Re: The Trouble with Convention, The Final Chapter
Following your logic, "I was just following orders," means that those who use an average detector on an EMI receiver or who properly use a spectrum analyzer to average as I demonstrated are at a competitive disadvantage to those who use bad math and give themselves twice the dB relaxation warranted. The proper response is to do the job right and so notify the customer so that he imposes the correct requirements even handedly. -- >From: umbdenst...@sensormatic.com >To: emc-p...@majordomo.ieee.org, dmck...@corp.auspex.com, ken.ja...@emccompliance.com >Subject: RE: The Trouble with Convention, The Final Chapter >Date: Tue, Oct 30, 2001, 4:13 PM > > The point! We have all missed the point! :-) > > I do not dispute the science. > > The question was not "what is the correct science", rather, "what is > expected by the FCC (or any other spectrum authority) for successful > processing of the submittal. It became apparent that the science did not > match the requirements. Is the requirement scientifically pure and > correct? -- no. Is the requirement specified? -- yes. > > I noticed no one commented on the impedance of free space in the far field > specified for use in the reactive near field given as another example of > "convention". Again is the convention correct? -- no. Specified? -- yes. > > Submittal convention is not about correct application of science; it's about > following specified rules, for whatever the reasons. The reasons usually > have to do with simplifying the submittal process while providing repeatable > results, this being more important than totally correct science. Allowances > have been made for the lack of perfect science. > > As a partial explanation of the origin of the current instruction being > debated, the following is an excerpt from another response regarding duty > cycle reporting for a Part 15.209 device: > >> the FCC reviewer had explained to me that he had problems >> > in the past with the interpretation by applicants for using averaging >> detectors so he preferred to mathematically arrive at >> > the average voltage. He asked for the peak detector output in units of >> uV to be multiplied >> > by the duty cycle to provide the "mathematical equivalent >> > of the average detector" in his words. I have been doing this ever >> since >> > for various reviewers and no submissions have come back. >> > 2.38 mV pk detector, 0.5 duty cycle on an average detector = 1.66 mV > per vbw averaging per the experiment in this thread below. > > 2.38 mV x 0.5 (duty cycle) = 1.19 mV per the mathematical process > specified. > > The 2 methods are clearly not equivalent. But FCC convention requires me to > submit "1.19 mV" data, which is also arrived at by the 20 log() operation > (hence the confusion about the sanity check earlier). I don't create the > convention; I just follow the submittal instructions (requirements). > > It is always good to have the correct science at your fingertips, but in the > end providing what is requested is what counts. For those still in the dark > about 20 log () or 10 log (), my suggestion is to go straight to the source > -- ask the FCC what they specify for your situation. > > > Don Umbdenstock > Sensormatic > > >> -- >> From: Ken Javor[SMTP:ken.ja...@emccompliance.com] >> Sent: Monday, October 29, 2001 2:41 PM >> To: umbdenst...@sensormatic.com; emc-p...@majordomo.ieee.org; >> dmck...@corp.auspex.com >> Subject: The Trouble with Convention, The Final Chapter >> >> In the face of all the responses I and others gave last week showing the >> MATHEMATICAL RULES for calculating logarithms and average and peak power, >> and the rationale and math behind pulse desensitization calculations, >> apparently it is still not clear that power is averaged, not potential. >> In >> the interest of stopping the flow of incorrect test reports to the FCC and >> their apparent approval, I submit the following, "A single test is worth a >> thousand expert opinions." For those who are confused and don't know what >> to believe, here is the simple test. I have run it and have pix of the >> spectrum analyzer display I can send to those who are interested (no >> attachments allowed on general mailings). >> >> Tune an rf source and your spectrum analyzer to a common frequency, say 10 >> MHz. Set up a baseline rf output, say -40 dBm. Use linear mode on your >> analyzer with a reference level of -37 dBm. Measure in peak detect mode >> (vbw greater than or equal to rbw). Measure again while averaging, using >> a >> 300 Hz vbw. You will get the same result. Apply a 50% duty cycle pulse >> modulation at 1 kHz. Peak detect will show the same -30 dBm, but video >> averaging will show a 3 dB decrease to -33 dBm. Try it - I did and it >> works. On the analyzer I used, linear mode defaults to a millivolt >> reading. >> I got 2.38 mV in peak mode, 1.66 mV in average mode - you do the math. >> >> >> >> -- >> >From: umbdenst...@sensorm
Re: one more thing about duty cycle... Dimensional Analysis .. but 11 fingers makes it tricky
Same exact equation, but the log reference would have been 11, or more properly, 10 base 11. -- >From: "Gregg Kervill" >To: "'Stuart Lopata'" , "'emc'" >Subject: RE: one more thing about duty cycle... Dimensional Analysis .. but 11 fingers makes it tricky >Date: Tue, Oct 30, 2001, 2:33 PM > > > Now that the dust on this one has settled - my trick is to start from first > principles with a spot of dimensional analysis. > > A ratio is dimensionless - therefore it is straight decibels and 10log. > > No convention - that is the definition. > > > > One of the few exceptions are Power. > > Power = k x V^2 > > Log(10) Power = K + 2 x log(10)V > > dB = 10xLog (10) Power = 10(K) + 20Log(10)V > > > But then I'm only a product safety engineer, so I'll leave the follow-on > question to you EMC types... > > Silly question though - what would be the equation have been if we had 11 > fingers? :^ ] > > > > Gregg > > > Eurolink Ltd. -One Link-199 Countries > P.O. Box 310 > Reedville, Virginia 22539 > Phone: (804) 453-3141 > Fax: (804) 453-9039 > Web:www.eu-link.com > > > > > --- > 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: > No longer online until our new server is brought online and the old > messages are imported into the new server. > --- 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: No longer online until our new server is brought online and the old messages are imported into the new server.
FW: EMCS Chapter Meeting Nov.1,2001 Cancelled
For Central New England EMC Chapter members - URGENT- Subject: EMCS Chapter Meeting Nov.1,2001 Cancelled Due to circumstances,The meeting scheduled for Thursday November 1,2001 at EMC Corporation has been cancelled. The following announcement is in the IEEE Boston Section REFLECTOR November 2001 issue: "Unusual Sources of Power Supply Noise" Speaker: Douglas C.Smith,Independent Consultant,Distinguished Lecturer EMC Society If this meeting is rescheduled,it will be announced in a future issue of the REFLECTOR. John M.Clarke, Chair CNE Chapter/ Boston Section, IEEE EMC Society Sent for John Clark - Boris Shusterman EMC Corp., Compliance Engineering 65 South St., Hopkinton, MA 01748 tel. (508) 435-2075 ext. 77517
NVLAP vs A2LA
Members, I have received quite a number of responses from memebers of this group. Comments from test labs, assessors, and even accreditors, are truely valuable, informative, and deemed sufficient for me to make a decision. Please understand that I couldn't reply each of your emails but I would like to take this chance to express my great appreciation to those who have contributed your input. Please be rest assured your comments would be kept confidential. Once again, thank you all. Leslie __ Do You Yahoo!? Make a great connection at Yahoo! Personals. http://personals.yahoo.com --- 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: No longer online until our new server is brought online and the old messages are imported into the new server.
RE: The Trouble with Convention, The Final Chapter
The point! We have all missed the point! :-) I do not dispute the science. The question was not "what is the correct science", rather, "what is expected by the FCC (or any other spectrum authority) for successful processing of the submittal. It became apparent that the science did not match the requirements. Is the requirement scientifically pure and correct? -- no. Is the requirement specified? -- yes. I noticed no one commented on the impedance of free space in the far field specified for use in the reactive near field given as another example of "convention". Again is the convention correct? -- no. Specified? -- yes. Submittal convention is not about correct application of science; it's about following specified rules, for whatever the reasons. The reasons usually have to do with simplifying the submittal process while providing repeatable results, this being more important than totally correct science. Allowances have been made for the lack of perfect science. As a partial explanation of the origin of the current instruction being debated, the following is an excerpt from another response regarding duty cycle reporting for a Part 15.209 device: > the FCC reviewer had explained to me that he had problems > > in the past with the interpretation by applicants for using averaging > detectors so he preferred to mathematically arrive at > > the average voltage. He asked for the peak detector output in units of > uV to be multiplied > > by the duty cycle to provide the "mathematical equivalent > > of the average detector" in his words. I have been doing this ever > since > > for various reviewers and no submissions have come back. > 2.38 mV pk detector, 0.5 duty cycle on an average detector = 1.66 mV per vbw averaging per the experiment in this thread below. 2.38 mV x 0.5 (duty cycle) = 1.19 mV per the mathematical process specified. The 2 methods are clearly not equivalent. But FCC convention requires me to submit "1.19 mV" data, which is also arrived at by the 20 log() operation (hence the confusion about the sanity check earlier). I don't create the convention; I just follow the submittal instructions (requirements). It is always good to have the correct science at your fingertips, but in the end providing what is requested is what counts. For those still in the dark about 20 log () or 10 log (), my suggestion is to go straight to the source -- ask the FCC what they specify for your situation. Don Umbdenstock Sensormatic > -- > From: Ken Javor[SMTP:ken.ja...@emccompliance.com] > Sent: Monday, October 29, 2001 2:41 PM > To: umbdenst...@sensormatic.com; emc-p...@majordomo.ieee.org; > dmck...@corp.auspex.com > Subject: The Trouble with Convention, The Final Chapter > > In the face of all the responses I and others gave last week showing the > MATHEMATICAL RULES for calculating logarithms and average and peak power, > and the rationale and math behind pulse desensitization calculations, > apparently it is still not clear that power is averaged, not potential. > In > the interest of stopping the flow of incorrect test reports to the FCC and > their apparent approval, I submit the following, "A single test is worth a > thousand expert opinions." For those who are confused and don't know what > to believe, here is the simple test. I have run it and have pix of the > spectrum analyzer display I can send to those who are interested (no > attachments allowed on general mailings). > > Tune an rf source and your spectrum analyzer to a common frequency, say 10 > MHz. Set up a baseline rf output, say -40 dBm. Use linear mode on your > analyzer with a reference level of -37 dBm. Measure in peak detect mode > (vbw greater than or equal to rbw). Measure again while averaging, using > a > 300 Hz vbw. You will get the same result. Apply a 50% duty cycle pulse > modulation at 1 kHz. Peak detect will show the same -30 dBm, but video > averaging will show a 3 dB decrease to -33 dBm. Try it - I did and it > works. On the analyzer I used, linear mode defaults to a millivolt > reading. > I got 2.38 mV in peak mode, 1.66 mV in average mode - you do the math. > > > > -- > >From: umbdenst...@sensormatic.com > >To: emc-p...@majordomo.ieee.org, dmck...@corp.auspex.com, > ken.ja...@emccompliance.com > >Subject: The Trouble with Convention > >Date: Mon, Oct 22, 2001, 4:46 PM > > > > > Similarly, it appears the same issue of convention is the basis of > certain > > FCC clauses, for example, the reporting of the output of an averaging > > detector as called for by 15.209 and other clauses for some frequency > bands. > > The FCC is looking for field strength, a voltage representing the output > of > > the averaging detector. The FCC is aware that there are different > > implementations of "averaging" detectors and linearity issues so they > > provided instructions to arrive at the reporting level by mathematical > means > > for consi
RE: one more thing about duty cycle...
Who is the final authority? It would seem to me that this would be the one who wrote the rules -- the FCC. So if you are audited and questioned about the correct handling of factors, you merely produce the FCC generated instructions and show that you comply with the instructions. End of issue. After all, a TCB is an extension of the FCC. Best regards, Don Umbdenstock Sensormatic > -- > From: Stuart Lopata[SMTP:stu...@timcoengr.com] > Reply To: Stuart Lopata > Sent: Tuesday, October 30, 2001 10:27 AM > To: emc > Subject: one more thing about duty cycle... > > > I found the reference that used 20log() for the correction factors. > > TCB Training > Unlicensed Devices > Part I > Richard Fabina > > This was given to us by the FCC for training our TCB people and part of a > TCB training course at NIST. > > I agree that the correction factor should be 10log(), but would like to > see > a confirmation from the actual certifiers. > So who is the final authority? > > Sincerely, > > Stuart Lopata > > > > > --- > 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: > No longer online until our new server is brought online and the old > messages are imported into the new server. > --- 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: No longer online until our new server is brought online and the old messages are imported into the new server.
Re: EN 55022 limits
I read in !emc-pstc that Stuart Lopata wrote (in ) about 'EN 55022 limits', on Tue, 30 Oct 2001: >The radiated limits are stated for 10 meters but our measurements are at 3 >meters. Is it ok to use 3 meter data and what should the new limits be (may >be 10 dB higher)? You need to look in the standard to see if that is allowed. If it is allowed, the 10 dB factor is to be used, but measurements at 10 m are definitive. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Eat mink and be dreary! --- 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: No longer online until our new server is brought online and the old messages are imported into the new server.
Re: reverb chamber test set up question
An excellent question! I can't say conclusively but this is gut feel. In a reverb chamber any metallic ground plane acts as a boundary and in the immediate vicinity an EM wave polarized parallel to that surface will be attenuated. Hence the restriction you noted. But the attenuation near the plane to which the EUT is bonded is allowed to attenuate horizontal polarization - because that is expected in the actual installation. That is also why the field sensors for RS103 are mounted 30 cm above the ground plane, to allow for the natural attenuation of horizontally polarized waves near the ground plane. So I would say that cable layout for a reverb chamber test should be no different than in anechoic chamber. And for a reverb chamber in particular, I would say that ground plane size has no effect, the field would not be diminished more in the center than near the edges. It may well be that cable rf pick-up efficiency is diminished relative to those within 10 cm of the edge, but that effect would be even more pronounced in a traditional test where the field would diminish in intensity as you moved further and further back from the transmit antenna. -- >From: "Ken Javor" >To: emc-p...@ieee.org >Subject: reverb chamber test set up question >Date: Sat, Dec 16, 2000, 8:30 PM > > Dear Colleagues, > > MIL-STD-461 requires cables to be laid out within 10 cm of the front edge of > the ground plane, which standardizes both RE efficiency and RS coupling. > How about for a reverb test? Is it as important for cables to be near the > ground plane edge, or can they be routed anywhere? Corollary: In a reverb > chamber EUT is not placed near wall as per -461, it is placed away from wall > to guarantee that max field intensities will develop in its vicinity. What > is effect of large ground plane (one twice the mil-std ground plane depth > or more)? Does this diminish field significantly around itself? > > Thank you. --- 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: No longer online until our new server is brought online and the old messages are imported into the new server.
Central New England EMC Chapter - EMCS Chapter Meeting Nov.1,2001 Cancelled
For members of Central New England EMC Chapter - Chapter Meeting Nov.1,2001 is Cancelled The meeting scheduled for Thursday November 1,2001 at EMC Corporation has been cancelled. The following announcement is in the IEEE Boston Section REFLECTOR November 2001 issue: "Unusual Sources of Power Supply Noise" Speaker: Douglas C.Smith,Independent Consultant,Distinguished Lecturer EMC Society If this meeting is rescheduled,it will be announced in a future issue of the REFLECTOR. Posted for John M.Clarke, Chair CNE Chapter/ Boston Section, IEEE EMC Society Boris Shusterman EMC Corp., Compliance Engineering 65 South St., Hopkinton, MA 01748 tel. (508) 435-2075 ext. 77517
SV: EN 55022 limits
Yes, as far as I know, when doing 3m measurements you increase the limits by +10dB (as long as the limits are refered to 10m measuements), Amund -Opprinnelig melding- Fra: owner-emc-p...@majordomo.ieee.org [mailto:owner-emc-p...@majordomo.ieee.org]På vegne av Stuart Lopata Sendt: 30. oktober 2001 16:07 Til: emc Emne: EN 55022 limits The radiated limits are stated for 10 meters but our measurements are at 3 meters. Is it ok to use 3 meter data and what should the new limits be (may be 10 dB higher)? Thanks, Stuart Lopata --- 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: No longer online until our new server is brought online and the old messages are imported into the new server. --- 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: No longer online until our new server is brought online and the old messages are imported into the new server.
Re: one more thing about duty cycle...
I have no idea what the reference is but please recall that I demonstrated two items: AVERAGE DETECTION is numerically computed by derating peak detected signal by 10 log (duty cycle) (assumes time constants are long wrt to IF filter time constant). PULSE DESENSITIZATION (or broadband correction) is calculated as 20 log (duty cycle) added to peak detected signal (working in log space). This assumes that duty cycle of detected signal is short relative to IF filter time constant. In order for this to have any validity, a victim receiver must exist which has a wider IF bandwidth than the test receiver which made the measurement. -- >From: "Stuart Lopata" >To: "emc" >Subject: one more thing about duty cycle... >Date: Tue, Oct 30, 2001, 9:27 AM > > > I found the reference that used 20log() for the correction factors. > > TCB Training > Unlicensed Devices > Part I > Richard Fabina > > This was given to us by the FCC for training our TCB people and part of a > TCB training course at NIST. > > I agree that the correction factor should be 10log(), but would like to see > a confirmation from the actual certifiers. > So who is the final authority? > > Sincerely, > > Stuart Lopata > > > > > --- > 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: > No longer online until our new server is brought online and the old > messages are imported into the new server. > --- 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: No longer online until our new server is brought online and the old messages are imported into the new server.
RE: one more thing about duty cycle... Dimensional Analysis .. but 11 fingers makes it tricky
Now that the dust on this one has settled - my trick is to start from first principles with a spot of dimensional analysis. A ratio is dimensionless - therefore it is straight decibels and 10log. No convention - that is the definition. One of the few exceptions are Power. Power = k x V^2 Log(10) Power = K + 2 x log(10)V dB = 10xLog (10) Power = 10(K) + 20Log(10)V But then I'm only a product safety engineer, so I'll leave the follow-on question to you EMC types... Silly question though - what would be the equation have been if we had 11 fingers? :^ ] Gregg Eurolink Ltd. -One Link-199 Countries P.O. Box 310 Reedville, Virginia 22539 Phone: (804) 453-3141 Fax: (804) 453-9039 Web:www.eu-link.com --- 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: No longer online until our new server is brought online and the old messages are imported into the new server.
Re: EN 55022 limits
The limits scale linearly upward just as you say but you have to be careful with large test items because their radiation pattern does not behave the same. As long as the largest dimension of the EUT is small wrt 3 m, you should have no problems. -- >From: "Stuart Lopata" >To: "emc" >Subject: EN 55022 limits >Date: Tue, Oct 30, 2001, 9:06 AM > > > The radiated limits are stated for 10 meters but our measurements are at 3 > meters. Is it ok to use 3 meter data and what should the new limits be (may > be 10 dB higher)? > > Thanks, > > Stuart Lopata > > > > --- > 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: > No longer online until our new server is brought online and the old > messages are imported into the new server. > --- 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: No longer online until our new server is brought online and the old messages are imported into the new server.
RE: Definition for Safety Critical Component
A safety critical component is a component were the failure during normal use, forseeable misuse and fault conditions is likely to result in a hazardous condition for the operator and/or service person (includes maintenance). Richard Woods Sensormatic Electronics -Original Message- From: lcr...@tuvam.com [mailto:lcr...@tuvam.com] Sent: Tuesday, October 30, 2001 12:27 PM To: emc-p...@majordomo.ieee.org Subject: Definition for Safety Critical Component All, Does anyone have a concise definition of Safety Critical Component? I understand that the definition of this term is highly dependent on context, so let me frame it a bit I am interested in the components that may be in "high-tech" industrial equipment such as those used in the semiconductor manufacturing industry. And as for "regulatory space" I am considering the typical application of electrical design standards such as EN 60204, NFPA 79, ULK 508, EN 61010 as well as similar standards that may address the design of pneumatic, mechanical and process chemical delivery systems. I am also considering three potential populations. Operators - who interact with the tool only to get it to perform its intended function (this group can also include 'passers by' Maintenance personnel - who work with the tool to perform prescribed, well document procedures intended to keep the tool in good working order. Service personnel - who do anything necessary to get a broken tool back into operating condition. Thanks for any ideas. -Lauren Crane TUV America / TUV Product Service
Definition for Safety Critical Component
All, Does anyone have a concise definition of Safety Critical Component? I understand that the definition of this term is highly dependent on context, so let me frame it a bit I am interested in the components that may be in "high-tech" industrial equipment such as those used in the semiconductor manufacturing industry. And as for "regulatory space" I am considering the typical application of electrical design standards such as EN 60204, NFPA 79, ULK 508, EN 61010 as well as similar standards that may address the design of pneumatic, mechanical and process chemical delivery systems. I am also considering three potential populations. Operators - who interact with the tool only to get it to perform its intended function (this group can also include 'passers by' Maintenance personnel - who work with the tool to perform prescribed, well document procedures intended to keep the tool in good working order. Service personnel - who do anything necessary to get a broken tool back into operating condition. Thanks for any ideas. -Lauren Crane TUV America / TUV Product Service
Re: Low Frequency Conducted Immunity....
I'd be inclined to look at the design. Bandaids have a way of multiplying until your product looks like a mummy. If it's a low-level power problem, make sure the EUT's regulator can respond to induced ripple. This may be as simple as exchanging a cheap electrolytic cap for one with better ESR, or you may have to redesign the regulator's filter loop. If the problem is unregulated power to a PA stage, try getting better balance in the stage; look at it as a CMR problem. Look for ground-loop problems; a shared return between a stage run from the injection point and a low-level amplifier will do what you report. And you might look for an unintended path. Active switches can be modulated, too. Good luck! Cortland --- 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: No longer online until our new server is brought online and the old messages are imported into the new server.
one more thing about duty cycle...
I found the reference that used 20log() for the correction factors. TCB Training Unlicensed Devices Part I Richard Fabina This was given to us by the FCC for training our TCB people and part of a TCB training course at NIST. I agree that the correction factor should be 10log(), but would like to see a confirmation from the actual certifiers. So who is the final authority? Sincerely, Stuart Lopata --- 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: No longer online until our new server is brought online and the old messages are imported into the new server.
EN 55022 limits
The radiated limits are stated for 10 meters but our measurements are at 3 meters. Is it ok to use 3 meter data and what should the new limits be (may be 10 dB higher)? Thanks, Stuart Lopata --- 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: No longer online until our new server is brought online and the old messages are imported into the new server.
October, 2001 EMC/Telco/Product Safety Update Now Available
The Curtis-Straus Update is for October, 2001 is now available at: http://www.conformity-update.com The headlines are: FCC Proposes Changes To Part 15. Commission Adopts SDR Rules. FCC Expands Exploration Of Options For 3G Wireless. Standards Development Participants May Be Subject To Disclosure. Efforts To Defraud FDA Land Executive In Jail. CPSC Actions In The News. Commission Revises Eco-Label Criteria For PCs, Laptops. Here's Our European Conformity Assessment Contact List. Agilent Software Upgrade For EN 61000-3-2 Amendment A14 Available. New Electromagnetic Cannon Fires Pain, Not Shells. EM Radiation Proof Clothes? Meetings and Seminars. --- 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: No longer online until our new server is brought online and the old messages are imported into the new server.
Re: Keep off the grass: RF emissions!
I read in !emc-pstc that Lothar Schmidt wrote (in <5EFB06767D7DD211828C0008C74CE95B414D40@CALVIN>) about 'Keep off the grass: RF emissions!', on Mon, 29 Oct 2001: >I guess the EN 55014-1,2 would be more applicable regarding EMC in Europe. They are written very largely around products that have at least a mains lead and often other external cables. I suppose the robot lawn-mower does not have external cables. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Eat mink and be dreary! --- 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: No longer online until our new server is brought online and the old messages are imported into the new server.
FW: FDA & FCC
Jim, I agree with you that Sec 18.101 would appear to exclude ultrasound equipment from the scope of Part 18. Nevertheless medical ultrasound equipment is specifically mentioned in Sec 18.107(f) and Sec 18.121. This discussion is rather academic in that Sec 18.121 excludes "non-consumer ultrasound equipment...that is used for medical diagnostic and monitoring applications..." from most of the requirements of Part 18. So I think that the situation is that formally ultrasound equipment is subject to Part 18, but it is exempted from most of the requirements. In answer to your last question. Ultrasound equipment does not have to be certified to Part 18, but the FCC does consider this equipment to be in the 'domain' of Part 18, and can, for instance, demand to inspect the equipment (under Sec 18.113). Best Regards, Jon Griver http://www.601help.com - The Medical Device Developers' Guide to IEC 60601-1 > Jon, > > If you look at Sec. 18.101 Basis and purpose, part 18 only applies to > "medical equipment that emits > electromagnetic energy on frequencies within the radio frequency > spectrum in order to prevent harmful interference to authorized radio > communication services." The Ultrasound equipment that I am familiar with > does not emit electromagnetic energy that would cause interference. They > also comply with CISPR 11 class A or B emissions requirements depending on > where they are used. Do you certify your Ultrasound equipment to Part 18? > > Best regards, > > Jim > > -Original Message- > From: owner-emc-p...@majordomo.ieee.org > [mailto:owner-emc-p...@majordomo.ieee.org]On Behalf Of Jon Griver > Sent: Monday, October 29, 2001 8:20 AM > To: emc-p...@majordomo.ieee.org > Subject: FW: FDA & FCC > > > Jim, > > Yes and no. > > Yes. Medical ultrasound equipment is explicitly included in the scope of > Part 18 under Section 18.107(f). I assume the logic is that RF > circuits are > required to generate the ultrasound. > > No. Section 18.121 excludes non-consumer medical ultrasound equipment, > except for a few sections of Part 18 that deal mainly with allowed > frequencies. > > Best Regards, > > Jon Griver > http://www.601help.com - The Medical Device Developers' Guide to > IEC 60601-1 > > > > > > Jon, Ultrasound equipment does us use RF directly to treat or diagnose > > patients. I don't believe Ultrasound equipment falls under part 18. > > > > The FDA is now recommending the use of IEC 60601-1-2; 2001 for EMC. > > > > Best regards, > > > > Jim > > > > -Original Message- > > From: owner-emc-p...@majordomo.ieee.org > > [mailto:owner-emc-p...@majordomo.ieee.org]On Behalf Of Jon Griver > > Sent: Sunday, October 28, 2001 2:07 AM > > To: emc-p...@majordomo.ieee.org > > Subject: FDA & FCC > > > > > > This is not quite the whole story. > > > > Medical devices must get FDA approval, including EMC aspects. However, > > medical equipment is also subject to FCC regulations. > > > > FCC Part 15 exempts medical equipment (Sec 15.103), though it is still > > subject to the general requirements of the FCC in that devices found to > > cause interference can be stopped from operating. > > > > Medical devices that intentionally use EM radiation are subject > > to FCC Part > > 18. This includes ultrasound equipment, diathermy equipment, microwave > > therapeutic devices. > > > > Regards, > > > > Jon Griver > > http://www.601help.com - The Medical Device Developers' Guide to > > IEC 60601-1 > > > > > > > > > > > > Hi, > > > > > > In the USA, it is the FDA. For most medical products, the FDA > > determines > > > that your product is Substantially Equivalent to a legally > > > marketed device. > > > This is the FDA 510(k) process. They issue you a letter that > > > allows you to > > > legally market the device. > > > > > > For EMC, the FDA usually wants to see that you comply with IEC > > > 60601-1-2. > > > > > > Ned > > > > > > > > > Ned Devine > > > Program Manager III > > > Entela, Inc. > > > 3033 Madison Ave. SE > > > Grand Rapids, MI 49548 > > > > > > 616 248 9671 Phone > > > 616 574 9752 Fax > > > ndev...@entela.com e-mail > > > > > > > > > > > > > > > > > > -Original Message- > > > From: am...@westin-emission.no [mailto:am...@westin-emission.no] > > > Sent: Friday, October 26, 2001 5:15 AM > > > To: emc-p...@majordomo.ieee.org > > > Subject: FDA > > > > > > > > > > > > Hi all, > > > > > > What is the basic differences between FDA and FCC ? Don't laugh, > > > yes I know > > > it is a silly question, but if you want to certify medical > > equipment, are > > > the requirements covered in the FDA or in the FCC regulations ? > > > > > > As you understand, within this field, I'm a really novice ... > > > > > > Best regards > > > Amund Westin, Oslo/Norway > > > > > > > > > > > > --- > > > This message is from the IEEE EMC Society Product Safety > > > Technical Committee emc-pstc discussion list. > > > > > > Visit our web site at: http://ww
Re: skinny power cords.
My apologies to Andrew Carson! Somehow I scrolled down so that only the Cc: for ron_wellman was visible and, therefore, typed in the wrong salutation. This would not happen were we writing letters in long hand; however, we would also not be addressing so many people at the same time. I am impressed that it takes a guy from England to tell us folks here the chapter and verse where to find things in our own electrical code. Let's hear more of such from over the pond! taniagr...@msn.com - Original Message - From: Tania Grant Sent: Monday, October 29, 2001 7:39 PM To: acar...@uk.xyratex.com Cc: WELLMAN,RON (A-PaloAlto,ex1); emc Subject: Re: skinny power cords. Ron, Thank you. I appreciate the reference to the NEC! taniagr...@msn.com - Original Message - From: acar...@uk.xyratex.com Sent: Monday, October 29, 2001 4:09 AM To: Tania Grant Cc: WELLMAN,RON (A-PaloAlto,ex1); emc Subject: Re: skinny power cords. Tania The V in SVT does indeed stand for Vacuum and not Vinyl. In reference to the Trade name of this type of cable being Vacuum cleaner cord not suitable for hard usage. Article 400 of the NEC, page 70-211 to 70-224 ( in the 1999 edition) defines all the US cordage definitions. What the letters mean and what use the cordage is suitable for. Tania Grant wrote: Ron, I am a bit confused;-- you stated " SVT is for vacuum cleaners, not consumer products."Is not a vacuum cleaner a consumer product??? I may be wrong, but I thought that the "V" in the SVT designation stands for "vinyl", a soft and flexible insulation. Since many vacuum cleaning cords are automatically wound inside the appliance, that suits the application quite well. SJT cords, on the other hand, are more stiff; however, they are also used with consumer products. Perhaps someone else can shed more specific light on the various U.S. power cord applications and their respective nomenclature. I know that in the SJTO designation, the "O" stands for resistance to Oil, and that such cords are recommended (required?) in industrial areas where oil would likely be present, such as in car garages, etc. Tania granttaniagr...@msn.com - Original Message - From: WELLMAN,RON (A-PaloAlto,ex1) Sent: Sunday, October 28, 2001 6:50 AM To: emc Subject: RE: skinny power cords. In North America we rate cordage according to usage. The probability of crushing a cord is dependent on its usage and the selection of the cordage type by the manufacturer. I have seen many IT manufacturers use SVT cordage in North America. In my opinion SVT cordage is chosen instead of SJT just to save money. SVT is for vacuum cleaners, not consumer products. So, would fusing a plug in the USA/Canada be needed? I say no because we have a working system to rate cordage according to usage. If people choose to abuse the system, they assume the risk and liability for doing so. Regards, +=+ |Ronald R. Wellman|Voice : 408-345-8229 | |Agilent Technologies |FAX : 408-553-2412 | |5301 Stevens Creek Blvd.,|E-Mail: ron_well...@agilent.com| |Mailstop 54L-BB |WWW : http://www.agilent.com | |Santa Clara, California 95052 USA| | +=+ | "Common sense is the collection of prejudices acquired by age | | eighteen." - Albert Einstein | +=+ -Original Message- From: Nick Rouse [mailto:100626.3...@compuserve.com] Sent: Friday, October 26, 2001 2:11 PM To: emc Subject: Fw: skinny power cords. - Original Message - From: "Nick Rouse" <100626.3...@compuserve.com> To: "WELLMAN,RON (A-PaloAlto,ex1)" Sent: Friday, October 26, 2001 9:52 PM Subject: Re: skinny power cords. > Earlier on in the thread it was not about arcing across the pins of a plug > but about the dangers or having a power cord rated lower than the > protection in the supply. Damage to the cord such as squashing it under > the legs of furniture or repeated flexing or overloads in simple unfused > equipment like table lights can cause overheating in the cord that will not > trip out the circuit protection. > Fused plugs do allow thin power cords to be used safely from supplies that > have a high rated current, In the UK power outlets are on a ring protected > by a 30A or 50A fuse or breaker. > > Nick Rouse > > Original Message - > From: "WELLMAN,RON (A-PaloAlto,ex1)" > To: > Sent: Friday, October 26, 2001 3:05 PM > Subject: RE: skinny power cords. > > > > > > > > Hello all, > > > > Earlier on in this thread it was eluded that this problem was leading to > the > > need of fus
Re: skinny power cords.
Ron, Thank you. I appreciate the reference to the NEC! taniagr...@msn.com - Original Message - From: acar...@uk.xyratex.com Sent: Monday, October 29, 2001 4:09 AM To: Tania Grant Cc: WELLMAN,RON (A-PaloAlto,ex1); emc Subject: Re: skinny power cords. Tania The V in SVT does indeed stand for Vacuum and not Vinyl. In reference to the Trade name of this type of cable being Vacuum cleaner cord not suitable for hard usage. Article 400 of the NEC, page 70-211 to 70-224 ( in the 1999 edition) defines all the US cordage definitions. What the letters mean and what use the cordage is suitable for. Tania Grant wrote: Ron, I am a bit confused;-- you stated " SVT is for vacuum cleaners, not consumer products."Is not a vacuum cleaner a consumer product??? I may be wrong, but I thought that the "V" in the SVT designation stands for "vinyl", a soft and flexible insulation. Since many vacuum cleaning cords are automatically wound inside the appliance, that suits the application quite well. SJT cords, on the other hand, are more stiff; however, they are also used with consumer products. Perhaps someone else can shed more specific light on the various U.S. power cord applications and their respective nomenclature. I know that in the SJTO designation, the "O" stands for resistance to Oil, and that such cords are recommended (required?) in industrial areas where oil would likely be present, such as in car garages, etc. Tania granttaniagr...@msn.com - Original Message - From: WELLMAN,RON (A-PaloAlto,ex1) Sent: Sunday, October 28, 2001 6:50 AM To: emc Subject: RE: skinny power cords. In North America we rate cordage according to usage. The probability of crushing a cord is dependent on its usage and the selection of the cordage type by the manufacturer. I have seen many IT manufacturers use SVT cordage in North America. In my opinion SVT cordage is chosen instead of SJT just to save money. SVT is for vacuum cleaners, not consumer products. So, would fusing a plug in the USA/Canada be needed? I say no because we have a working system to rate cordage according to usage. If people choose to abuse the system, they assume the risk and liability for doing so. Regards, +=+ |Ronald R. Wellman|Voice : 408-345-8229 | |Agilent Technologies |FAX : 408-553-2412 | |5301 Stevens Creek Blvd.,|E-Mail: ron_well...@agilent.com| |Mailstop 54L-BB |WWW : http://www.agilent.com | |Santa Clara, California 95052 USA| | +=+ | "Common sense is the collection of prejudices acquired by age | | eighteen." - Albert Einstein | +=+ -Original Message- From: Nick Rouse [mailto:100626.3...@compuserve.com] Sent: Friday, October 26, 2001 2:11 PM To: emc Subject: Fw: skinny power cords. - Original Message - From: "Nick Rouse" <100626.3...@compuserve.com> To: "WELLMAN,RON (A-PaloAlto,ex1)" Sent: Friday, October 26, 2001 9:52 PM Subject: Re: skinny power cords. > Earlier on in the thread it was not about arcing across the pins of a plug > but about the dangers or having a power cord rated lower than the > protection in the supply. Damage to the cord such as squashing it under > the legs of furniture or repeated flexing or overloads in simple unfused > equipment like table lights can cause overheating in the cord that will not > trip out the circuit protection. > Fused plugs do allow thin power cords to be used safely from supplies that > have a high rated current, In the UK power outlets are on a ring protected > by a 30A or 50A fuse or breaker. > > Nick Rouse > > Original Message - > From: "WELLMAN,RON (A-PaloAlto,ex1)" > To: > Sent: Friday, October 26, 2001 3:05 PM > Subject: RE: skinny power cords. > > > > > > > > Hello all, > > > > Earlier on in this thread it was eluded that this problem was leading to > the > > need of fused power plugs, similar to what is done in the UK. However, > based > > on the analyses of several people, I do not see how a fused plug would of > > prevented the failure that Robert experienced. > > > > Regards, > > +=+ > > |Ronald R. Wellman|Voice : 408-345-8229 | > > |Agilent Technologies |FAX : 408-553-2412 | > > |5301 Stevens Creek Blvd.,|E-Mail: ron_well...@agilent.com| > > |Mailstop 54L-BB |WWW : http://www.agilent.com | > > |Santa Clara, California 95052 USA| | > > +===
RE: FDA & FCC
Jon, If you look at Sec. 18.101 Basis and purpose, part 18 only applies to "medical equipment that emits electromagnetic energy on frequencies within the radio frequency spectrum in order to prevent harmful interference to authorized radio communication services." The Ultrasound equipment that I am familiar with does not emit electromagnetic energy that would cause interference. They also comply with CISPR 11 class A or B emissions requirements depending on where they are used. Do you certify your Ultrasound equipment to Part 18? Best regards, Jim -Original Message- From: owner-emc-p...@majordomo.ieee.org [mailto:owner-emc-p...@majordomo.ieee.org]On Behalf Of Jon Griver Sent: Monday, October 29, 2001 8:20 AM To: emc-p...@majordomo.ieee.org Subject: FW: FDA & FCC Jim, Yes and no. Yes. Medical ultrasound equipment is explicitly included in the scope of Part 18 under Section 18.107(f). I assume the logic is that RF circuits are required to generate the ultrasound. No. Section 18.121 excludes non-consumer medical ultrasound equipment, except for a few sections of Part 18 that deal mainly with allowed frequencies. Best Regards, Jon Griver http://www.601help.com - The Medical Device Developers' Guide to IEC 60601-1 > > Jon, Ultrasound equipment does us use RF directly to treat or diagnose > patients. I don't believe Ultrasound equipment falls under part 18. > > The FDA is now recommending the use of IEC 60601-1-2; 2001 for EMC. > > Best regards, > > Jim > > -Original Message- > From: owner-emc-p...@majordomo.ieee.org > [mailto:owner-emc-p...@majordomo.ieee.org]On Behalf Of Jon Griver > Sent: Sunday, October 28, 2001 2:07 AM > To: emc-p...@majordomo.ieee.org > Subject: FDA & FCC > > > This is not quite the whole story. > > Medical devices must get FDA approval, including EMC aspects. However, > medical equipment is also subject to FCC regulations. > > FCC Part 15 exempts medical equipment (Sec 15.103), though it is still > subject to the general requirements of the FCC in that devices found to > cause interference can be stopped from operating. > > Medical devices that intentionally use EM radiation are subject > to FCC Part > 18. This includes ultrasound equipment, diathermy equipment, microwave > therapeutic devices. > > Regards, > > Jon Griver > http://www.601help.com - The Medical Device Developers' Guide to > IEC 60601-1 > > > > > > > Hi, > > > > In the USA, it is the FDA. For most medical products, the FDA > determines > > that your product is Substantially Equivalent to a legally > > marketed device. > > This is the FDA 510(k) process. They issue you a letter that > > allows you to > > legally market the device. > > > > For EMC, the FDA usually wants to see that you comply with IEC > > 60601-1-2. > > > > Ned > > > > > > Ned Devine > > Program Manager III > > Entela, Inc. > > 3033 Madison Ave. SE > > Grand Rapids, MI 49548 > > > > 616 248 9671 Phone > > 616 574 9752 Fax > > ndev...@entela.com e-mail > > > > > > > > > > > > -Original Message- > > From: am...@westin-emission.no [mailto:am...@westin-emission.no] > > Sent: Friday, October 26, 2001 5:15 AM > > To: emc-p...@majordomo.ieee.org > > Subject: FDA > > > > > > > > Hi all, > > > > What is the basic differences between FDA and FCC ? Don't laugh, > > yes I know > > it is a silly question, but if you want to certify medical > equipment, are > > the requirements covered in the FDA or in the FCC regulations ? > > > > As you understand, within this field, I'm a really novice ... > > > > Best regards > > Amund Westin, Oslo/Norway > > > > > > > > --- > > 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: > > No longer online until our new server is brought online and the old > > messages are imported into the new server. > > > > --- > > 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 Heald
RE: Keep off the grass: RF emissions!
John, Massimo I guess the EN 55014-1,2 would be more applicable regarding EMC in Europe. However the ETSI depending on the answers from Massimo can cover already a good part and should be seen in combination to the EN. Best Regards Lothar Schmidt Technical Manager EMC/Radio BQB CETECOM Inc. 411 Dixon Landing Road Milpitas, CA 95035 * +1 408 586 6214 * +1 408 586 6299 -Original Message- From: John Woodgate [mailto:j...@jmwa.demon.co.uk] Sent: Monday, October 29, 2001 8:39 AM To: emc-p...@majordomo.ieee.org Subject: Re: Keep off the grass: RF emissions! I read in !emc-pstc that Massimo Polignano wrote (in ) about 'Keep off the grass: RF emissions!', on Mon, 29 Oct 2001: >Is there any applicable product standard dealing with EMC and safety of >that kind of devices? In Europe, the Generic EMC Standards would apply plus whatever ETSI standards cover the radio part. For safety, I suppose EN60335-1 if the propulsion is electric. >Do you think it is to be handled as an intentional RF transmitter, >similarly to an ISM? Yes. Unless it's actually an induction system rather than an EM-wave system, in which case the answer gets less definite. What frequency does the transmitter use? >Let's consider it is not an intentional transmitter, as the emission >depends on the broadness of the reference loop, does it make sense to do >measurement at three or ten meters? You probably need to measure the magnetic field if the transmitter has a loop antenna, not the electric field, so the 3m/10m distance requirement is not relevant. But there probably needs to be a specified distance, maybe 1 m. >Do you think immunity as well can be anlysed regardless the actual >installation? Immunity is VERY important. We don't want these things running amok every time an EM disturbance occurs! -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Eat mink and be dreary! --- 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: No longer online until our new server is brought online and the old messages are imported into the new server. --- 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: No longer online until our new server is brought online and the old messages are imported into the new server.
NVLAP vs A2LA
Members, Our lab is under UKAS accreditation and actually for the last 3 years. For some reason, I would like to look into either NVLAP or A2LA as our second accreditor. I would like to know pros & cons between NVLAP & A2LA accreditation from a test lab's point of view. I know they are both signatures of ILAC and should have the same status, what I need to know are in specific: 1. Cost involved in accreditation 2. Customer may think which one is more "prestigious" 3. Process complications (assume both with ISO 17025) 4. Time frame from application to completion (assume at the same readiness level). and the last but not the least, which one you prefer to choose and why. This is NOT a survey, neither an "on-line" discussion, but the actual decision I need to make shortly. I appreciate your comments "off-line". Please be rest assured all of your valuable comments would be kept confidential. Thank you, Leslie __ Do You Yahoo!? Make a great connection at Yahoo! Personals. http://personals.yahoo.com --- 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: No longer online until our new server is brought online and the old messages are imported into the new server.
