Re: Calibration of test equipment
As I understand it the interpretation to have tracibility to your national authority through equipment used only for calibration originated with NAMAS. Some other accreditors have picked it up since then. The requirement need not be that onerous. You can calibrate your own equipment traceably to your national authority using equipment that you send out for calibration. Where the instrument is cheap (multimeter) we buy an extra and use it only for calibration. Where it is expensive (oscope, receiver), we use it for calibration only directly after it returns from outside calibration (or inside tracible cal) and after we have calibrated our secondary equipment with it we put it into regular service for the year. If you manage your yearly calibration cycle well this shouldn't crimp your style too much. The key is not to have equipment in your calibration chain back to the national authority that has been used for non-calibration purposes between the time of its calibration and that of the secondary calibration. The idea is to have high confidence that the tracibilty chain is intact. If a piece of equipment in the chain has been used daily in regular rough and tumble testing it is seen as having a much higher probability of operating outside of its tolerances. In my experience the outside cal houses are pretty tough on their gear too, so I am not sure that much is gained. I personally think this interpretation is overly severe, but we comply with it because we want our test reports to be accepted by authorities who think this process is reasonable. To directly answer your specific question about a signal generator used in immunity: If it is being used as an uncalibrated signal source in the measurement and you are using a power meter or receiver for tracibility then you can use that signal generator, even if it went off a cliff the day before. If you are relying on the calibrated output level that the signal generator says it is putting out, then you should not have used that instrument in non-calibration use since its last calibration. Jon. Flinders, Randall wrote: Does this mean that a signal generator that is used for Radiated Immunity testing should not be used to calibrate Pre-Amps and Cables? How about Antenna Calibration? Can you use the same receiver you use on the OATS to calibrate those? I know this is a common practice with Commercial Test Labs. Is there guidance as to what types of equipment can be used for both lab use and for the calibration of other equipment? michael.sundst...@nokia.com wrote: I think there is a special requirement to keep the calibration equipment separate from the EMC equipment. In other words the calibration equipment can only be used for the calibration process and not for testing EMC. Michael Sundstrom Product Test Technician EMC Nokia Mobile Phones, Dallas PCC * Email michael.sundst...@nokia.com % Desk (972) 374-1462 *Mobile (817) 917-5021 * Fax (972) 374-0901 amateur call: KB5UKT --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.rcic.com/ click on Virtual Conference Hall, --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.rcic.com/ click on Virtual Conference Hall, -- Jon D. Curtis, P.E. Director of Engineering Curtis-Straus LLC One Stop Laboratory for NEBS, EMC, Product Safety, and Telecom Testing. 527 Great Road Littleton, MA 01460 USA Voice 978-486-8880 Fax 978-486-8828 email: jcur...@curtis-straus.com WWW.CURTIS-STRAUS.COM --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc
Re: FCC Part 15 Class B
See 15.101. Class B personal computers and peripherals may use either the Certification or Declaration of Conformity equipment authorization procedure. Other class B digital devices and peripherals are subject to the Verification equipment authorization procedure. Be careful as Verification is not the same as Declaration of Conformity with different labeling requirements, test site accreditation requirements, etc. See 47 CFR Part 2 for detailed descriptions of the equipment authorization procedures. Jon Curtis. Courtland Thomas wrote: Hello Group, I would like to know if it is permissible to self verify to Class B for ITE. I know it can be done for Class A, but I am not sure about Class B. The interesting thing is that I posed the question to a contact at the FCC and the answer I got was No idea. Courtland Thomas Patton Electronics --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org -- Jon D. Curtis, P.E. Director of Engineering Curtis-Straus LLC One Stop Laboratory for NEBS, EMC, Product Safety, and Telecom Testing. 527 Great Road Littleton, MA 01460 USA Voice 978-486-8880 Fax 978-486-8828 email: jcur...@curtis-straus.com WWW.CURTIS-STRAUS.COM --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Re: SAR Measurements
For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org -- Jon D. Curtis, P.E. Director of Engineering Curtis-Straus LLC One Stop Laboratory for NEBS, EMC, Product Safety, and Telecom Testing. 527 Great Road Littleton, MA 01460 USA Voice 978-486-8880 Fax 978-486-8828 email: jcur...@curtis-straus.com WWW.CURTIS-STRAUS.COM --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Re: Downloadable CE marks
We have it in bit map in the guest center at www.curtis-straus.com -Jon. Mike Stone wrote: Good Morning-Is anyone aware of a web site that has downloadable CE marks?Thanks in advance. Regards, Michael Stone L.S. Compliance W66 N220 Commerce Court Cedarburg, Wi 53012 V 262-375-4400 F 262-375-4248 -- Jon D. Curtis, P.E. Director of Engineering Curtis-Straus LLC One Stop Laboratory for NEBS, EMC, Product Safety, and Telecom Testing. 527 Great Road Littleton, MA 01460 USA Voice 978-486-8880 Fax 978-486-8828 email: jcur...@curtis-straus.com WWW.CURTIS-STRAUS.COM
Re: FCC certifications
Whoa! Part 68 requires trade names to be disclosed to the commission in a mod filing. I agree with your statement for Part 15. For Part 68 you can either have the new company file for a re-certification which requires a letter of permission from the original registrant or the original registrant can add the new company's name to their registration as a trade name by doing a modification filing. In a re-certification the new company gets a new FCC Registration Number. If they are added as a trade name, then the registration number stays the same. wo...@sensormatic.com wrote: You may label any FCC Certified product with any brand name and no change is required to the certifications. The FCC ID numbers of the product identify the holder of the grants and those numbers are not related to the brand name appearing on the product. Richard Woods -- From: k...@i-data.com [SMTP:k...@i-data.com] Sent: Friday, September 29, 2000 9:00 AM To: emc-p...@majordomo.ieee.org; t...@world.std.com Subject: FCC certifications Hi all, I can't find the answer to the following questions in the information I have from FCC I hope that sombody can help me. We have both FCC part 15 certified products and FCC part 68 certified products. Now a OEM costumer wants to have our product with his name on FCC certified. Both a product with part 15 only and one also including part 68. Are we allowed to use our FCC ID on his labels or do we need to apply for a new FCC ID ? (The OEM version is our product in a new color and without our name) If we need a new FCC ID what is the procedure for this ? Hopefuly we can transfere the approvals directly. Best regards, Kim Boll Jensen i-data Denmark --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org -- Jon D. Curtis, P.E. Director of Engineering Curtis-Straus LLC One Stop Laboratory for NEBS, EMC, Product Safety, and Telecom Testing. 527 Great Road Littleton, MA 01460 USA Voice 978-486-8880 Fax 978-486-8828 email: jcur...@curtis-straus.com WWW.CURTIS-STRAUS.COM --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Re: VCCI application
There is a pdf version of the form in the guest center on our web site at www.curtis-straus.com -Jon Curtis. Jim Bacher wrote: forwarding for : bgilmar...@cereva.com Reply Separator Subject:VCCI application Author: Gilmartin; Bob bgilmar...@cereva.com Date: 9/27/00 1:46 PM Hello group, Does anybody have an application for VCCI they can forward to me. I went to the VCCI website and it's a Catch-22-I can't download an application for membership until I have a membership (i.e. username and password). There is also no link to email VCCI. Bob Gilmartin Sr. Regulatory Engineer Cereva Networks, Inc. 3 Network Drive Marlboro, MA 01752-3083 (508) 486-9660 x3412 phone (508) 486-9776 fax --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org -- Jon D. Curtis, P.E. Director of Engineering Curtis-Straus LLC One Stop Laboratory for NEBS, EMC, Product Safety, and Telecom Testing. 527 Great Road Littleton, MA 01460 USA Voice 978-486-8880 Fax 978-486-8828 email: jcur...@curtis-straus.com WWW.CURTIS-STRAUS.COM --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Re: NEBS: GR-63 Altitude Test Profile
Hi, At the last two NEBS conferences Mike Bentley of USWest stated that all he was concerned about was the EUT performance at high temperature. What changes at altitude is the heat capacity of air. Thus it becomes more difficult to cool equipment because the air is thin. USWest is the RBOC which is most concerned with this test as they are the only one to my knowledge with COs above 12,000 feet. We run the altitude test at 50C for frames and 55C for shelves. We allow the EUT to stabilize within the chamber and we also determine the temperature at which equipment starts to fail in the event that the EUT has a problem at the extreme temperature. ATT NEDS does have a non-operational test at 40,000 feet which we run at ambient temperature and humidity as an unpressurized airplane bay is unlikely to be very hot.. BTW, the next NEBS conference is in Baltimore next week. See www.800teachme.com for details. -Jon Curtis David Spencer wrote: Hi Jeffrey, Our friends at Telcordia do seem to enjoy listing requirements where we would least expect them. GR63 is no exception. For altitude, the limits called out in R4-8 [74] and O4-10[76] for Table 4-4 are the general temperature/humidity limits for long and short term exposure. The application of those criteria can be found in Table 4.5 in the 182 hour profile. It is my belief that you test to at 4000m using the profile from table 4.5, unless you wanted to make a profile of your own that covered the same ground over a longer period of time, using Table 4-4 for the limits, rates of change, and duration. If the EUT cannot tolerate the resulting temperature rise from the 4000m altitude, it will be necessary to retest at 1800 to meet R4-8. The failure is documented in the NEBS data submitted to the carrier who decides if it is something he wants you to do something about before he purchases you equipment. I do not think it is necessary to test 1800m if you have passed the table 4-5 profile at 4000m. Don't forget: Objective requirements are not elective. The tests must be performed and the results documented. It is by this means that decisions are made about making the objective a mandatory requirement down the road. Good Luck! Dave Spencer Compliance Engineer Oresis Communications, Inc. 14670 NW Greenbrier Parkway, Beaverton, OR 97006 * dspen...@oresis.com * http://www.oresis.com * (503) 466-6289 * (503) 533-8233 -Original Message- From: Collins, Jeffrey [mailto:jcoll...@ciena.com] Sent: Monday, September 25, 2000 6:36 AM To: 'emc-p...@ieee.org ' Subject: NEBS: GR-63 Altitude Test Profile Group, GR-63 sections 4.1.35.1 do not give a definitive testing profile for Altitude testing. If you have completed this test what profile did you use? Is there a customer specification from an RBOC or CLEC that you found to be definitive. It appears that by only addressing these sections you could have to retest down the road for a customer located in a high altitude environment. Which Telco has the most stringent internal specifications for this test? Points to be considered are: * Max Altitude 4000m * Temperature at max Altitude Profile in Table 4-5 * Relative Humidity Profile in Table 4-5 * Length of time at Max Altitude 182 hrs Thanks in advance, Jeffrey Collins MTS, Principal Compliance Engineer Ciena Core Switching Division jcoll...@ciena.com www.ciena.com --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org -- Jon D. Curtis, P.E. Director of Engineering Curtis-Straus LLC One Stop Laboratory for NEBS, EMC, Product Safety, and Telecom Testing. 527 Great Road Littleton, MA 01460 USA Voice 978-486-8880 Fax 978-486-8828 email: jcur...@curtis-straus.com WWW.CURTIS-STRAUS.COM --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single
TCBs are designated
Telecom Certification Bodies have been designated by the FCC. Anyone who wants a copy of the public notice can email me as it does not seem to have appeared on the FCC web site yet. -- Jon D. Curtis, P.E. Certification Manager Curtis-Straus LLC Telecom Certification Body 527 Great Road Littleton, MA 01460 USA Voice 978-486-8880 Fax 978-486-8828 email: jcur...@curtis-straus.com WWW.CURTIS-STRAUS.COM
Employment opportunity
Are you searching for an exciting employment opportunity? Curtis-Straus, an Electronics Testing Laboratory in Littleton, MA is looking for EMC engineers to staff our test and design laboratory. Curtis-Straus LLC is the fastest growing testing laboratory in New England! We offer an entrepreneurial environment with unlimited growth opportunities. Curtis-Straus specializes in Electromagnetic Compatibility and Electromagnetic Interference (EMC/EMI) testing, NEBS testing, Product Safety testing and Telecommunications testing. Our ideal candidate will possess the following skills and qualities: Strong Technical Skills Talent for Solving Technical Challenges Strong Written and Verbal Communications Skills Must Enjoy Daily Client and Team Member Interaction Desire to Learn If you are looking for an opportunity to establish yourself as a future leader in a growing company, this may be your opportunity. Please forward or email your resume to: j...@curtis-straus.com Curtis-Straus LLC Attn: Dept. H 527 Great Road Littleton, MA 01460 -- Jon D. Curtis, P.E. Director of Engineering Curtis-Straus LLC One Stop Laboratory for EMC, Product Safety, and Telecom Testing. 527 Great Road Littleton, MA 01460 USA Voice 978-486-8880 Fax 978-486-8828 email: jcur...@curtis-straus.com WWW.CURTIS-STRAUS.COM --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Re: European Standards in conflict with the EMC directive
I suspect that given the group's proclivity to talk endlessly on almost any topic that the real reason that you got no response was that no one understood your question sufficiently to answer it. You obviously have an alarm system. You have some other EN standard which is in conflict with the alarm EMC standard. You have some authorizing bodies which don't accept your data. You are unhappy about the situation. What standard is in conflict with the alarm standard? Why is it being applied to your product? Does your product fall into multiple product families? What approvals are you approaching a certifier for? Who is the certifier? BTW: attempting to change the way CENELEC does business is futile. You will be attempting a remedy on government time frames for a problem with commercial time frames. You are advocating from a small constituency (alarm systems) against what is likely a larger constituency. Your best bet is to figure out what they want, the easiest way to do it, and give it to them. Kevin Harris wrote: Hello Again Group, Well the group's total silence on this point is indeed interesting. Does nobody know how to proceed or is everyone just keeping their corporate heads down : Please reply offline if you feel uneasy answering this question in a public forum. Regards Kevin Harris -Original Message- From: Kevin Harris [mailto:harr...@dscltd.com] Sent: Monday, November 08, 1999 10:38 AM To: EMC-PSTC (E-mail) Subject: European Standards in conflict with the EMC directive Greetings, Is there an established procedure for demanding the withdrawal of EMC clauses within standards who's primary purpose is industry regulation, not EMC. In my company's industry there is an established product family standard for EMC (EN50130-4) but the good people at CENELEC seem to be ignoring the EMC directive, and have published within the last year or two, EN standards which include EMC testing clauses, with methods that are at odds with the EMC document EN50130-4 published in the OJ. Especially troubling to me is the fact that all of the test organisations that test for the industry regulation specification do not accept either third party or self declarations that the product is EMC compliant. I do not wish to test the same product more than once for a single market. What path do you recommend I follow to demand the repeal of these clauses. Best Regards, Kevin Harris Manager, Approval Services Digital Security Controls 3301 Langstaff Road Concord, Ontario CANADA L4K 4L2 Tel +1 905 760 3000 Ext. 2378 Fax +1 905 760 3020 - - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, jim_bac...@monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators). -- Jon D. Curtis, PE Curtis-Straus LLC j...@curtis-straus.com Laboratory for EMC, Safety, NEBS, SEMI-S2 and Telecom 527 Great Roadvoice (978) 486-8880 Littleton, MA 01460 fax (978) 486-8828 http://www.curtis-straus.com - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, jim_bac...@monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
Re: Horn antennas, pre-amplifier, and return loss measurement
My higher horns came from Millitech. Leslie Bai wrote: EMCO has no horn over 40GHz. --- WOODS, RICHARD wo...@sensormatic.com wrote: Try EMCO for horns and MITEQ for preamps. -- From: Leslie Bai [SMTP:leslie_...@yahoo.com] Sent: Thursday, August 12, 1999 1:15 PM To: 'emc-p...@majordomo.ieee.org' Subject: Horn antennas, pre-amplifier, and return loss measurement Hi, Folks, Is there anyone can direct me to some sources of horn antennas preamplifiers. What I need are sets of horn antenna for spurious emissions testing to meet FCC Part 101. 1 to 18GHz, 18 to 26.5GHz, 26.5 to 40GHz, or 18 to 40GHz instead, 40 to 60GHz, 50 to 75GHz, or 40 to 75GHz instead, 75 to 110GHz, 110 to 170GHz, or 75 to 170GHz instead. Due to the significant space loss over 110GHz, I guess I also need a set of preamplifier from 110 to 170GHz. I am also studying on return loss measurement methodologies to meet ETSI requirement for radios RF port. Since NAMAS calibration of network analyzer may cost thousands bucks, I am wondering if I could achieve a good result (in terms of accuracy and uncertainty) using spectrum analyser and waveguide coupler. If anyone by any chance has an ready error model of the test setup using spectrum analyzer and waveguide coupler, I appreciate you could share with me to short my research path. Thanks in advance. Leslie Bai Senior Compliance Engineer Compliance Quality Manager Digital Microwave Corporation 170 Rose Orchard Way San Jose, CA 95134 Tel: (408)-944-1754 _ Do You Yahoo!? Get your free @yahoo.com address at http://mail.yahoo.com - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, jim_bac...@monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators). - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, jim_bac...@monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators). _ Do You Yahoo!? Bid and sell for free at http://auctions.yahoo.com - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, jim_bac...@monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators). -- Jon D. Curtis, PE Curtis-Straus LLC j...@curtis-straus.com Laboratory for EMC, Safety, NEBS, SEMI-S2 and Telecom 527 Great Roadvoice (978) 486-8880 Littleton, MA 01460 fax (978) 486-8828 http://www.curtis-straus.com - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, jim_bac...@monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
Re: Spam Mail
Hi Michael, (Disclosure: My company publishes Conformity Newsmagazine, a possible competitor with ITEM.) Something similar happened to one of my employees when they subscribed to ITEM. We didn't know what to do with all the stuff we got. I looked into it and found that there was a trick involved. On the ITEM subscription card it says FREE SUBSCRIPTION QUALIFICATION - Answer ALL questions in this section, below this is a list of stuff like Antennas with check boxes. Just above the check boxes it says FOR ADDITIONAL INFORMATION So, you check boxes about your interest to get a free subscription AND you also get tons of info from all the people that make the stuff for the boxes you checked. It could have been a confusing mistake in the way the form was put together, but I doubt it. In ITEMs defense, advertisers place way too much credence on how many leads they get back today. Most people who respond to an ad are wired in and either call the company direct or hit their web site rather than using the old, slow lead generation system. Companies that advertise need to qualify incoming leads by asking them where they came from when they come in by web or phone or fax or email. That's the only way they are going to figure out what advertising is working today. Most magazines are having to educate their advertisers to expect lower traditional lead generation and it must have been very tempting to juice the lead generation up. Michael Taylor wrote: Greetings All. I have recently been inundated with catalogues phone calls from vendors. After some sleuthing I discovered I had been slimed by one of the magazines we (all) receive. It appears they are attempting to increase there customer response index by sending advertisers false sales leads. In my case, vendors reported that I had responded via a Reader Response Card to recent ad's, which I had not. I am concerned enough about this practice to send this note. I believe that it represents the lowest form of deception and must be stopped. The magazine is free and performs a valuable service in keeping the EMC community informed. Vendors are nice enough to support this magazine through advertising. This symbiotic relationship benefits everyone as long as everyone plays by the rules. When I need information about I a product I expect to receive a prompt reply. With false leads vendors are needlessly burdened and replies take too long. Additionally, I got a note from the manager of our mail room about the extraordinary volume of mail I was receiving. The large number of voice mails from vendors overloaded the voice mail system. (I heard about that also). If any other members of the group have received the same treatment I urge you to contact the vendors and tell them you were slimed and inform the magazine you want it stopped. I'll step down from my soap box now and go lock myself in the chamber. Best Regards, Michael Taylor Principal EMC Engineer HACH Company - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, jim_bac...@monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators). -- Jon D. Curtis, PE Curtis-Straus LLC j...@curtis-straus.com Laboratory for EMC, Safety, NEBS, SEMI-S2 and Telecom 527 Great Roadvoice (978) 486-8880 Littleton, MA 01460 fax (978) 486-8828 http://www.curtis-straus.com - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, jim_bac...@monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
Re: EN 61000=4 again
Check the scopes. EN 300 386-2 is for the Central Office side of the demarkation point. It is for equipment which IS the network. That leaves EN55024 for equipment that is on the customer premise side of the demarkation point or is ITE that doesn't connect to the network. EN55024 is for telco terminal equipment. If your equipment goes in both places, test the extra non-overlap parts of the two standards and declare conformity to both. As for the generics, product family standards superceed the generics. For ITE that go in heavy industrial environments it may be appropriate to increase the levels of specific tests of EN55024 to the levels of EN50082-2 in order to prevent customer disatisfaction with your product, but you can CE mark your ITE for any environment with EN55024 alone. After all conflicting standards are withdrawn for EN55024 in 2001, it would be inappropriate to CE mark an ITE product based on test data to EN50082-2 alone. EN55024 has specific test configurations and among other things, extra surge tests to cover the special product family needs of ITE. Cal Whiteley wrote: Thanks to all of you for your info - but I'm still a bit confused Is the applicable standard for telecommunications terminal equipment EN 55024 or is it EN 300 386-2 ? It's my understanding that both standards cite EN 61000-4 sections but that there is a difference- EN 61000-4-8 is called out in EN 55024 but not in EN 300 386-2. Which is the applicable standard? - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, jim_bac...@monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators). -- Jon D. Curtis, PE Curtis-Straus LLC j...@curtis-straus.com Laboratory for EMC, Safety, NEBS, SEMI-S2 and Telecom 527 Great Roadvoice (978) 486-8880 Littleton, MA 01460 fax (978) 486-8828 http://www.curtis-straus.com - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, jim_bac...@monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
Re: EMC Books
Hi Ron, I've posted reveiws of a number of EMC books at www.conformity.com/book_store.html Disclosure: I also sell the books there. ron_pick...@hypercom.com wrote: To all, I am interested in knowing (and maybe others are, too) about the really good EMC books that are out and about. They may be practical, theoretical or anywhere in between. Areas of interest are, but are not limited to PWBs, backplanes and systems with considerations for design, troubleshooting, and noise reduction. For those having such handy references up on their shelves or just knowing of any, please feel free to reply. Replies may be either posted on this forum or sent to me privately. Either way, I will post the summary of results once the responses die off. BTW, I already know about a few books and will include those in the summary. This list of EMC references will likely be a valuable asset to any EMC professional, particularly those new to the game. Who knows, maybe we all might benefit from such a list. OK, let me have it/them. Best regards, Ron Pickard ron_pick...@hypercom.com - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, jim_bac...@monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators). -- Jon D. Curtis, PE Curtis-Straus LLC j...@curtis-straus.com Laboratory for EMC, Safety, NEBS, SEMI-S2 and Telecom 527 Great Roadvoice (978) 486-8880 Littleton, MA 01460 fax (978) 486-8828 http://www.curtis-straus.com - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, jim_bac...@monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
Re: 1000Base-T (IEEE 802.3ab) vs. EMI on UTP (Unshielded Twisted Pairs)
According to an artical by Lee Goldberg in Electronic Design November 16, 1998, Giga bit ethernet usesPAM-5 modulation scheme with a partial-response spectrum shaping of the form 0.75 + 0.25z(-1) to limit emissions to within the FCC limits. This simple filter shapes the spectrum so that its power spectral density falls below that of existing 100Bast T ethernet. Since 100BaseT is compliant, it is likely that Gigabit will be compliant. The magic is in the spreading algorithim which spreads the energy uniformly over a very broad range while maintaining the bipolar average. As far as I know, all ethernet standards incorporate these modulation schemes in order to comply when transmitted over unshielded cables. Since emissions are measured with a 120kHz bandwidth (from 30-1000MHz), you can pump out a lot of power if you spread it over a large frequency (say 100MHz). If the other end is intellegent enough to decode your scrambled bits, and you code for emissions reduction/spreading the result is communications at a high rate with emissions in compliance with the FCC limits. Donald Kimball wrote: The IEEE 802.3ab defines the new Gigabit Ethernet Standard (i.e. 1000Base-T). This Local Area Network (LAN) can use 4 twisted pairs of unshielded copper cable (Category-5) at 100m maximum operating at 250Mb/s per pair in full-duplex bi-directional mode. This standard is designed to utilize existing LAN cables such as older 10Base-T and 100Base-T networks. The signaling (i.e. baud) rate is 125MHz per pair using 5-level Pulse Amplitude Modulation (PAM) . This probably results in the fundmental energy at 62.5MHz given that the signal must be bipolar to be compatible with transformers. Vendors such as Broadcom Corp. have developed single chip copper cable interfaces for this new standard. In the past, standards using unshielded cables, such as 100Base-T, 10Base-T, T1, E1, etc, have had signaling rates less than 30MHz, so that the fundamental frequency was below the 30MHz FCC and CISPR starting frequency for radiated emissions. However, 1000Base-T has a 125MHz signaling rate. A common mode current of less than 10uA at 30MHz at 1/2 of wavelength can yield an emission level equal to or greater than the Class B level. In addition, the 4 twisted pairs are all phase locked to each other. The intentional differential mode current is about 10mA, so the trans hybrid balance needs to be better than 60dB. This is achievable with the hybrid at the component level, but not at the system level with 100m of Cat 5 cable attached. Conclusion, I think that 1000Base-T (IEEE 802.3ab) on unshielded Category 5 cable is doomed to fail EMI. Anybody ever try a test? Any other opinions? Don Kimball - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators). -- Jon D. Curtis, PE Curtis-Straus LLC j...@curtis-straus.com Laboratory for EMC, Safety, NEBS, SEMI-S2 and Telecom 527 Great Roadvoice (978) 486-8880 Littleton, MA 01460 fax (978) 486-8828 http://www.curtis-straus.com - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
Re: isopropyl alcohol
What if anything are laboratories doing to calibrate chemical solutions? Seems to me that as an ISO Guide 25 laboratory, an analysis of the batch of the solution to nationally tracible standards by an ISO Guide 25 laboratory is required. What are other laboratories doing to calibrate chemical solutions? Jon D. Curtis, PE Curtis-Straus LLC j...@curtis-straus.com Laboratory for EMC, Safety, NEBS, SEMI-S2 and Telecom 527 Great Roadvoice (978) 486-8880 Littleton, MA 01460 fax (978) 486-8828 http://www.curtis-straus.com On Fri, 10 Jul 1998, Chris Dupres wrote: Hi Ned. You wrote: I need some help to solve a difference of opinion. A number of standards require isopropyl alcohol for durability of marking test. e.g. IEC 1010-1, Clause 5.3 and IEC 601-1, Clause 6.1.z. The difference in opinion is in the concentration. The standards just state isopropyl alcohol. Some say 70% others say 100%. What are other people using? I use a material labelled 'Isopropyl Alcohol' for the rub test. That's what it says on the tin, and I can only assume that it is 100%. I am sure that it is 100% because spills evaporate very quickly and leave no water behind, I'm sure that if it was diluted the water would remain long after the IPA had gone. Does that make sense?. Chris Dupres Surrey, UK.
Re: Multiple EMC requirements for Fire Equipment in EU
For the standards route to compliance only standards listed in the OJ with reference to the EMC directive can be used. EN50130-4 is listed, EN54-2 is not. With regards to the EMC directive, EN50130-4 wins. You will still need to do what your customers want you to do and that may include EN54-2, but there is no need to do it under the EMC directive. I'd advise that you attempt to get them to accept EN50130-4 in leu of the immunity tests you describe. Jon D. Curtis, PE Curtis-Straus LLC j...@curtis-straus.com Laboratory for EMC, Safety, NEBS, SEMI-S2 and Telecom 527 Great Roadvoice (978) 486-8880 Littleton, MA 01460 fax (978) 486-8828 http://www.curtis-straus.com
Massachusetts jobs
HIRING EMC or Product Safety or SEMI S2 Engineers in Massachusetts Curtis-Straus, a progressive entrepreneurial test and design laboratory, is seeking engineers to join our team. Our requirements include strong technical skills, a talent for solving technical challenges, and strong communications skills. The ideal candidate will strive to assure client satisfaction and enjoy daily interaction with clients and team members. Send resume to Department T, Curtis-Straus, 527 Great Road, Littleton, MA 01460. Or use email to cs...@world.std.com. Web:http://www.curtis-straus.com/ Jon D. Curtis, PE Curtis-Straus LLC j...@curtis-straus.com Laboratory for EMC, Safety, NEBS, SEMI-S2 and Telecom 527 Great Roadvoice (978) 486-8880 Littleton, MA 01460 fax (978) 486-8828 http://www.curtis-straus.com
Recent EMC OJ standards list
The April 3, 1998 OJ notice listing all EMC standards and their dates of withdrawal has been posted on the Conformity web site. http://www.conformity.com Happy surfing. Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com Laboratory for EMC, Safety, NEBS, SEMI-S2 and Telecom 527 Great Roadvoice (978) 486-8880 Littleton, MA 01460 fax (978) 486-8828 http://world.std.com/~csweb
Job opportunities
HIRING Electrical Engineers in Massachusetts For EMC or Product Safety or SEMI S2 careers Curtis-Straus, a progressive entrepreneurial test and design laboratory, is seeking engineers to join our team. Our requirements include strong technical skills, a talent for solving technical challenges, and strong communications skills. The ideal candidate will strive to assure client satisfaction and enjoy daily interaction with clients and team members. Send resume to Department T, Curtis-Straus, 527 Great Road, Littleton, MA 01460. Or use email to cs...@world.std.com. Web:http://www.curtis-straus.com/ Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com Laboratory for EMC, Safety, NEBS, SEMI-S2 and Telecom 527 Great Roadvoice (978) 486-8880 Littleton, MA 01460 fax (978) 486-8828 http://www.curtis-straus.com/
Re: Canada CISPR 22 Conducted Emissions Answer
I think you overlooked a detail. The FCC allows you to use the LIMITS of CISPR 22, but requires the ANSI TEST METHODS with regards to cable manipulation, etc. Since the CISPR 22 techniques are relatively unspecified and are being modified in committee to match ANSI C63.4, a test report for all countries would use the CISPR 22:1993 limits and the ANSI test methods now. Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com Laboratory for EMC, Safety, NEBS, SEMI-S2 and Telecom 527 Great Roadvoice (978) 486-8880 Littleton, MA 01460 fax (978) 486-8828 http://world.std.com/~csweb On Thu, 19 Feb 1998 fryd...@norand.com wrote: Subject: Canada CISPR 22 Conducted Emissions Answer Author: frydave at NOR2CCPO Date:2/19/98 10:39 AM Thank you for all responses. Clarification for testing and report requirements. Based on the fact the European Union, FCC and Industry Canada have endorsed CISPR 22, a test report that covers Global requirements would be as follows. The following assumes the use of universal power supplies or supplies with 120-230 volt settings available. -Radiated emissions to CISPR 22-1993 using CISPR peripheral and cable maximization procedure. To satisfy the worst case requirements, investigative testing must be done at 120 VAC 60 Hz and 230 VAC 50 Hz. Perform final radiated emissions testing at the worst case operating voltage. Justify the operating voltage as the worst case configuration within the text of the report. -Conducted emissions is also done to CISPR 22 range of 150 kHz to 30 MHz and testing must be performed at both 120 VAC 60 Hz and 240 VAC 50 Hz. Again use the peripheral and cable maximization procedure for CISPR 22-1993. Report the conducted emissions for both voltage settings within the test report. Once the European Commission has adopted CISPR 22-1997, all testing will use the peripheral and cable maximization procedure outlined within the 1997 version, essentially the ANSI C63.4-1992 procedure. [hopefully Canada will also adopt the new CISPR 22-1997 requirements for maximization of cables and peripherals] Dave Fry, Sr. EMC Specialist Intermec Technologies Corporation Norand Mobile Systems Division EMC Test Laboratory Internet: fryd...@norand.com
Products outside LVD range
This one's more appropriate for the EMC-PSTC List :) -JDC. From: D. E. Smith desm...@amp.com Subject: Outside the LV Directive Range What do you do it your product has a working voltage outside the LVD range? While the LVD has a range of 50 to 1000 volts DC or 75 to 1500 volts AC a product like a high voltage test probe may not fall into this range because they measure voltages from 6 to 40 KV. What happens if someone would use one of these probes to test a circuit that falls within the LVD? Can we test to IEC 1010 Category III and if it passes can we claim compliance? RCIC - http://www.rcic.com Regulatory Compliance Information Center
Re: Lightning and Power Cross Testing
See remarks below. Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com One-Stop Laboratory for EMC, Product Safety and Telecom 527 Great Roadvoice (508) 486-8880 Littleton, MA 01460 fax (508) 486-8828 http://world.std.com/~csweb On Thu, 31 Jul 1997, Jerry Martin wrote: I've been asked to test a network powered (-130 Vdc) product to GR-1089-CORE for lightning and power cross. Does anyone out there have any suggestions on how to do this testing while the product is powered? The problem is that if you apply 1000 V, 10/1000 uSec, 100 A to tip/ring while the product is powered, you will damage the power source. I've looked into using series inductance followed by an MOV and capacitor, but I'm not sure if all the energy is getting to the UUT. Another problem is that my tester applies a short to tip and ring prior to the application of the test voltage. To protect the power supply add as much resistance as you can push the required amount of current through. Then add a 2-10mH inductor (you can buy commercial or cut up a line filter). Make the protection two pole with capacitors (5uF to ground ought to do) and non-linear with MOVs rated just over 130VDC. To keep the EUT running during the power supply shorting action use a large capactor in series with the generator. You'll need to use a fairly large one to avoid cliping the trailing edge of the short circuit current waveform. Without running calcs, I believe the ballpark is 1000uF for a 5-10% reduction in short circuit fall time. Hopefully, your generator is a little long so that you can shorten it down to 1000uS. The same problem doing power cross (600 Vac, 1 A, 1 Sec). Applying this kind of voltage to the power source will damage it. Is there a way for the UUT to remain line powered and provide protection to the power source? Seems to me you could use something like the loop simulator from part 68. Protect the DC power source with 10 Henry inductors in series with each lead. Check this out by placing a capacitor (say 1000uF) across the power supply end of the inductors (sans power supply) and measure the voltage on the cap with a volt meter (it ought to be real low). Be cautious with this set up because inductors with less than 1500V dielectric withstand capabilities are likely to become fire or fragmentation hazards. With Surge and Overvoltage testing eye protection is not optional. Has anyone had similar problems? Thank you very much for any suggestions. Jerry
RE: MDoC References to Harmonized Standards
Dear Tony, For ITE you should have on your MDoC: EMC Directive:89/339/EEC as Amended by 93/68/EEC EN55022:1994 and EN55022 A1:1995 for RF emissions EN50082-1:1992 or EN50082-2:1995 for immunity Low Voltage Directive: 73/23/EEC as Amended by 93/68/EEC EN60950 for safety and you might have: EN60555-2, EN60555-3, or EN61000-3-2 and EN61000-3-3 and any other standards or directives applicable to your specific product. Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com One-Stop Laboratory for EMC, Product Safety and Telecom 527 Great Roadvoice (508) 486-8880 Littleton, MA 01460 fax (508) 486-8828 http://world.std.com/~csweb On Wed, 4 Jun 1997, Tony Fredriksson wrote: Hi, Thumbing through Compliance Engineering Magazine, the 1996 Reference Guide, I note on page A8 that EN 55022:1994 was published in the OJ on September 16, 1995. That would mean that the Generic Emissions Standard, EN 50081-1:1992, should not be referenced on an MDoC for ITE, whereas EN 55022:1994 should be. This assumes that EN 55014, EN 60555-2, and EN 60555-3, the other standards referenced by EN 50081-1:1992 are not applicable to the ITE product in question. Am I interpreting this correctly? Thx, tony_fredriks...@netpower.com
Spread Spectrum Transmitter Approvals
Dear EMC-PSTCer's, I have a client who wants to obtain transmitter approvals in the following countries for the following transmitter types. If you have information or offer a service/testing please send me email. Thank you. The questions are: Is 433.92MHz narrowband allowed for short range transmitters? Is 2.44 GHz narrowband allowed for short range transmitters? Is 2.44 GHz spread spectrum allowed? What is the spread spectrum frequency range? Countries: Norway Japan South Korea Phillipines Israel Saudi Arabia South Africa Brazil Chile Austrailia Once again please reply to me and thanks. Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com One-Stop Laboratory for EMC, Product Safety and Telecom 527 Great Roadvoice (508) 486-8880 Littleton, MA 01460 fax (508) 486-8828 http://world.std.com/~csweb
Read any good (EMC) books lately?
I am conducting a search for good technical works. I am interested in articles, books and other publications which you might consider useful or otherwise state-of-the-art. I would particularly like to find works which support their thesis with experimental data. Please send recommendations directly to me. I will then post a compendium back to the group once the information is in. I am especially interested in the following subjects: Use of spread spectrum clocks for EMI reduction Measurement errors introduced by wooden frame EMI sites High speed multi-layer PCB layout strategies to minimize EMI Comparison of modern day logic families (ground bounce?) Software control of transient behavior introduced by EMC Hardening of thermocouple, RTDs, and other small signal circuits to withstand radio frequency interference. Thanks in advance for your cooperation. Best Regards, Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com One-Stop Laboratory for EMC, Product Safety and Telecom 527 Great Roadvoice (508) 486-8880 Littleton, MA 01460 fax (508) 486-8828 http://world.std.com/~csweb
re: Austrailian Immunity implementation date for ITE (fwd)
I asked the sma about immunity testing in Austrailia as part of the EMC framework and received the following reply. Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com One-Stop Laboratory for EMC, Product Safety and Telecom 527 Great Roadvoice (508) 486-8880 Littleton, MA 01460 fax (508) 486-8828 http://world.std.com/~csweb -- Forwarded message -- List-Post: emc-pstc@listserv.ieee.org Date: 1 APR 97 08:57:01 EST From: dbrum...@sma.gov.au To: j...@world.std.com Subject: re: Immunity implementation date for ITE Dear Jon Immunity is not required at this stage. We intend to require it in future for selected products that are particularly susceptible, but we have no implementation date as yet. David Brumfield Radiocommunications Standards Team dbrum...@sma.gov.au
Re: ICES-003
ICES-003 is very close to the FCC 47 CFR part 15 digital device emissions requirements. It is based on CSA C108.8 -M1983 test method and limits which are virtually identical to the FCC limits prior to the revision of 1989 (ie no limits above 1GHz). The test method also follows the old MP-4, but ANSI c63.4 techniques are compatible. IECS-003 is availible on the Industry Canada web site. Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com One-Stop Laboratory for EMC, Product Safety and Telecom 527 Great Roadvoice (508) 486-8880 Littleton, MA 01460 fax (508) 486-8828 http://world.std.com/~csweb On Wed, 19 Feb 1997, Vi Van (MEPCD) wrote: Dear All, Does anyone have any information regarding ICES-003? How is it different from FCC and CISPR22? Thanks in Advance. Vi Van Mitsubishi PC
RE:
I have tested systems to the heavy industrial immunity specification which included class B PCs. Both HP Vectra computers and Dell computers faired well. Ocassionally the monitors sold with these systems are disturbed to the point of turning themselves off (a failure in most books). To date I've always been able to solve this problem by upgrading to an NEC multisync monitor. The key distinquinction of all these products is that they really do meet class B by wide margins and use very good shielding to get to that level. Once you have shielding that good and use digital techniques inside (as opposed to small signal, high impedance analog signals - thermocouples, etc.) heavy industrial immunity compliance is usually a given. Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com One-Stop Laboratory for EMC, Product Safety and Telecom 527 Great Roadvoice (508) 486-8880 Littleton, MA 01460 fax (508) 486-8828 http://world.std.com/~csweb On Wed, 12 Feb 1997, Tony Fredriksson wrote: If such a system is not easy to find, is there any reason why one can't use two systems to test an expansion card? One could be CE marked and declared for Class B ( a PC) and the other could be a system that is CE marked and declared for Heavy Industrial Immunity. In this way, you have shown the card to be compliant with both standards and do not need to search for one system that has all of the approvals. Is this acceptable? Regards, tony_fredriks...@netpower.com -- From: comp_lab To: EMC-PSTC Date: Wednesday, February 12, 1997 2:38PM Hello All, We are doing something out of the usual for us and have developed a product that is a card designed to go in a PC. For our normal products, with regards to the EMC directive, we do industrial immunity and Class B for emissions. We would like to do the same for the PC card. The problem is I haven't found a PC yet, that has been previously tested to the industrial immunity standard AND class B. If anybody knows of any systems that will pass these tests please let me know. Thanks for your help Regards, - Kevin Harris Manager, Compliance Engineering Digital Security Controls Toronto, Canada 416 665-8460 Ext 378 -
Re: How the limits determined?
You need a copy of the FCC 79-555 report and order of 1979 implementing the regulation of digital devices. Appendix C is titled Derivation of Limit for Class B Computing Device. The class A limit was derived from CBEMA proposal CBEMA/ESC5/77/29 which was also submitted to CISPR. I would be willing to send you a copy of an exerpted FCC RO published in Dash's 1984 annual if you send me your fax number. Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com One-Stop Laboratory for EMC, Product Safety and Telecom 527 Great Roadvoice (508) 486-8880 Littleton, MA 01460 fax (508) 486-8828 http://world.std.com/~csweb On Tue, 14 Jan 1997, Tom Bao wrote: Can anyone give me some background or history information on how the radiated and conducted emission limits were determined by FCC and CISPR, in terms of the field strength level? Any research supports the limit level? Any input will be greatly appreciated. Regards, Tom http://www.rcic.com
Re: Measurement Uncertainty
Dear Hans, I know of no manufacturers actually engaged in series production audits. So lets hear from them. Please respond to this forum. The companies I work with look to CISPR 22 8.2.1.1 and test one sample. Some of them are happy with 0dB margin. I advise a higher margin, but they are responsible for signing the DoC. To date it would appear to me that the 80/80 rule only has a place in making it harder to take product off the market. You can go to market with only one sample tested, but if someone wants to restrict your access they have to perform an 80/80 rule statistical test to say you fail (CISPR 22 8.2.4). As a test lab, I'd love the 80/80 rule if the market would support it (three-five times the testing, yippee!). The doctrine also seems to need a bit of clarification: Xn is refered to as the value of the individual item. Is this the value of the one point closest to the limit? Can you change the frequency? On a product do you evaluate more than one frequency? How many? - the six closest to the limit? When doing more than one test, are several 80/80 tests performed - one for radiated, one for conducted? The 80/80 test is a statistician's dream and a test engineer's nightmare. Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com One-Stop Laboratory for EMC, Product Safety and Telecom 527 Great Roadvoice (508) 486-8880 Littleton, MA 01460 fax (508) 486-8828 http://world.std.com/~csweb On Mon, 13 Jan 1997 hans_mellb...@non-hp-santaclara-om4.om.hp.com wrote: I take exception with the statement passing is passing and failing is failing. CISPR 16 and 22(section 8.2.4) (maybe others too) require that during manufacturing sampling, the products pass the so called 80/80 rule. A minimum sampling of 3 units is required to perform this 80/80 calculation and products with minimal margin will discover that they fail the formula test! Go ahead and try a sample hypothetical test! __ Reply Separator _ Subject: Re: Measurement Uncertainty Author: Non-HP-owner-emc-pstc (owner-emc-p...@majordomo.ieee.org) at HP-Boise,mimegw2 Date:01/13/97 05:14 AM In the USA, NIST has published Technical Note 1297 1994 ed. Guidelines for Evaluating and Expressing the Uncertainty of NIST measurement results. Our NVLAP accreditation requires us to estimate uncertainties in our test reports. Every Curtis-Straus EMC or Telco test report contains uncertainty estimates. As to the passing margin, passing is passing and failing is failing. Before you take measurement uncertainty into the limit, first consider that technique has improved (and therefore unceratinty is lower) than it was when the limits were formulated. Second consider that the regulators which accepted the limit were well aware that uncertainty exists and in all likelyhood accounted for it in their choice of the limit. That said, I advise all clients who are within our uncertainty of the limit (but passing), that they should be aware that they may fail next time. If they are at the prototype stage, or building a product which will become the platform for future development, it is advisable to seek a larger margin. Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com One-Stop Laboratory for EMC, Product Safety and Telecom 527 Great Roadvoice (508) 486-8880 Littleton, MA 01460 fax (508) 486-8828 http://world.std.com/~csweb On Fri, 10 Jan 1997, Barge, Michael wrote: FROM: michael_ba...@atk.com Item Subject: Measurement Uncertainty Greeting Tregers; There seems to be a requirement that, when giving a measured value, there must be an uncertainty associated with that value describing the confidence of that value. (1) Do most labs report an uncertainty measurement in the test report, on the data sheet, on a certificate of compliance? (2) How did you generate the measurement of uncertainty for emission tests? For immunity tests? AND MOST IMPORTANTLY (3) What do you tell the customer when he is below the limit by less than the measurement uncertainty? When he is above by less? J Michael Barge Alliant Techsystems Annapolis, MD
Re: Measurement Uncertainty
In the USA, NIST has published Technical Note 1297 1994 ed. Guidelines for Evaluating and Expressing the Uncertainty of NIST measurement results. Our NVLAP accreditation requires us to estimate uncertainties in our test reports. Every Curtis-Straus EMC or Telco test report contains uncertainty estimates. As to the passing margin, passing is passing and failing is failing. Before you take measurement uncertainty into the limit, first consider that technique has improved (and therefore unceratinty is lower) than it was when the limits were formulated. Second consider that the regulators which accepted the limit were well aware that uncertainty exists and in all likelyhood accounted for it in their choice of the limit. That said, I advise all clients who are within our uncertainty of the limit (but passing), that they should be aware that they may fail next time. If they are at the prototype stage, or building a product which will become the platform for future development, it is advisable to seek a larger margin. Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com One-Stop Laboratory for EMC, Product Safety and Telecom 527 Great Roadvoice (508) 486-8880 Littleton, MA 01460 fax (508) 486-8828 http://world.std.com/~csweb On Fri, 10 Jan 1997, Barge, Michael wrote: FROM: michael_ba...@atk.com Item Subject: Measurement Uncertainty Greeting Tregers; There seems to be a requirement that, when giving a measured value, there must be an uncertainty associated with that value describing the confidence of that value. (1) Do most labs report an uncertainty measurement in the test report, on the data sheet, on a certificate of compliance? (2) How did you generate the measurement of uncertainty for emission tests? For immunity tests? AND MOST IMPORTANTLY (3) What do you tell the customer when he is below the limit by less than the measurement uncertainty? When he is above by less? J Michael Barge Alliant Techsystems Annapolis, MD
Re: Measurement Uncertainty
Response to Tony Fredriksson's comments: See below. Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com One-Stop Laboratory for EMC, Product Safety and Telecom 527 Great Roadvoice (508) 486-8880 Littleton, MA 01460 fax (508) 486-8828 http://world.std.com/~csweb On Mon, 13 Jan 1997, Tony Fredriksson wrote: Jon, Thanks for the info on the NIST Technical Note. Looks like I need to get a copy and undertand it. It is good to know that Curtis-Straus estimates uncertainty. I am particularly interested in the EMC side of the discussion and have a couple of questions: 1. In the case of Immunity, I suppose the lab would only be able to estimate uncertainty of the disturbance from the test generator. Is that correct? Wouldn't the loading of the signal source from EUT have a dramatic affect on the test result uncertainty? If this is the case, how is it factored in such that uncertainty of the end result is quantified to any practical degree? For radiated immunity, we do a Type B uncertainty evaluation on the test. We only consider the factors from the test equipment as we feel our uncertainty results from the level of the field without the EUT. The effects of the EUT on the field will vary by EUT (size, dimensional resonances, etc.) but between samples of individual EUTs these factors should be well behaved. We do ignore cable position as a factor, relying on the fact that we test 4 different sides in two polarities to give us some statistical protection in this area. The major contribution to uncertainty then becomes the leveling of the field which is +-3dB. Since this is a MUST be within 0dB to 6bB, we use Uj as 3dB and divide it by square root of three assuming a rectangular distribution. See the NIST note. 2. In the case of EMI, what is the range of uncertainty that one of your tests can provide? I would think it is a function of frequency. Does it attempt to take into account the uncertainty due to a change in cable or preripheral placement from one setup to the next of the exact same EUT? If so, how was that uncertainty derived? It could be a function of frequency. Certainly antenna factors and site anomalies are generally better behaved above 200MHz. To date we use a simple uncertainty using estimated worst case results across the frequency spectrum. As factors we have: antenna factor: +-1dB, NSA: +-4dB (ours is really max 2dB so we use +-4dB, but assume a traingular distribution on this factor), Equipment factors: SA flatness 1.5dB, cable calibration: .3dB, test method variance (cable manipulation: +-2dB, normal distribution). Add it up using Root-sum-of-squares=2.9dB uncertainty: Note that there are additional factors based on the assumed distributions of the uncertainties. The reason that I am curious about this is that I have seen some cables so hot (headphone on a CD ROM port for example) that moving them an inch or two in either direction can vary emissions by 10dB or more. That would seem to be quite unpredicatable by statistical methods and would seem to dwarf any uncertainties from other sources. This even considers test setup methods that have been designed to minimize test variation (such as ANSI C63.4). Yes, cable manipulation done properly is still the over-riding factor in repeatibility. I am able to obtain 2dB repeatibility with attention to cable manipulation to maximize emissions at each frequency. If you don't maximize the cables you will see variances of at least 10dB between EUT setups that appear identicle. I can see that using the lab's stated uncertainty in combination with a CISPR 16 style sampling test would be a significant improvement over other procedures. Thanks, tony_fredriks...@netpower.com -- From: Jon D Curtis To: Barge, Michael Cc: 'emc-p...@ieee.org' Subject: Re: Measurement Uncertainty Date: Monday, January 13, 1997 9:14AM In the USA, NIST has published Technical Note 1297 1994 ed. Guidelines for Evaluating and Expressing the Uncertainty of NIST measurement results. Our NVLAP accreditation requires us to estimate uncertainties in our test reports. Every Curtis-Straus EMC or Telco test report contains uncertainty estimates. As to the passing margin, passing is passing and failing is failing. Before you take measurement uncertainty into the limit, first consider that technique has improved (and therefore unceratinty is lower) than it was when the limits were formulated. Second consider that the regulators which accepted the limit were well aware that uncertainty exists and in all likelyhood accounted for it in their choice of the limit. That said, I advise all clients who are within our uncertainty of the limit (but passing), that they should be aware that they may fail next time. If they are at the prototype stage, or building a product which will become
Re: HELP: EMI - CFR 47 Exemption for Machine Controls ?
Dear George, Look in 47 CFR 15.103 Exempted Devices. You are refering to section (b) exempted from the technical requirements of part 15 are digital devices used exclusively as an electronic control or power system utilized by a public utility or in an industrial plant... Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com One-Stop Laboratory for EMC, Product Safety and Telecom 527 Great Roadvoice (508) 486-8880 Littleton, MA 01460 fax (508) 486-8828 http://world.std.com/~csweb On Tue, 7 Jan 1997 hans_mellb...@non-hp-santaclara-om4.om.hp.com wrote: Check 47 CFR part 2 sections 803, 805, 806, 807 and 809. Essentially if your ISM equipment is classified as a radio frequency device or digital device and not selling to the US goverment you must comply with the technical requirements of part 15, or part 18. Part 18 section 121 allows for exemptions for certain ultrasound and MRI equipment. Other than that, I'm certain you have to comply! Best Regards, Hans Mellberg __ Reply Separator _ Subject: HELP: EMI - CFR 47 Exemption for Machine Controls ? Author: Non-HP-owner-emc-pstc (owner-emc-p...@majordomo.ieee.org) at HP-Boise,mimegw2 List-Post: emc-pstc@listserv.ieee.org Date:01/06/97 04:33 AM Dear Compliance Collegues CFR47 sets emission limits for digital devices. As far as I know there is or there was an exemption for machine controls, i.e. there are no emission limits for industrial machines ( I am not referring to ISM as defined by 47CFR18) I can not find this exemption in the 1993 edition of the CFR 47. Can anybody point me the ºº of CFR where this exemptions or was mentioned ? Thanks in advance George * Dr. Georg M. Dancau* HAUNI MASCHINENBAU AG * * g.m.dan...@ieee.org* EMC Lab * * TEL: +49 40 7250 2102 * Kampchaussee 8..32 * * FAX: +49 40 7250 3801 * 21033 Hamburg, Germany * * home: Tel: +49 40 738 51 07* Lohbruegger Landstr. 82 * * Fax: +49 40 730 11 99* 21031 Hamburg, Germany *
Medical Device Discussion Group
I thought TREG is such a good idea for telecom devices, why not one for medical device regulatory information? Thus MEDIC, the MEdical Devices Information Consortium ... to subscribe send subscribe medic to majord...@world.std.com. To contribute, members may send messages to me...@world.std.com. Info on MEDIC: Welcome to the home of me...@world.std.com, the Medical Devices Information Consortium, an established discussion group on medical devices regulations. Medical Devices Information Consortium (MEDIC) == Charter and Guidelines 10 December 1996 MEDIC is an informal group of people interested in medical device regulations and standards world-wide, networked electronically by mailing list. Its purpose is to provide a forum for the sharing of public, but esoteric or possibly obscure medical device compliance information, or related information with limited natural distribution. Members need only send contributions to: me...@world.std.com All mail sent to this Internet address will be immediately echoed to everyone on the MEDIC list by an automated list server. SUBSCRIBING OR UNSUBSCRIBING - Send an Internet e-mail request with the phase subscribe medic or unsubscribe medic in it to: majord...@world.std.com DISCLAIMER: MEDIC postings are the sole responsibility of the message originators. Jon Curtis does not assure the correctness or viability of any information distributed by the MEDIC list server, nor accepts any responsibility for the use of any MEDIC distributed information. MESSAGE CONTENT GUIDELINES: 1. Correspondence should be limited to information or queries relating to medical device regulations or standards only. Shared information should not be confidential or in any way proprietary. Please don't use the MEDIC for simple correspondence - Private correspondence should be addressed directly, unless it has broad appeal or interest. 2. Blatant or overt advertising of goods or services is not permitted. The MEDIC list server is provided as a service by Jon Curtis, whose policies prohibit anything that might be construed as conflict of interest. Exceptions: a) Short, non-promotional trailers or signature lines for the sole purpose of identifying the sender and the sender's organization. b) Answers to queries about goods or services, where the intent of the answer is to inform, but not promote. (When in doubt, send the questioner a private message.) c) This guideline is specific to the use of the MEDIC list server, and in no way inhibits individuals from contacting MEDIC members privately and independently. 3. Posting of medical device job openings is OK so long as they are short (i.e., 1 paragraph), non-commercial (no agencies or headhunters - no fees involved), infrequent (about one out of every 10 messages or less), and contain an off-MEDIC contact name and phone number or e-mail address. Same goes for jobs-wanted (if you can fit your resume into one paragraph!). 4. Using key words in the title or subject line will assist members who archive the message traffic and may wish to search it later. Suggested keywords include: CUSTOMIZED or DIAGNOSTIC or a country name (where the information is country-specific). 5. Queries or requests for information should be focused and brief. Respondents should be careful about endorsements - When in doubt, don't. HISTORY: MEDIC was started by Jon Curtis at Curtis-Straus LLC on 8 December 1996. QUESTIONS?: Send email to Jon Curtis at: medic-ow...@world.std.com Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com One-Stop Laboratory for EMC, Product Safety and Telecom 527 Great Roadvoice (508) 486-8880 Littleton, MA 01460 fax (508) 486-8828 http://world.std.com/~csweb
RE: EU Modem Approvals
From: Rene Debets rene_deb...@msn.com Message-Id: upmail07.199609201009120...@msn.com To: t...@world.std.com Subject: RE: EU Modem Approvals Dear Duane, No, it's not legal to use a modem in any other country than the one it is approved for. It doesn't even matter whether it does happen to meet the requirements Best regards, Rene -- From: treg-appro...@world.std.com on behalf of Duane J Marcroft Sent: Thursday, September 19, 1996 10:29 PM To: t...@world.std.com Subject:EU Modem Approvals Hi Treg'rs I have a question, if anyone could answer it I would appreciate it. I know rsNTR 21 has not been approved. But, if I design the DAA per NET 4 or rsNTR 21 for say the U.K. is it legal to use the modem in any other country? I'm not asking if it can sold in any other country, just if it can be legally carried to another EU country and used. I've read the verbage dealing with this point, but I'm still not clear if this the case. Thank you in advance. Regards, Duane Marcroft Telecom Consultant
Re: HP App Note
App note number on the front cover is 1273, but if you call HP they probably will not be able to track it by that... You need the number off the rear cover: 5964-1917E. I don't know about the web site. Try the plain ol' phone at 1 800 452 4844. Jon D. Curtis, P.E. Director of Engineering email: j...@world.std.com Curtis-Straus LLCphone: (508) 486-8880 527 Great Road fax:(508) 486-8828 Littleton, MA 01720 http://world.std.com/~jdc/ USA On Mon, 24 Jun 1996 j...@bangate.compaq.com wrote: Good Morning, I recently saw in a trade magazine an announcement that Hewlett Packard had an app note avaliable that dealt with designing and measuring power supplies to the requirements of IEC 555 (harmonics, fluctuations etc.). Does anyone know the app #, and if it is avaliable from HP via it's www page ? Thanks all, Jerry F.
Specs for Brazil, Mexico
From: rgu...@anonymous.com Subject: Specs for Brazil, Mexico Suggest you contact Certelecom Laboratories by phone or fax or E-Mail with what you want. They have a library of standards and approval forms. Apparently this includes the standards for Mexico and Brazil. Certelecom is a member of the CCT committees for NAFTA and holds the chair of the conformity Assessment Group. Phone is 1-800-563-6336, Fax is 1-613-737-9691. They have a home page on Internet and are a division of the British test lab KTL. RCIC Guest rgu...@anonymous.com Courtesy of RCIC http://uc.com/compliance_engineering/
Re: More on Competent Bodies
See below. Jon D. Curtis, P.E. Director of Engineering email: j...@world.std.com Curtis-Straus LLCphone: (508) 263-1897 409 Massachusetts Avenue fax:(508) 263-4164 Acton, MA 01720 http://world.std.com/~jdc/ USA On 5 Jun 1996, rbusche wrote: For some reason, it is still unclear in my mind the role of a competent body in the big picture. I have thrown out several topics for discussion on this, yet, the answer still somewhat eludes me. Please bear with me as I ask this question one last time. If company A in Europe buys a product from company B in the US, and the product is delivered with a CE Mark on the device(s). (Of course with the DoC accompanying the mark). Shouldn't company A be allowed to determine if the equipment suits them for their application AND shouldn't company A be able to accept whatever equipment they want WITHOUT a competent body involved? Yes, but... for emissions they must choose an approved standard. This is to prevent interference to a third party (company C) outside the transaction. For immunity, a standard must also be picked. BUT, company A could accept that Company B writes in it's manual that the product's performance is unknown and possibly horrible under ESD, EFT, RFI, etc. (why company A would accept substandard immunity is still an issue) Remember, under the performance criteria of the generic immunity documents, Company B is representing that their product performs as specified in the manual under EMC disturbances. The immunity side of the EMC directive can be looked at as setting up a covenant between the transacting parties. In the absense of further agreements, Company A has reason to believe that Company B's product operates as stated in the manual under a suite of electromagnetic disturbances defined by the standards as applicable to the expected end-use environment. I understand that if no standard exists or has been officially published in the OJ, a competent body might be useful. Right. But there are currently very few areas under the EMC directive that are not covered by the standards route. In fact, since the generic documents for immunity and emissions are published there is always a standards route to compliance. Only where the standards route is particularly onerous and you can convince a competent body to go easier on you, does the TCF route for the EMC directive make any economic sense at all. In my experience, rather than interpreting EMC regulations in a rational manner to minimize the required testing, competent bodies tend to test to everything they can find that might be applicable including draft standards not yet even published! But in my scenario, I am providing ITE equipment to a larger system which is arguably in this gray area. If your customer says you need to go the TCF and you can't convince him otherwise, you'll need a TCF to get the sale. Make sure he pays for it! Even here I have some concerns. The final application is a flight simulator with hydraulic motion platforms, displays, and computer systems. It is not obvious to me that this is justification for hiring a competent body to evaluate EMC performance. The only justification is based on your customer's lack of trust in you or the lab you contract to do the testing. There is no requirement in law for you to get a TCF from a competent body. The issue of light industrial Vs heavy industrial in my mind is one of ruggedization for the effects of EMC. Given that EN55022 defines the environment for a Class A emission device, the generic immunity standard EN50082-X should be a customers decision. This is a non-issue as relates to competent bodies. The standards route is open for both light and heavy industrial products. I agree that you should be able to pick either or as long as you document your decision in your specifications to the customer. You are responsible for defining the environment in which you intend your product to be used. Please excuse me if this is a dumb question, but if someone can shed a bit more light I promise to shut up on this issue. Thanks in advance Rick Busche rbus...@es.com
Re: Dates on MDoC
The requirement for date coding the Declaration of Conformity (DoC) under the Low Voltage Directive is contained in Directive 93/68/EEC. This directive modifies the CE marking scheme contained in many directives and adds CE marking to the Low Voltage Directive 73/23/EEC. For the Low Voltage Directive specifically, it adds, The EC declaration of conformity must contain the following elements: -the last two digits of the year in which the marking was affixed. I think your reading material may be a little confused. The declaration of conformity applies to a single item of your production. Therefore the date on it will change as different units of the product are marked at diferent times. Thus consumer confusion as to which standards were used to approve the product should be minimized as the standards applied will always be those in force when the CE marking is applied. Unless your distribution channel is years long, the consumer will always be getting product with a current date on it. Jon D. Curtis, P.E. Director of Engineering email: j...@world.std.com Curtis-Straus LLCphone: (508) 263-1897 409 Massachusetts Avenue fax:(508) 263-4164 Acton, MA 01720 http://world.std.com/~jdc/ USA On Fri, 26 Apr 1996 w...@dolby.com wrote: Folks, Various bits of literature I have here state that, with respect to the LVD, our Declaration of Conformity must show the year that the CE mark was first applied to the product. Can anyone tell me where in the official documents this is shown as a requirement? Seems to me that this could be confusing to a customer if the standards are changed/or updated. Thanks in advance, Bill Wray Dolby Labs San Franciso
Re: FCC 47 CFR Indust Equip
Section 15.103(b) CFR 47 (Exempted devices) exempts A digital device used exclusively as an electronic control or power system ... in an industrial plant from complying with the technical requirements of Subpart B. This means you don't have to do any testing and you do not need to label your product. You are however still subject to Part 15, specifically section 15.5 which requires you to correct any interference to licensed radio transmissions that your product causes in the field. Also, under section 15.29 you will need to comply with any commission request to evaluate your product (extremely unlikely, bordering on winning the lottery without betting). The legal issues aside, you may still wish to test your products for marketing reasons. You may find compliance with the FCC limits to be a selling feature for your equipment. If you are meeting the European requirements, compliance with the FCC limits should be almost automatic, in fact the same test data can usually used to show compliance with both the FCC and European specs. Finally, the FCC reevaluates the exemptions on about a ten year cycle. Right now they recommend that your class of products comply with the technical requirements. Someday the FCC might extend coverage to your equipment. Jon D. Curtis, P.E. Director of Engineering email: j...@world.std.com Curtis-Straus LLCphone: (508) 263-1897 409 Massachusetts Avenue fax:(508) 263-4164 Acton, MA 01720 http://world.std.com/~jdc/ USA On Wed, 24 Apr 1996 m_sher...@delphi.com wrote: We're a manufacturer of industrial equipment. The equipment goes into what the European EMC directive would classify as a heavy industrial environment. We use a lot of electronics--PCs, PLCs, sensors, etc--in our controls that are built into this equipment. Question: do we have to comply with the FCC regs, Title 47 CFR 15, subpart A (b), as an unintentional radiator? thanks! Mike Sherman Product Safety Engineer FSI International (612) 361-8140 m_sher...@delphi.com
Re: FCC Website Information
As to item 2 on the part 68 leakage test: It is a highpot type test. The idea is to see if hazardous currents from the AC power mains can reach the telco interface. The isolation is tested in two places: Once by placing 1000VAC between Tip/Ring and a long list of other parts of the product (which in most cases can be simplifed to logic ground). Second by placing 1500VAC between the AC mains inlet and a somewhat shorter list of parts of the product (also generally simplified to logic ground). In each case no more than 10mA of current can flow. The voltage is ramped to peak over 30 seconds and then maintained for another 60 seconds. Note that intentional paths to ground such as MOVs and spark gaps are removed for the test. If you have more questions or desire greater detail please feel free to call. Jon D. Curtis, P.E. Director of Engineering email: j...@world.std.com Curtis-Straus LLCphone: (508) 263-1897 409 Massachusetts Avenue fax:(508) 263-4164 Acton, MA 01720 http://world.std.com/~jdc/ USA On Wed, 24 Apr 1996, Larry Merchell wrote: 1. For Everyones Information, CFR's can be downloaded from (via Netscape): Federal Communication Commission Office of Engineering and Technology FCC Rules and Regulations located at: http://www.fcc.gov/oet/info/rules/ 2. I am looking for information regarding 47 CFR 68.304 Leakage current limitations. The standard states that the leakage current must be less that 10mA at 1500VAC from AC line to case [ (b) to (c) ], which looks like a Hipot test not a leakage test. Does anyone have any additional information regarding this? Thank you for any help. Larry Merchell Product Safety Engineer Xentek Power Systems lar...@electriciti.com
