Re: [PSES] I would like to hear your thoughts please
All the test labs I have used have a qualifier that the results are only for the specimen/s submitted. As the manufacturer, I provide the rational to include in the test report for the configuration/s submitted. For about 4 decades, a minimum and a maximum configs have sufficed. ps. If the marketing model number changes for various configs, that generally gets a some degree of testing with notes added to test report to explain the differences and commonalities, and the front page gets modified that the test report covers these additional models. On Friday, April 12, 2024, 2:59:06 PM EDT, Lauren Crane <1afd08519f18-dmarc-requ...@listserv.ieee.org> wrote: I think one could postulate a worst case hardware/software combination, but it would have to be well defended in text along the lines of “no other configuration could be worst case because…” followed by a discussion of the physical aspects of the other configurations and what they imply, based on ‘first principles’, regarding emissions and susceptibility. Even then, if there are many configurations (e.g., more than 5?), it would be wise to test a one or two for which your written hypothesis might be less certain. The EMCD guidelines (19 Dec 2018) seem to me to be accepting of this idea… - “The EMC assessment needs to take into account all normal intended operating conditions of the apparatus. In cases where the apparatus can take different configurations, the electromagnetic compatibility assessment must confirm that the apparatus meets the essential requirements, “in all possible configurations identified by the manufacturer as representative of its intended use”[quoting Annex II.2]”. - “Where apparatus can take different configurations, the EMC assessment shall confirm that the apparatus meets the essential requirements in all of the configurations foreseeable by the manufacturer as representative of normal use in intended applications.The manufacturer is responsible for identifying the possible configurations and the choice of the worst case(s). The use of the worst case approach needs to be documented in the technical documentation”[35]. [35]=” Within the immunity and emission phenomena to be covered, different worst case selections may occur (because of non-related phenomena). This may increase the number of cases to be investigated “ Note particularly - the guide highlights the obligation of deciding worst case is placed on the manufacturer. If you provide them some guidance but remind them the decision of testing fewer or more of the configurations rests with them, they may have a softer attitude towards more testing. Best regards, -Lauren Confidential – Limited Access and Use From: Bill Owsley <00f5a03f18eb-dmarc-requ...@listserv.ieee.org> Sent: Friday, April 12, 2024 1:19 PM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] I would like to hear your thoughts please | | External Email: Do NOT reply, click on links, or open attachmentsunless you recognize the sender and know the content is safe. If you believe this email may be unsafe, please click on the “Report Phishing” button on the top right of Outlook. | The usual response is that it depends... More 'light' reading ! To start ! https://www.fcc.gov/sites/default/files/32-KDB-996369-Modules-TCB_Oct_2023.pdf On Wednesday, April 10, 2024, 5:22:12 PM EDT, Lfresearch <00734758d943-dmarc-requ...@listserv.ieee.org> wrote: Sorry for the late reply, but I did feel the need to express strong disagreement with some statements here. Lets take there first one: how will you know which is worst case if you don’t test. Seriously? I would answer this by saying that an EMC engineer with any proficiency can make an educated decision as to what would be the worst case, further, if one can’t do that you shouldn’t probably be in EMC Engineering. Is the old saying from school days “ You should have an idea of the answer before doing the problem “ no longer stressed in school! The back reference to Boeing is utter BS, sorry Gert, but as someone who contracts for Boeing I take a very strong exception to that ridiculous statement. There is absolutely NO correlation between a poor quality subcontractor and the EMC performance of an EUT. It may be true for airbus, but leave my Boeing alone please. Back to the problem at hand, and serious answers only please. At what point(s) does one draw the line eliminating the need for testing similar designs. Thanks in advance, Derek Walton. On Apr 6, 2024, at 7:55 AM, Gert Gremmen F4LDP wrote: Dear All, Within the framework of the EMCD, all configurations shall be conform, so if you choose to actually test, all configurations shall be part of the test. The subject of worse case is a "miroir d'alouette"... how will you ever know
Re: [PSES] I would like to hear your thoughts please
I think one could postulate a worst case hardware/software combination, but it would have to be well defended in text along the lines of “no other configuration could be worst case because…” followed by a discussion of the physical aspects of the other configurations and what they imply, based on ‘first principles’, regarding emissions and susceptibility. Even then, if there are many configurations (e.g., more than 5?), it would be wise to test a one or two for which your written hypothesis might be less certain. The EMCD guidelines (19 Dec 2018) seem to me to be accepting of this idea… * “The EMC assessment needs to take into account all normal intended operating conditions of the apparatus. In cases where the apparatus can take different configurations, the electromagnetic compatibility assessment must confirm that the apparatus meets the essential requirements, “in all possible configurations identified by the manufacturer as representative of its intended use”[quoting Annex II.2]”. * “Where apparatus can take different configurations, the EMC assessment shall confirm that the apparatus meets the essential requirements in all of the configurations foreseeable by the manufacturer as representative of normal use in intended applications. The manufacturer is responsible for identifying the possible configurations and the choice of the worst case(s). The use of the worst case approach needs to be documented in the technical documentation”[35]. [35]=” Within the immunity and emission phenomena to be covered, different worst case selections may occur (because of non-related phenomena). This may increase the number of cases to be investigated “ Note particularly - the guide highlights the obligation of deciding worst case is placed on the manufacturer. If you provide them some guidance but remind them the decision of testing fewer or more of the configurations rests with them, they may have a softer attitude towards more testing. Best regards, -Lauren Confidential – Limited Access and Use From: Bill Owsley <00f5a03f18eb-dmarc-requ...@listserv.ieee.org> Sent: Friday, April 12, 2024 1:19 PM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] I would like to hear your thoughts please External Email: Do NOT reply, click on links, or open attachments unless you recognize the sender and know the content is safe. If you believe this email may be unsafe, please click on the “Report Phishing” button on the top right of Outlook. The usual response is that it depends... More 'light' reading ! To start ! https://www.fcc.gov/sites/default/files/32-KDB-996369-Modules-TCB_Oct_2023.pdf On Wednesday, April 10, 2024, 5:22:12 PM EDT, Lfresearch <00734758d943-dmarc-requ...@listserv.ieee.org<mailto:00734758d943-dmarc-requ...@listserv.ieee.org>> wrote: Sorry for the late reply, but I did feel the need to express strong disagreement with some statements here. Lets take there first one: how will you know which is worst case if you don’t test. Seriously? I would answer this by saying that an EMC engineer with any proficiency can make an educated decision as to what would be the worst case, further, if one can’t do that you shouldn’t probably be in EMC Engineering. Is the old saying from school days “ You should have an idea of the answer before doing the problem “ no longer stressed in school! The back reference to Boeing is utter BS, sorry Gert, but as someone who contracts for Boeing I take a very strong exception to that ridiculous statement. There is absolutely NO correlation between a poor quality subcontractor and the EMC performance of an EUT. It may be true for airbus, but leave my Boeing alone please. Back to the problem at hand, and serious answers only please. At what point(s) does one draw the line eliminating the need for testing similar designs. Thanks in advance, Derek Walton. On Apr 6, 2024, at 7:55 AM, Gert Gremmen F4LDP mailto:g.grem...@cetest.nl>> wrote: Dear All, Within the framework of the EMCD, all configurations shall be conform, so if you choose to actually test, all configurations shall be part of the test. The subject of worse case is a "miroir d'alouette"... how will you ever know which is worst case without carrying out the test ? A pre-scan is informative but the radiated emission test contains already a pre-scan (peak) for the final QP-measurement. We already require a EMC risk analysis which is a kind of pre-scan too. How many pre-pre-prescans will we need to be sure ? "to repeat some (which?) test to make sure nothing was broken" it's another discipline, but that is how Boeing lost a door in flight. And that is not a unregulated sector without thorough quality scans (understatement), and still it happens. Imagine the costs and effort for Boeing to rebuild their reputation ? Didn't we all learned the exponential graph of EMC costs versus developmen
Re: [PSES] I would like to hear your thoughts please
The usual response is that it depends... More 'light' reading ! To start ! https://www.fcc.gov/sites/default/files/32-KDB-996369-Modules-TCB_Oct_2023.pdf On Wednesday, April 10, 2024, 5:22:12 PM EDT, Lfresearch <00734758d943-dmarc-requ...@listserv.ieee.org> wrote: Sorry for the late reply, but I did feel the need to express strong disagreement with some statements here. Lets take there first one: how will you know which is worst case if you don’t test. Seriously? I would answer this by saying that an EMC engineer with any proficiency can make an educated decision as to what would be the worst case, further, if one can’t do that you shouldn’t probably be in EMC Engineering. Is the old saying from school days “ You should have an idea of the answer before doing the problem “ no longer stressed in school! The back reference to Boeing is utter BS, sorry Gert, but as someone who contracts for Boeing I take a very strong exception to that ridiculous statement. There is absolutely NO correlation between a poor quality subcontractor and the EMC performance of an EUT. It may be true for airbus, but leave my Boeing alone please. Back to the problem at hand, and serious answers only please. At what point(s) does one draw the line eliminating the need for testing similar designs. Thanks in advance, Derek Walton. On Apr 6, 2024, at 7:55 AM, Gert Gremmen F4LDP wrote: Dear All, Within the framework of the EMCD, all configurations shall be conform, so if you choose to actually test, all configurations shall be part of the test. The subject of worse case is a "miroir d'alouette"... how will you ever know which is worst case without carrying out the test ? A pre-scan is informative but the radiated emission test contains already a pre-scan (peak) for the final QP-measurement. We already require a EMC risk analysis which is a kind of pre-scan too. How many pre-pre-prescans will we need to be sure ? "to repeat some (which?) test to make sure nothing was broken" it's another discipline, but that is how Boeing lost a door in flight. And that is not a unregulated sector without thorough quality scans (understatement), and still it happens. Imagine the costs and effort for Boeing to rebuild their reputation ? Didn't we all learned the exponential graph of EMC costs versus development time ? If you need proof (for authorities, or for yourself), nothing can replace the actual test. Gert Gremmen On 6-4-2024 0:47, Lfresearch wrote: Hi folks, I would like to advise a client at where to draw the line on what needs testing. I would like to solicit opinions besides my own. Otherwise it’s the fox urging the chicken coop… So a manufacturer that makes a product of which there will be several variants. All use the same board, but have different sections of circuits populated. This may require slightly different code to run on the same uP in each case. So.. The burning question is can we perform and analysis that postulates a worse case hardware/software combination and test just one configuration? Or, do we have to do every combination? Or, are there some guidelines about where we draw the line of what to test and what can be claimed as similarity? Off list responses are welcome too. Thanks, Derek Walton LFResearch/SSCLabs. - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to EMC-PSTC@LISTSERV.IEEE.ORG All emc-pstc postings are archived and searchable on the web at: https://www.mail-archive.com/emc-pstc@listserv.ieee.org/ Website: https://ewh.ieee.org/soc/pses/ Instructions: https://ewh.ieee.org/soc/pses/list.html (including how to unsubscribe) List rules: https://ewh.ieee.org/soc/pses/listrules.html For help, send mail to the list administrators: Mike Sherman at: msherma...@comcast.net Rick Linford at: linf...@ieee.org For policy questions, send mail to: Jim Bacher: _ To unsubscribe from the EMC-PSTC list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC=1 -- Independent Expert on CE marking EMC Consultant Electrical Safety Consultant This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to EMC-PSTC@LISTSERV.IEEE.ORG All emc-pstc postings are archived and searchable on the web at: https://www.mail-archive.com/emc-pstc@listserv.ieee.org/ Website: https://ewh.ieee.org/soc/pses/ Instructions: https://ewh.ieee.org/soc/pses/list.html (including how to unsubscribe) List rules: https://ewh.ieee.org/soc/pses/listrules.html For help, send mail to the list administrators: Mike Sherman at: msherma...@comcast.net Rick Linford at: linf...@ieee.org For policy questions, send mail to: Jim Bacher at: j.bac...@ieee.org To
Re: [PSES] I would like to hear your thoughts please
Sorry for the late reply, but I did feel the need to express strong disagreement with some statements here.Lets take there first one: how will you know which is worst case if you don’t test. Seriously? I would answer this by saying that an EMC engineer with any proficiency can make an educated decision as to what would be the worst case, further, if one can’t do that you shouldn’t probably be in EMC Engineering. Is the old saying from school days “ You should have an idea of the answer before doing the problem “ no longer stressed in school!The back reference to Boeing is utter BS, sorry Gert, but as someone who contracts for Boeing I take a very strong exception to that ridiculous statement. There is absolutely NO correlation between a poor quality subcontractor and the EMC performance of an EUT. It may be true for airbus, but leave my Boeing alone please.Back to the problem at hand, and serious answers only please.At what point(s) does one draw the line eliminating the need for testing similar designs.Thanks in advance,Derek Walton.On Apr 6, 2024, at 7:55 AM, Gert Gremmen F4LDP wrote: Dear All, Within the framework of the EMCD, all configurations shall be conform, so if you choose to actually test, all configurations shall be part of the test. The subject of worse case is a "miroir d'alouette"... how will you ever know which is worst case without carrying out the test ? A pre-scan is informative but the radiated emission test contains already a pre-scan (peak) for the final QP-measurement. We already require a EMC risk analysis which is a kind of pre-scan too. How many pre-pre-prescans will we need to be sure ? "to repeat some (which?) test to make sure nothing was broken" it's another discipline, but that is how Boeing lost a door in flight. And that is not a unregulated sector without thorough quality scans (understatement), and still it happens. Imagine the costs and effort for Boeing to rebuild their reputation ? Didn't we all learned the exponential graph of EMC costs versus development time ? If you need proof (for authorities, or for yourself), nothing can replace the actual test. Gert Gremmen On 6-4-2024 0:47, Lfresearch wrote: Hi folks, I would like to advise a client at where to draw the line on what needs testing. I would like to solicit opinions besides my own. Otherwise it’s the fox urging the chicken coop… So a manufacturer that makes a product of which there will be several variants. All use the same board, but have different sections of circuits populated. This may require slightly different code to run on the same uP in each case. So.. The burning question is can we perform and analysis that postulates a worse case hardware/software combination and test just one configuration? Or, do we have to do every combination? Or, are there some guidelines about where we draw the line of what to test and what can be claimed as similarity? Off list responses are welcome too. Thanks, Derek Walton LFResearch/SSCLabs. - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to EMC-PSTC@LISTSERV.IEEE.ORG All emc-pstc postings are archived and searchable on the web at: https://www.mail-archive.com/emc-pstc@listserv.ieee.org/ Website: https://ewh.ieee.org/soc/pses/ Instructions: https://ewh.ieee.org/soc/pses/list.html (including how to unsubscribe) List rules: https://ewh.ieee.org/soc/pses/listrules.html For help, send mail to the list administrators: Mike Sherman at: msherma...@comcast.net Rick Linford at: linf...@ieee.org For policy questions, send mail to: Jim Bacher: _ To unsubscribe from the EMC-PSTC list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC=1 -- Independent Expert on CE marking EMC Consultant Electrical Safety Consultant This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to EMC-PSTC@LISTSERV.IEEE.ORG All emc-pstc postings are archived and searchable on the web at: https://www.mail-archive.com/emc-pstc@listserv.ieee.org/ Website: https://ewh.ieee.org/soc/pses/ Instructions: https://ewh.ieee.org/soc/pses/list.html (including how to unsubscribe) List rules: https://ewh.ieee.org/soc/pses/listrules.html For help, send mail to the list administrators: Mike Sherman at: msherma...@comcast.net Rick Linford at: linf...@ieee.org For policy questions, send mail to: Jim Bacher at: j.bac...@ieee.org To unsubscribe from the EMC-PSTC list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC=1 BEGIN:VCARD FN:Gert Gremmen N:Gremmen;Gert;;; ADR:;;1261 Route de
Re: [PSES] I would like to hear your thoughts please
I once tried to do a “worst case” analysis and decided that worst would be testing the HDMI output on the product we had designed at the highest resolution = highest frequency = biggest problem. I ran all our pre-compliance work at this frequency and neglected to check any other resolutions. When we came close to lab time, prompted by my then manager, I checked other lower frequency, lower risk (surely?) resolutions and found that the second highest frequency was exciting an unintentional resonance in the product and the emissions were 6dB higher (just over the limit). However, in our experience of testing a lot of different products, 9 times out of 10 it is the more complex configuration that is more likely to have the problems, mostly because this has a bigger surface area for risk due to the variety of circuits. I like that phrase that “EMC is all about what isn’t on the schematics” i.e. the unintended performance. You really don’t know until you test. I would agree with the other voices on here to use pre-compliance testing to establish the actual worst case if in any doubt. All the best James James Pawson Managing Director & EMC Problem Solver Unit 3 Compliance Ltd EMC : Environmental & Vibration : Electrical Safety : CE & UKCA : Consultancy <http://www.unit3compliance.co.uk/> www.unit3compliance.co.uk | <mailto:ja...@unit3compliance.co.uk> ja...@unit3compliance.co.uk +44(0)1274 911747 | +44(0)7811 139957 2 Wellington Business Park, New Lane, Bradford, BD4 8AL Registered in England and Wales # 10574298 Office hours: Every morning my full attention is on consultancy, testing, and troubleshooting activities for our customers’ projects. I’m available/contactable between 1300h to 1730h Mon/Tue/Thurs/Fri. For inquiries, bookings, and testing updates please send us an email on he...@unit3compliance.co.uk <mailto:he...@unit3compliance.co.uk> or call 01274 911747. Our lead times for testing and consultancy are typically 4-5 weeks. From: Gert Gremmen F4LDP Sent: Saturday, April 6, 2024 3:55 PM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] I would like to hear your thoughts please Dear All, Within the framework of the EMCD, all configurations shall be conform, so if you choose to actually test, all configurations shall be part of the test. The subject of worse case is a "miroir d'alouette"... how will you ever know which is worst case without carrying out the test ? A pre-scan is informative but the radiated emission test contains already a pre-scan (peak) for the final QP-measurement. We already require a EMC risk analysis which is a kind of pre-scan too. How many pre-pre-prescans will we need to be sure ? "to repeat some (which?) test to make sure nothing was broken" it's another discipline, but that is how Boeing lost a door in flight. And that is not a unregulated sector without thorough quality scans (understatement), and still it happens. Imagine the costs and effort for Boeing to rebuild their reputation ? Didn't we all learned the exponential graph of EMC costs versus development time ? If you need proof (for authorities, or for yourself), nothing can replace the actual test. Gert Gremmen On 6-4-2024 0:47, Lfresearch wrote: Hi folks, I would like to advise a client at where to draw the line on what needs testing. I would like to solicit opinions besides my own. Otherwise it’s the fox urging the chicken coop… So a manufacturer that makes a product of which there will be several variants. All use the same board, but have different sections of circuits populated. This may require slightly different code to run on the same uP in each case. So.. The burning question is can we perform and analysis that postulates a worse case hardware/software combination and test just one configuration? Or, do we have to do every combination? Or, are there some guidelines about where we draw the line of what to test and what can be claimed as similarity? Off list responses are welcome too. Thanks, Derek Walton LFResearch/SSCLabs. - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to EMC-PSTC@LISTSERV.IEEE.ORG <mailto:EMC-PSTC@LISTSERV.IEEE.ORG> All emc-pstc postings are archived and searchable on the web at: https://www.mail-archive.com/emc-pstc@listserv.ieee.org/ Website: https://ewh.ieee.org/soc/pses/ Instructions: https://ewh.ieee.org/soc/pses/list.html (including how to unsubscribe) List rules: https://ewh.ieee.org/soc/pses/listrules.html For help, send mail to the list administrators: Mike Sherman at: msherma...@comcast.net <mailto:msherma...@comcast.net> Rick Linford at: linf...@ieee.org <mailto:linf...@ieee.org> For pol
Re: [PSES] I would like to hear your thoughts please
we had a pre-compliance chamber, well correlated to compliance labs. so our inside pre-compliance testing is easy. a bit of capital to get there. We make quick scan on about every variation to get idea of the worst. Then the rest of our attention is on the version. Our goal is not detectable, but running in the double KW range, we often find some higher freq emissions. At least a 6 dB margin, preferably more, undetectable is goal. Once Japan called us on a violation around 5.8 GHz. They used peak hold over time. We could not believe it, but yes peak hold overnight in a reverb chamber found the emissions. QP and average were near zero, except we knew what we were looking for. Turns out the Japan authorities, or their contractors, did not know how to run the instruments nor what the standards required. And so were a bit difficult to deal with. After a few months of back and forth, a comment came back that after new testing, there is no concern. Mexico was much easier ! Except that all their hires were fresh out of school, so it seemed. A couple of months to coach them, and everything aligned ! ps. these are old stories, but get refreshed from the to time with new occurrences. On Sunday, April 7, 2024 at 03:57:50 PM EDT, David Schaefer <12867effceb4-dmarc-requ...@listserv.ieee.org> wrote: For EMC if the concern is emissions it would be easy to do some quick scans – 10 minutes on a peak run for each model would give you data to compare against each other to see how much the emissions profile changes due to the modifications. Immunity would take longer but the manufacturer should be able to do an engineering analysis and see what might make sense/ For radios it is significantly different. Certification of a product for FCC only applies to the product in the report and identical models as defined in 2.908. Any modifications require evaluation. Thanks, | | | | | | | | | | | | | | David Schaefer | | | | | | | Technical Manager | | | | | Element Materials Technology | | | | | 9349 W Broadway Ave | | | | | Brooklyn Park | | | , | | | | MN | | | | 55445 | | | , | | | United States | | | | | | | | | O +1 612 638 5136 | | | | ext. 10461 | | | | | david.schae...@element.com | | | | www.element.com | | | | | | | | | | | | | | | | | | | | From: John Woodgate [mailto:j...@woodjohn.uk] Sent: Saturday, April 6, 2024 3:00 AM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] I would like to hear your thoughts please CAUTION:This email originated from outside of Element Materials Technology. DO NOT click links or open attachments unless you recognize the sender and know the content is safe. Please contact the TOC if you are in any doubt about this email. I agree: pre-scan is the way to go. Document all of the steps so that you can produce your reasons for your decision if challenged. On 2024-04-06 00:05, Brent DeWitt wrote: Tough one! The problem lies in the determination of "worst case". While it would be easy to presume that having all of the hardware populated is worst case, it overlooks the effects of un-terminated stubs and other SI related issues. In addition, with the world of firmware based PLL clocks and memory traffic, it is a tough thing to determine. My opinion would be to preform the simplest pre-scan on each configuration and base the final, rigorous certification based on that knowledge. Brent Dewitt Milford, MA On 4/5/2024 6:47 PM, Lfresearch wrote: Hi folks, I would like to advise a client at where to draw the line on what needs testing. I would like to solicit opinions besides my own. Otherwise it’s the fox urging the chicken coop… So a manufacturer that makes a product of which there will be several variants. All use the same board, but have different sections of circuits populated. This may require slightly different code to run on the same uP in each case. So.. The burning question is can we perform and analysis that postulates a worse case hardware/software combination and test just one configuration? Or, do we have to do every combination? Or, are there some guidelines about where we draw the line of what to test and what can be claimed as similarity? Off list responses are welcome too. Thanks, Derek Walton LFResearch/SSCLabs. - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail toemc-p...@listserv.ieee.org All emc-pstc postings are archived and searchable on the web at: https://www.mail-archive.com/emc-pstc@listserv.ieee.org/ Website: https://ewh.ieee.org/soc/pses/ Instructions: https://ewh.ieee.org/soc/pses/list.html (including how to unsubscribe) List rules: https://ewh.ieee.org/soc/pse
Re: [PSES] I would like to hear your thoughts please
For EMC if the concern is emissions it would be easy to do some quick scans – 10 minutes on a peak run for each model would give you data to compare against each other to see how much the emissions profile changes due to the modifications. Immunity would take longer but the manufacturer should be able to do an engineering analysis and see what might make sense/ For radios it is significantly different. Certification of a product for FCC only applies to the product in the report and identical models as defined in 2.908. Any modifications require evaluation. Thanks, [cid:image503832.jpg@B3A1BD25.EF509806] David Schaefer Technical Manager Element Materials Technology 9349 W Broadway Ave Brooklyn Park , MN 55445 , United States O +1 612 638 5136 ext. 10461 david.schae...@element.com<mailto:david.schae...@element.com> www.element.com<https://us.content.exclaimer.net/?url=https%3A%2F%2Fwww.element.com%2F=ixvYNdAGEeqbBQANOhMLNA=aabe0990b90beb1196f5000d3a130b34=cZ5egsqVcuTJwdSIK2EbV6p7Tgro9jT7_Tkg-Fb3YiB23cBOgCoUmOEqeUjNn3Wb1utJh_tCAps2nMvNa74FEJYf-WrOczTU6zFlHw54Kkx7YpXyoM-CTV1wYsG6Kp67xdorBRMa5LiebYSyV1KLNeSLvlAMyCdpGXdRt4PdyKih9tRDbM50s0p_22b_gp9LGtkISjiEDnV76ZvXKmVbUxVVd0tqHec9MBwk_T418oc5ZZWOclsIYRqkwfQqf0Wqj5isA4xlnhmt49FZz-5XoxKuiGArsymw_Y4qtO9TEOwjITToveVj6b1_ZkHWiMlIWuUr1cjhpNrAxmzAv6LY8g=1=eb2a865d-4e9b-467f-aafa-354533b06f38> [cid:image331521.png@1036802E.8DDE4FC3]<https://us.content.exclaimer.net/?url=https%3A%2F%2Ftwitter.com%2FElementTesting%2F=ixvYNdAGEeqbBQANOhMLNA=aabe0990b90beb1196f5000d3a130b34=ACovrZvJeYWsDyyKT0zvYAsZsidrWJylGQABf2bJhKNtCg10KfO2BYNiEUfocR4zw1YzoxFMvQi8ibysZnq3cNZQ2enJrElHRFhuRkcKd45P1AH6s8ee-4IsaM0qk_DybvwO5i12-_P_XaBFh2_9xOmCWZdsBiX-t_6d3mt1nvVR8gKtz-8s3FLwTT0uFlbk4MqGLEBOJRREfG_ZRdBPMRb4PKgkhNDQ4QWsEBPZxwChBoMJQyoQTTD6h1cgGbuyr7tQO6Qs9Y36o1lT7tgQY1FpJ7t8IzelvDE7pnzJ7HW6Izwq6FoBil54k2vQh9lhHva6dgfz_zh9TdhlHUeFOw=1=eb2a865d-4e9b-467f-aafa-354533b06f38> [cid:image131821.png@E1E2F21A.B7D288C3]<https://us.content.exclaimer.net/?url=https%3A%2F%2Fwww.instagram.com%2Felementtesting%2F=ixvYNdAGEeqbBQANOhMLNA=aabe0990b90beb1196f5000d3a130b34=JFA_C5bAd9pBZiZaSwZX__vhNs-S3M7YTVfi09pIXK1gAXP45i_59EBt5lobzjQ9vJpXmcA6Culn3ScJ4KoeJDH_KArSoBjG1D9DgSV9uBjiqtoY_R0pRy2C2xdzJJzE23qcW1VbyOPH5oED5R5Lw4293PVxGh8b8iVg5ucDVDD7Wv1qQ397usbAsSnLgtNiNRdYaUcd117IEi8S1tvs_yBmd5EfMYwWk3mRXndcszbDP4fNvqHXqAjwMjzPWfEiCBLm5q16NTaxc6zYjxG7fKDkoKqsDx9IceOzpt4VP1AaVUISQ4pP01qjUK926Mb3n4aIBXlPNdNFtQdU02BIgw=1=eb2a865d-4e9b-467f-aafa-354533b06f38> [cid:image386740.png@C45961D1.A9A92D34]<https://us.content.exclaimer.net/?url=https%3A%2F%2Fwww.youtube.com%2Fc%2FElementTesting=ixvYNdAGEeqbBQANOhMLNA=aabe0990b90beb1196f5000d3a130b34=qgxe1vvCl-XANIN26LoMZ_puPisQ0Ly4xaIIvKvXNru81qXWfAY10HToiRKguS1vq7Oe9AiAIdiBZcovvx21mZntAAB0D8YKytpGwpv6HOVPlgZoIbzqF7yEdQ6V0cAOwsOVs3J5x0c5gfmvTx4E8aLO9TvJhoWWIQh82YXZ6vCKjz-It2yKE-XH6SqslPD6z-iSnTs-HuXk_gJtocOYc_yM6WKneytw_rVHBDUb67WqJjL2odhj0ek81gYcpkFqVwDLe0rdd3Z0JoXAPTTL_vaXpvTY-05zuaJLLYk1ua078uotTVIGVehAlOk7W2Ar87HCPppCLb7CTEOTV03w4w=1=eb2a865d-4e9b-467f-aafa-354533b06f38> [cid:image030442.jpg@E0856E40.335029BE]<https://us.content.exclaimer.net/?url=https%3A%2F%2Felementmaterials.eu.qualtrics.com%2Fjfe%2Fform%2FSV_3xQqm84s6IydI5D=ixvYNdAGEeqbBQANOhMLNA=aabe0990b90beb1196f5000d3a130b34=gmElYo7_s0JlFVGqteg4_kVfS3mYohjNqcGed925oc0=U30r4FjO4qAnGLGxEYgrVj4Bg00SfIoY7ZRWmxKo0ae23QULQXwlyH7LsE723cGyQFQJrHJoE9nntmtc2Usy7WtguFAaA-2gYihpbfWltpcVhYVU_ZmJiDoHoCdgRsYnGGeL6j3V1uy8yBRfoFSB7QuOQqyuO6ERPvQyVD9zxvdGysyomtbORGLA_-ZAFr7IH04hCWr7XW5pwGx5nyXCKnGBA0kRcXNs6cWRfNDuxBDBUR2lTIDk8bZjewd-rTD9-cdSCAc1nWwUE3VgJyDDavNRrHlfu6w7lAFI_ralJkrvlDa8pGw8MFsb9Jro551bcafyklUNZ2S7DJltelheAQ=1=eb2a865d-4e9b-467f-aafa-354533b06f38> From: John Woodgate [mailto:j...@woodjohn.uk] Sent: Saturday, April 6, 2024 3:00 AM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] I would like to hear your thoughts please CAUTION:This email originated from outside of Element Materials Technology. DO NOT click links or open attachments unless you recognize the sender and know the content is safe. Please contact the TOC if you are in any doubt about this email. I agree: pre-scan is the way to go. Document all of the steps so that you can produce your reasons for your decision if challenged. On 2024-04-06 00:05, Brent DeWitt wrote: Tough one! The problem lies in the determination of "worst case". While it would be easy to presume that having all of the hardware populated is worst case, it overlooks the effects of un-terminated stubs and other SI related issues. In addition, with the world of firmware based PLL clocks and memory traffic, it is a tough thing to determine. My opinion would be to preform the simplest pre-scan on each configuration and base the final, rigorous certification based on that knowledge. Brent Dewitt Milford, MA On 4/5/2024 6:47 PM, Lfresearch wrote: Hi folks, I would like to advise a client at where to draw the line on what ne
Re: [PSES] I would like to hear your thoughts please
Dear All, Within the framework of the EMCD, all configurations shall be conform, so if you choose to actually test, all configurations shall be part of the test. The subject of worse case is a "miroir d'alouette"... how will you ever know which is worst case without carrying out the test ? A pre-scan is informative but the radiated emission test contains already a pre-scan (peak) for the final QP-measurement. We already require a EMC risk analysis which is a kind of pre-scan too. How many pre-pre-prescans will we need to be sure ? "to repeat _some_ (which?) test to make sure nothing was broken" it's another discipline, but that is how Boeing lost a door in flight. And that is not a unregulated sector without thorough quality scans (understatement), and still it happens. Imagine the costs and effort for Boeing to rebuild their reputation ? Didn't we all learned the exponential graph of EMC costs versus development time ? If you need proof (for authorities, or for yourself), nothing can replace the actual test. Gert Gremmen On 6-4-2024 0:47, Lfresearch wrote: Hi folks, I would like to advise a client at where to draw the line on what needs testing. I would like to solicit opinions besides my own. Otherwise it’s the fox urging the chicken coop… So a manufacturer that makes a product of which there will be several variants. All use the same board, but have different sections of circuits populated. This may require slightly different code to run on the same uP in each case. So.. The burning question is can we perform and analysis that postulates a worse case hardware/software combination and test just one configuration? Or, do we have to do every combination? Or, are there some guidelines about where we draw the line of what to test and what can be claimed as similarity? Off list responses are welcome too. Thanks, Derek Walton LFResearch/SSCLabs. - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail toemc-p...@listserv.ieee.org All emc-pstc postings are archived and searchable on the web at: https://www.mail-archive.com/emc-pstc@listserv.ieee.org/ Website:https://ewh.ieee.org/soc/pses/ Instructions:https://ewh.ieee.org/soc/pses/list.html (including how to unsubscribe) List rules:https://ewh.ieee.org/soc/pses/listrules.html For help, send mail to the list administrators: Mike Sherman at:msherma...@comcast.net Rick Linford at:linf...@ieee.org For policy questions, send mail to: Jim Bacher: _ To unsubscribe from the EMC-PSTC list, click the following link:https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC=1 -- Independent Expert on CE marking EMC Consultant Electrical Safety Consultant - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to EMC-PSTC@LISTSERV.IEEE.ORG All emc-pstc postings are archived and searchable on the web at: https://www.mail-archive.com/emc-pstc@listserv.ieee.org/ Website: https://ewh.ieee.org/soc/pses/ Instructions: https://ewh.ieee.org/soc/pses/list.html (including how to unsubscribe) List rules: https://ewh.ieee.org/soc/pses/listrules.html For help, send mail to the list administrators: Mike Sherman at: msherma...@comcast.net Rick Linford at: linf...@ieee.org For policy questions, send mail to: Jim Bacher: _ To unsubscribe from the EMC-PSTC list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC=1 BEGIN:VCARD FN:Gert Gremmen N:Gremmen;Gert;;; ADR:;;1261 Route de Pirot;Chauffailles;;71170;France EMAIL;PREF=1:g.grem...@cetest.nl TEL;TYPE=cell:+33 7 84507010 NOTE:Independent Expert on CE marking \n Harmonised Standards (HAS-) Consu ltant @ European Commission for RED\, LVD and EMC\n EMC Consultant\n Elect rical Safety Consultant\n X-MOZILLA-HTML:TRUE END:VCARD
Re: [PSES] I would like to hear your thoughts please
Hi Derek It is common practice within the labs to find worse case configuration and test it. At least we are doing it in such a way. You can find some guidlines how to form families on IECEE page, but I think your case is different. The best way is to test one fully populated product. Best regards Bostjan Glavic SIQ Poslano iz Outlook za Android<https://aka.ms/AAb9ysg> Od: Lfresearch <00734758d943-dmarc-requ...@listserv.ieee.org> Poslano: sobota, april 6, 2024 12:47:49 AM Za: EMC-PSTC@LISTSERV.IEEE.ORG Zadeva: [PSES] I would like to hear your thoughts please CAUTION: This email originated from outside of our organisation. Do not click links or open attachments unless you recognise the sender and know the content is safe. Hi folks, I would like to advise a client at where to draw the line on what needs testing. I would like to solicit opinions besides my own. Otherwise it’s the fox urging the chicken coop… So a manufacturer that makes a product of which there will be several variants. All use the same board, but have different sections of circuits populated. This may require slightly different code to run on the same uP in each case. So.. The burning question is can we perform and analysis that postulates a worse case hardware/software combination and test just one configuration? Or, do we have to do every combination? Or, are there some guidelines about where we draw the line of what to test and what can be claimed as similarity? Off list responses are welcome too. Thanks, Derek Walton LFResearch/SSCLabs. - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to EMC-PSTC@LISTSERV.IEEE.ORG All emc-pstc postings are archived and searchable on the web at: https://www.mail-archive.com/emc-pstc@listserv.ieee.org/ Website: https://ewh.ieee.org/soc/pses/ Instructions: https://ewh.ieee.org/soc/pses/list.html (including how to unsubscribe) List rules: https://ewh.ieee.org/soc/pses/listrules.html For help, send mail to the list administrators: Mike Sherman at: msherma...@comcast.net Rick Linford at: linf...@ieee.org For policy questions, send mail to: Jim Bacher: _ To unsubscribe from the EMC-PSTC list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC=1 - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to EMC-PSTC@LISTSERV.IEEE.ORG All emc-pstc postings are archived and searchable on the web at: https://www.mail-archive.com/emc-pstc@listserv.ieee.org/ Website: https://ewh.ieee.org/soc/pses/ Instructions: https://ewh.ieee.org/soc/pses/list.html (including how to unsubscribe) List rules: https://ewh.ieee.org/soc/pses/listrules.html For help, send mail to the list administrators: Mike Sherman at: msherma...@comcast.net Rick Linford at: linf...@ieee.org For policy questions, send mail to: Jim Bacher: _ To unsubscribe from the EMC-PSTC list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC=1
Re: [PSES] I would like to hear your thoughts please
Propose a sampling of configurations to the powers that may be. Don Gies Field Service Engineer GUTOR M: +1 346 313 6216 E: donald.g...@non.se.com 17 Capitol Reef Road Howell, NJ 07731 USA Sent by Android Phone General From: John Woodgate Sent: Saturday, April 6, 2024 3:59:57 AM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] I would like to hear your thoughts please [External email: Use caution with links and attachments] I agree: pre-scan is the way to go. Document all of the steps so that you can produce your reasons for your decision if challenged. On 2024-04-06 00:05, Brent DeWitt wrote: Tough one! The problem lies in the determination of "worst case". While it would be easy to presume that having all of the hardware populated is worst case, it overlooks the effects of un-terminated stubs and other SI related issues. In addition, with the world of firmware based PLL clocks and memory traffic, it is a tough thing to determine. My opinion would be to preform the simplest pre-scan on each configuration and base the final, rigorous certification based on that knowledge. Brent Dewitt Milford, MA On 4/5/2024 6:47 PM, Lfresearch wrote: Hi folks, I would like to advise a client at where to draw the line on what needs testing. I would like to solicit opinions besides my own. Otherwise it’s the fox urging the chicken coop… So a manufacturer that makes a product of which there will be several variants. All use the same board, but have different sections of circuits populated. This may require slightly different code to run on the same uP in each case. So.. The burning question is can we perform and analysis that postulates a worse case hardware/software combination and test just one configuration? Or, do we have to do every combination? Or, are there some guidelines about where we draw the line of what to test and what can be claimed as similarity? Off list responses are welcome too. Thanks, Derek Walton LFResearch/SSCLabs. - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to EMC-PSTC@LISTSERV.IEEE.ORG<mailto:EMC-PSTC@LISTSERV.IEEE.ORG> All emc-pstc postings are archived and searchable on the web at: https://www.mail-archive.com/emc-pstc@listserv.ieee.org/ Website: https://ewh.ieee.org/soc/pses/ Instructions: https://ewh.ieee.org/soc/pses/list.html (including how to unsubscribe) List rules: https://ewh.ieee.org/soc/pses/listrules.html For help, send mail to the list administrators: Mike Sherman at: msherma...@comcast.net<mailto:msherma...@comcast.net> Rick Linford at: linf...@ieee.org<mailto:linf...@ieee.org> For policy questions, send mail to: Jim Bacher: <mailto:j.bac...@ieee.org> _ To unsubscribe from the EMC-PSTC list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC=1 - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to EMC-PSTC@LISTSERV.IEEE.ORG<mailto:EMC-PSTC@LISTSERV.IEEE.ORG> All emc-pstc postings are archived and searchable on the web at: https://www.mail-archive.com/emc-pstc@listserv.ieee.org/ Website: https://ewh.ieee.org/soc/pses/ Instructions: https://ewh.ieee.org/soc/pses/list.html (including how to unsubscribe) List rules: https://ewh.ieee.org/soc/pses/listrules.html For help, send mail to the list administrators: Mike Sherman at: msherma...@comcast.net<mailto:msherma...@comcast.net> Rick Linford at: linf...@ieee.org<mailto:linf...@ieee.org> For policy questions, send mail to: Jim Bacher: <mailto:j.bac...@ieee.org> _ To unsubscribe from the EMC-PSTC list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC=1 -- OOO - Own Opinions Only Best wishes John Woodgate, Rayleigh, Essex UK Keep trying [https://s-install.avcdn.net/ipm/preview/icons/icon-envelope-tick-green-avg-v1.png]<http://www.avg.com/email-signature?utm_medium=email_source=link_campaign=sig-email_content=emailclient> Virus-free.www.avg.com<http://www.avg.com/email-signature?utm_medium=email_source=link_campaign=sig-email_content=emailclient> This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to EMC-PSTC@LISTSERV.IEEE.ORG All emc-pstc postings are archived and searchable on the web at: https://www.mail-archive.com/emc-pstc@listserv.ieee.org/ Website: https://ewh.ieee.org/soc/pses/ Instructions: https://ewh.ieee.org/soc/pses/list.html (including ho
Re: [PSES] I would like to hear your thoughts please
I agree: pre-scan is the way to go. Document all of the steps so that you can produce your reasons for your decision if challenged. On 2024-04-06 00:05, Brent DeWitt wrote: Tough one! The problem lies in the determination of "worst case". While it would be easy to presume that having all of the hardware populated is worst case, it overlooks the effects of un-terminated stubs and other SI related issues. In addition, with the world of firmware based PLL clocks and memory traffic, it is a tough thing to determine. My opinion would be to preform the simplest pre-scan on each configuration and base the final, rigorous certification based on that knowledge. Brent Dewitt Milford, MA On 4/5/2024 6:47 PM, Lfresearch wrote: Hi folks, I would like to advise a client at where to draw the line on what needs testing. I would like to solicit opinions besides my own. Otherwise it’s the fox urging the chicken coop… So a manufacturer that makes a product of which there will be several variants. All use the same board, but have different sections of circuits populated. This may require slightly different code to run on the same uP in each case. So.. The burning question is can we perform and analysis that postulates a worse case hardware/software combination and test just one configuration? Or, do we have to do every combination? Or, are there some guidelines about where we draw the line of what to test and what can be claimed as similarity? Off list responses are welcome too. Thanks, Derek Walton LFResearch/SSCLabs. - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to EMC-PSTC@LISTSERV.IEEE.ORG All emc-pstc postings are archived and searchable on the web at: https://www.mail-archive.com/emc-pstc@listserv.ieee.org/ Website: https://ewh.ieee.org/soc/pses/ Instructions: https://ewh.ieee.org/soc/pses/list.html (including how to unsubscribe) List rules: https://ewh.ieee.org/soc/pses/listrules.html For help, send mail to the list administrators: Mike Sherman at: msherma...@comcast.net Rick Linford at: linf...@ieee.org For policy questions, send mail to: Jim Bacher: _ To unsubscribe from the EMC-PSTC list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC=1 - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to EMC-PSTC@LISTSERV.IEEE.ORG All emc-pstc postings are archived and searchable on the web at: https://www.mail-archive.com/emc-pstc@listserv.ieee.org/ Website: https://ewh.ieee.org/soc/pses/ Instructions: https://ewh.ieee.org/soc/pses/list.html (including how to unsubscribe) List rules: https://ewh.ieee.org/soc/pses/listrules.html For help, send mail to the list administrators: Mike Sherman at: msherma...@comcast.net Rick Linford at: linf...@ieee.org For policy questions, send mail to: Jim Bacher: _ To unsubscribe from the EMC-PSTC list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC=1 -- Signature OOO - Own Opinions Only Best wishes John Woodgate, Rayleigh, Essex UK Keep trying -- This email has been checked for viruses by AVG antivirus software. www.avg.com - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to EMC-PSTC@LISTSERV.IEEE.ORG All emc-pstc postings are archived and searchable on the web at: https://www.mail-archive.com/emc-pstc@listserv.ieee.org/ Website: https://ewh.ieee.org/soc/pses/ Instructions: https://ewh.ieee.org/soc/pses/list.html (including how to unsubscribe) List rules: https://ewh.ieee.org/soc/pses/listrules.html For help, send mail to the list administrators: Mike Sherman at: msherma...@comcast.net Rick Linford at: linf...@ieee.org For policy questions, send mail to: Jim Bacher: _ To unsubscribe from the EMC-PSTC list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC=1
Re: [PSES] I would like to hear your thoughts please
That has been my experience with CB Scheme, E-mark, and product safety in the USA using an NRTL. Namely, pick worst-case with justifications, talk with your certifier, and reach an understanding. If they won't budge and insist on full testing of every variant, move to another certifier who is willing to listen to reason. If the "code" is different and your firmware is a functional safety component, then you may not have much choice but to repeat at least some of the tests called out in the test plan to verify nothing was "broken" when tweaking the firmware to accommodate each hardware variant. Ralph -Original Message- From: Lfresearch <00734758d943-dmarc-requ...@listserv.ieee.org> Sent: Friday, April 5, 2024 3:47 PM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: [PSES] I would like to hear your thoughts please Hi folks, I would like to advise a client at where to draw the line on what needs testing. I would like to solicit opinions besides my own. Otherwise it’s the fox urging the chicken coop… So a manufacturer that makes a product of which there will be several variants. All use the same board, but have different sections of circuits populated. This may require slightly different code to run on the same uP in each case. So.. The burning question is can we perform and analysis that postulates a worse case hardware/software combination and test just one configuration? Or, do we have to do every combination? Or, are there some guidelines about where we draw the line of what to test and what can be claimed as similarity? Off list responses are welcome too. Thanks, Derek Walton LFResearch/SSCLabs. - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to EMC-PSTC@LISTSERV.IEEE.ORG All emc-pstc postings are archived and searchable on the web at: https://www.mail-archive.com/emc-pstc@listserv.ieee.org/ Website: https://ewh.ieee.org/soc/pses/ Instructions: https://ewh.ieee.org/soc/pses/list.html (including how to unsubscribe) List rules: https://ewh.ieee.org/soc/pses/listrules.html For help, send mail to the list administrators: Mike Sherman at: msherma...@comcast.net Rick Linford at: linf...@ieee.org For policy questions, send mail to: Jim Bacher: _ To unsubscribe from the EMC-PSTC list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC=1 - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to EMC-PSTC@LISTSERV.IEEE.ORG All emc-pstc postings are archived and searchable on the web at: https://www.mail-archive.com/emc-pstc@listserv.ieee.org/ Website: https://ewh.ieee.org/soc/pses/ Instructions: https://ewh.ieee.org/soc/pses/list.html (including how to unsubscribe) List rules: https://ewh.ieee.org/soc/pses/listrules.html For help, send mail to the list administrators: Mike Sherman at: msherma...@comcast.net Rick Linford at: linf...@ieee.org For policy questions, send mail to: Jim Bacher: _ To unsubscribe from the EMC-PSTC list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC=1
Re: [PSES] I would like to hear your thoughts please
Tough one! The problem lies in the determination of "worst case". While it would be easy to presume that having all of the hardware populated is worst case, it overlooks the effects of un-terminated stubs and other SI related issues. In addition, with the world of firmware based PLL clocks and memory traffic, it is a tough thing to determine. My opinion would be to preform the simplest pre-scan on each configuration and base the final, rigorous certification based on that knowledge. Brent Dewitt Milford, MA On 4/5/2024 6:47 PM, Lfresearch wrote: Hi folks, I would like to advise a client at where to draw the line on what needs testing. I would like to solicit opinions besides my own. Otherwise it’s the fox urging the chicken coop… So a manufacturer that makes a product of which there will be several variants. All use the same board, but have different sections of circuits populated. This may require slightly different code to run on the same uP in each case. So.. The burning question is can we perform and analysis that postulates a worse case hardware/software combination and test just one configuration? Or, do we have to do every combination? Or, are there some guidelines about where we draw the line of what to test and what can be claimed as similarity? Off list responses are welcome too. Thanks, Derek Walton LFResearch/SSCLabs. - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to EMC-PSTC@LISTSERV.IEEE.ORG All emc-pstc postings are archived and searchable on the web at: https://www.mail-archive.com/emc-pstc@listserv.ieee.org/ Website: https://ewh.ieee.org/soc/pses/ Instructions: https://ewh.ieee.org/soc/pses/list.html (including how to unsubscribe) List rules: https://ewh.ieee.org/soc/pses/listrules.html For help, send mail to the list administrators: Mike Sherman at: msherma...@comcast.net Rick Linford at: linf...@ieee.org For policy questions, send mail to: Jim Bacher: _ To unsubscribe from the EMC-PSTC list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC=1 - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to EMC-PSTC@LISTSERV.IEEE.ORG All emc-pstc postings are archived and searchable on the web at: https://www.mail-archive.com/emc-pstc@listserv.ieee.org/ Website: https://ewh.ieee.org/soc/pses/ Instructions: https://ewh.ieee.org/soc/pses/list.html (including how to unsubscribe) List rules: https://ewh.ieee.org/soc/pses/listrules.html For help, send mail to the list administrators: Mike Sherman at: msherma...@comcast.net Rick Linford at: linf...@ieee.org For policy questions, send mail to: Jim Bacher: _ To unsubscribe from the EMC-PSTC list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC=1
[PSES] I would like to hear your thoughts please
Hi folks, I would like to advise a client at where to draw the line on what needs testing. I would like to solicit opinions besides my own. Otherwise it’s the fox urging the chicken coop… So a manufacturer that makes a product of which there will be several variants. All use the same board, but have different sections of circuits populated. This may require slightly different code to run on the same uP in each case. So.. The burning question is can we perform and analysis that postulates a worse case hardware/software combination and test just one configuration? Or, do we have to do every combination? Or, are there some guidelines about where we draw the line of what to test and what can be claimed as similarity? Off list responses are welcome too. Thanks, Derek Walton LFResearch/SSCLabs. - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to EMC-PSTC@LISTSERV.IEEE.ORG All emc-pstc postings are archived and searchable on the web at: https://www.mail-archive.com/emc-pstc@listserv.ieee.org/ Website: https://ewh.ieee.org/soc/pses/ Instructions: https://ewh.ieee.org/soc/pses/list.html (including how to unsubscribe) List rules: https://ewh.ieee.org/soc/pses/listrules.html For help, send mail to the list administrators: Mike Sherman at: msherma...@comcast.net Rick Linford at: linf...@ieee.org For policy questions, send mail to: Jim Bacher: _ To unsubscribe from the EMC-PSTC list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC=1
