01-1994 (US harmonized version of IEC 1010-1) for a definition of "mains". Clause D.1 means that if your circuit (input or measuring) DOES NOT connect to the mains, then you may test according to the single fault conditions of Clause 4.4. For example; if your instrument takes a measurement of the voltage at a wall socket of 120 V then you must meet the CREEPAGE AND CLEARANCE requirements . Dan Teninty P.E. Senior Product Safety Engineer teni...@tc.fluke.com FLUKE Corporation Everett, Washington (206) 356-6035 (206) 356-6490 fax I=92ve never been able to fully determine the intent and meaning of clause D.1 of IEC1010-1, which states: Suppose I have a double insulation system which relies on both supplementary insulation and basic values of creepage and clearance (C&C) to keep the operator safe from hazardous live (non-mains) conductors. Couldn=92t I invoke D.1 to permit me to make my C&Cs as small as I want, thereby effectively reducing my entire insulation system to that of basic levels? =20 Am I completely missing the meaning of D.1, and if so, can anybody explain the intent and ramifications of this clause? =20 Regards, John Quinlan quinl...@voicenet.com =20
Re: Voltage for 3 pahse syst
Hi, The World Electric Guide website URL is http://www.cris.com/~kropla/electric.htm Enjoy. tony_fredriks...@netpower.com -- From: Kazimier Gawrzyjal To: Moshe Valdman Cc: emc-pstc Subject: Re: Voltage for 3 pahse syst List-Post: emc-pstc@listserv.ieee.org Date: Tuesday, July 16, 1996 12:54PM RE>Voltage for 3 pahse systems 7/16/96 Kaz-ESN 765-4805 Moshe, I believe there exists a document, put out by the U.S. Department of = Commerce (National Technical Information Service), titled " Electric = Current Abroad 1991 Edition". By the title, this document is likely out = of date but still highly useful.. It outlines power systems throughout = the world as well as the type of attachment plugs used in principal = cities throughout the world. There may also be a website available. Regards, Kaz Gawrzyjal Safety Engineer Nortel 0307...@nt.com -- List-Post: emc-pstc@listserv.ieee.org Date: 7/16/96 10:35 AM To: Kazimier Gawrzyjal From: Moshe Valdman - E X T E R N A L L Y O R I G I N A T E D M E S S A G E - Hello everyone, Sorry, I asked this several days ago and got no response, so maybe = the email just didn't come through. Would anyone know what are the voltages/frequencies used in the various countries/environments around the world for high power industrial 3 phase equipment? thanks moshe valdman -- RFC822 Header Follows -- Received: by nmisq2.miss.nt.com with SMTP;16 Jul 1996 10:33:31 -0400 Received: from ruebert.ieee.org by corpgate.rich.nt.com with SMTP (PP); Tue, 16 Jul 1996 14:31:26 + Received: (from daemon@localhost) by ruebert.ieee.org (8.7.5/8.7.3) id = JAA23446 for emc-pstc-list; Tue, 16 Jul 1996 09:44:15 -0400 (EDT) List-Post: emc-pstc@listserv.ieee.org Date: Tue, 16 Jul 96 16:34:16 EST From: Moshe Valdman Message-Id: <9606168375.aa837560...@mail.stil.scitex.com> To: emc-p...@ieee.org Subject: Voltage for 3 pahse systems Sender: owner-emc-p...@majordomo.ieee.org Precedence: bulk Reply-To: Moshe Valdman X-Resent-To: Multiple Recipients 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
RE: EN60950 Transition Periods for ITE
Hello All, My question involves license upgrades for EN60950. I have an ITE product that was tested and approved to 60950 1988. TUV notified me in April, 1996 that, as of Jan 1st 1996, my product license was no longer valid and that I would have to update to EN60950 A2 1993 (minimum). The gating factor here turns out to be the third party power supply which meets EN60950 A2, 1991. There would be an additional cost (payable to TUV of course) involved to upgrade the power supply license not to mention any redesign. I'd rather not go through this if it's not necessary. I have a chart which explains the transition periods for EN60950. This chart comes from TUV. The way I am reading it, it tells me that for products certified before March 1 1995, EN60950 A2 1991 is good until 3/1/2000. Is my interpretation correct?? or is EN 60950 A2 1993 the minimum acceptable version for existing ITE products? As always, all related view points are appreciated. Thanks, George Sparacino 508-691-4635
Re: TTE Directive as it applies to VSATs
You should have come to the seminar we gave last week in Toronto and San Jose as it was stimulated by the proposed new CTE (Connected Telecommunications Equipment) Directive. The proposal is still being worked and if there is a draft text, it is not out yet. However, one of the facets of the new proposal is to do away with all "a-priori" testing and rely on "a-posteriori" surveillance, for all telecom terminal equipment. It is going to be a couple of years before you see it. By that time, if you get a-posteriori" surveilled, you'd better have your act together because any equipment that fails to meet the essential requirements of the new Directive (NOT ETSI Standards) will be found "defective" and subject to the full force of the Product Liability Directive with fines up to 70 M ecus. Ciao, Vic