[PSES] IEC 61000-4-5:2014/AMD1:2017 - Using the correct CDN for AC mains testing
Greetings colleagues, Thank-you to all those who have responded to my in inquiry. I appreciate that you have taken the time to send in a response with good technical advice. Thank-you again, Richard Georgerian Applications Engineer From: Richard Georgerian Sent: Tuesday, April 2, 2019 12:15 PM To: 'EMC-PSTC@LISTSERV.IEEE.ORG' Subject: IEC 61000-4-5:2014/AMD1:2017 - Using the correct CDN for AC mains testing Greeting colleagues, Hopefully, someone in the PSTC group can correct my rational below and enlighten me on the finer points of CDNs. The discussion within our applications group is, shall the EUT current rating be correctly matched to the CDN current rating? For example, don't use a CDN rated for 32 A for a EUT that is rated for 2 A, to ensure that the correct Surge waveform will be applied to the EUT. I cannot think of a good rational why a CDN rated for 32 A cannot be used for a EUT rated for 2 A. We do understand that for the different current ratings of CDNs, 16 A, 32 A, 63A and 125 A, the internal components must have different values to meet the Surge waveform, for Open circuit and Short circuit. However, testing Open circuit and Short circuit on a CDN is without applying any currrent through the CDN, so in effect, the Surge waveform for a 16 A CDN and a Surge waveform for a 32 A CDN should have the same effect on a EUT drawing only 2 A of current. Probably two questions would help in trying to explain what our discussion is about. Must we use a CDN rated for 32 A, for products with a current rating between 16 A and 32 A, to be considered being compliant to IEC 61000-4-5, for AC mains surge testing? Must we use a CDN rated for 16 A, for products with a current rating less than or equal to 16 A, to be considered being compliant to IEC 61000-4-5, for AC mains surge testing? In the IEC 61000-4-5:2014, Section 7.3 Test setup for surges applied to EUT power ports - "The selection of the CDN specification from Table 4 shall be made to match the current rating of the EUT (for example: an EUT rated at 5 A shall be tested using a CDN complying with the specifications of a 16 A rated CDN). Any higher current rated CDN can be used if it meets the specification requirements in Table 4 for the relevant lower current rating of the EUT (for example: a CDN rated 64 A can be used for testing an EUT rated at 5 A, if it meets the specification requirements of a 16 A rated CDN)." So maybe I answered my questions. Thank-you, Richard Georgerian Applications Engineer - 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 All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe) List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas Mike Cantwell For policy questions, send mail to: Jim Bacher: David Heald:
Re: [PSES] IEC 61000-4-5:2014/AMD1:2017 - Using the correct CDN for AC mains testing
As an aside, when you come to CDNs for DC systems, things can become more complicated and interesting. The AMD1 came about after the US National Committee commented "“The method for testing DC products in the current revision of IEC61000-4-5 is causing many field related problems for test labs and manufacturers. Many products will not power up through the power CDN in the standard and in some cases may be damaged by the inductance that is necessary to apply the surge." It is easy to understand why. The large series inductance of the CDN presents a high pulse impedance, which prevents rapid changes of current, which is abnormal to the normal system configuration. Electronic loads like converters and inverters expect a reasonably low impedance supply to start and operate. AMD1, in the body text, allows the use of a larger current-rated CDN with ratings ≤125 A and in Annex I (informative), Issues relating to powering EUT’s having DC-DC converters on their inputs, suggests a damping circuit for reducing possible oscillations. Example CDN component values can be found by searching for papers like "Influence of Power-Line Coupling/Decoupling Network on Output Characteristics of the Combination Wave Generator" and "Coupling and decoupling network for surge immunity test on power lines" In such a DC system using a CDN whose values force the majority of the surge stress on the EUT can result in unrealistic surge conditions. The ITU-T currently opts for a two way approach. Existing CDN arrangements are grandfathered while giving the test option of using a CDN with values that reflect the longest connecting cable thus implementing a system surge test rather than an individual equipment surge test. The ITU-T has devised an interesting test circuit that imposes a common-mode surge on both supply polarities. Any system polarity earthing and the presence of any voltage limiting functions condition the resultant surge on the system to be common-mode, differential mode or a mixture of both. Regards, Mick Maytum Safety and Telecom Standards mjmay...@gmail.com https://ict-surge-protection-essays.co.uk/ -- Original Message -- From: "David Schaefer" To: EMC-PSTC@listserv.ieee.org Sent: 02/04/2019 20:40:24 Subject: Re: [PSES] IEC 61000-4-5:2014/AMD1:2017 - Using the correct CDN for AC mains testing A higher current rated CDN can be used, but only if it meets the lower current CDN’s waveform requirements. From the quoted section: “Any higher current rated CDN can be used if it meets the specification requirements in Table 4 for the relevant lower current rating of the EUT (for example: a CDN rated 64 A can be used for testing an EUT rated at 5 A, if it meets the specification requirements of a 16 A rated CDN).” The reason for this is higher current CDNs are allowed to have pulse widths significantly shorter than lower ratings. Check out Table 4 of the 2014 edition. A 16 amp CDN differential mode pulse width is required to be 50 us +/- 10 us. A 125 Amp CDN is 50 us +10 us/-30 us. So yes, a 64 amp CDN can be used with a 5 amp product, if it meets the 50 us +/- 10 us requirement. Thanks, ELEMENT__15px.jpeg David Schaefer Department Manager, EMC Element Materials Technology 9349 W Broadway Ave Brooklyn Park, MN 55445, United States O +1 612 638 5136 ext. 4003 david.schae...@element.com www.element.com LINKEDIN.jpeg <https://www.linkedin.com/company/element-materials-technology/> TWITTER.jpeg <https://twitter.com/ElementTesting/> <https://www.element.com/about-element/growth-acquisitions/exova-group-plc> From: John Woodgate [mailto:j...@woodjohn.uk] Sent: Tuesday, April 2, 2019 2:12 PM To:EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] IEC 61000-4-5:2014/AMD1:2017 - Using the correct CDN for AC mains testing I think you did (answer your own question). The text you quote seems surprisingly (and gratifyingly) lucid. Under 16 A use a 16 A CDN. Over 16 A up to 32 A, use a 32 A CDN. Best wishes John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2019-04-02 19:14, Richard Georgerian wrote: Greeting colleagues, Hopefully, someone in the PSTC group can correct my rational below and enlighten me on the finer points of CDNs. The discussion within our applications group is, shall the EUT current rating be correctly matched to the CDN current rating? For example, don’t use a CDN rated for 32 A for a EUT that is rated for 2 A, to ensure that the correct Surge waveform will be applied to the EUT. I cannot think of a good rational why a CDN rated for 32 A cannot be used for a EUT rated for 2 A. We do understand that for the different current ratings of CDNs, 16 A, 32 A, 63A and 125 A, the internal components must have different values to meet the Surge waveform, for Open circuit and Short circuit. However, testing Open c
Re: [PSES] IEC 61000-4-5:2014/AMD1:2017 - Using the correct CDN for AC mains testing
A higher current rated CDN can be used, but only if it meets the lower current CDN's waveform requirements. From the quoted section: "Any higher current rated CDN can be used if it meets the specification requirements in Table 4 for the relevant lower current rating of the EUT (for example: a CDN rated 64 A can be used for testing an EUT rated at 5 A, if it meets the specification requirements of a 16 A rated CDN)." The reason for this is higher current CDNs are allowed to have pulse widths significantly shorter than lower ratings. Check out Table 4 of the 2014 edition. A 16 amp CDN differential mode pulse width is required to be 50 us +/- 10 us. A 125 Amp CDN is 50 us +10 us/-30 us. So yes, a 64 amp CDN can be used with a 5 amp product, if it meets the 50 us +/- 10 us requirement. Thanks, David Schaefer Department Manager, EMC Element Materials Technology 9349 W Broadway Ave Brooklyn Park, MN 55445, United States O +1 612 638 5136 ext. 4003 david.schae...@element.com www.element.com From: John Woodgate [mailto:j...@woodjohn.uk] Sent: Tuesday, April 2, 2019 2:12 PM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] IEC 61000-4-5:2014/AMD1:2017 - Using the correct CDN for AC mains testing I think you did (answer your own question). The text you quote seems surprisingly (and gratifyingly) lucid. Under 16 A use a 16 A CDN. Over 16 A up to 32 A, use a 32 A CDN. Best wishes John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk<http://www.woodjohn.uk> Rayleigh, Essex UK On 2019-04-02 19:14, Richard Georgerian wrote: Greeting colleagues, Hopefully, someone in the PSTC group can correct my rational below and enlighten me on the finer points of CDNs. The discussion within our applications group is, shall the EUT current rating be correctly matched to the CDN current rating? For example, don't use a CDN rated for 32 A for a EUT that is rated for 2 A, to ensure that the correct Surge waveform will be applied to the EUT. I cannot think of a good rational why a CDN rated for 32 A cannot be used for a EUT rated for 2 A. We do understand that for the different current ratings of CDNs, 16 A, 32 A, 63A and 125 A, the internal components must have different values to meet the Surge waveform, for Open circuit and Short circuit. However, testing Open circuit and Short circuit on a CDN is without applying any currrent through the CDN, so in effect, the Surge waveform for a 16 A CDN and a Surge waveform for a 32 A CDN should have the same effect on a EUT drawing only 2 A of current. Probably two questions would help in trying to explain what our discussion is about. Must we use a CDN rated for 32 A, for products with a current rating between 16 A and 32 A, to be considered being compliant to IEC 61000-4-5, for AC mains surge testing? Must we use a CDN rated for 16 A, for products with a current rating less than or equal to 16 A, to be considered being compliant to IEC 61000-4-5, for AC mains surge testing? In the IEC 61000-4-5:2014, Section 7.3 Test setup for surges applied to EUT power ports - "The selection of the CDN specification from Table 4 shall be made to match the current rating of the EUT (for example: an EUT rated at 5 A shall be tested using a CDN complying with the specifications of a 16 A rated CDN). Any higher current rated CDN can be used if it meets the specification requirements in Table 4 for the relevant lower current rating of the EUT (for example: a CDN rated 64 A can be used for testing an EUT rated at 5 A, if it meets the specification requirements of a 16 A rated CDN)." So maybe I answered my questions. Thank-you, Richard Georgerian Applications Engineer - 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 mailto:emc-p...@ieee.org>> All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html<http://www.ieee-pses.org/emc-pstc.html> Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/<http://product-compliance.oc.ieee.org/> can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/<http://www.ieee-pses.org/> Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe)<http://www.ieee-pses.org/list.html> List rules: http://www.ieee-pses.org/listrules.html<http://www.ieee-pses.org/listrules.html> For help, send mail to the list administrators: Scott Douglas mailto:sdoug...@ieee.org>> Mike Cantwell mailto:mcantw...@ieee.org>> For policy questions, send mail to: Jim Bacher mailto:j.bac...@ieee.org>> David Heald mailto:dhe...@gmail.com>> - This
Re: [PSES] IEC 61000-4-5:2014/AMD1:2017 - Using the correct CDN for AC mains testing
I think you did (answer your own question). The text you quote seems surprisingly (and gratifyingly) lucid. Under 16 A use a 16 A CDN. Over 16 A up to 32 A, use a 32 A CDN. Best wishes John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2019-04-02 19:14, Richard Georgerian wrote: Greeting colleagues, Hopefully, someone in the PSTC group can correct my rational below and enlighten me on the finer points of CDNs. The discussion within our applications group is, shall the EUT current rating be correctly matched to the CDN current rating? For example, don’t use a CDN rated for 32 A for a EUT that is rated for 2 A, to ensure that the correct Surge waveform will be applied to the EUT. I cannot think of a good rational why a CDN rated for 32 A cannot be used for a EUT rated for 2 A. We do understand that for the different current ratings of CDNs, 16 A, 32 A, 63A and 125 A, the internal components must have different values to meet the Surge waveform, for Open circuit and Short circuit. However, testing Open circuit and Short circuit on a CDN is without applying any currrent through the CDN, so in effect, the Surge waveform for a 16 A CDN and a Surge waveform for a 32 A CDN should have the same effect on a EUT drawing only 2 A of current. Probably two questions would help in trying to explain what our discussion is about. Must we use a CDN rated for 32 A, for products with a current rating between 16 A and 32 A, to be considered being compliant to IEC 61000-4-5, for AC mains surge testing? Must we use a CDN rated for 16 A, for products with a current rating less than or equal to 16 A, to be considered being compliant to IEC 61000-4-5, for AC mains surge testing? In the IEC 61000-4-5:2014, Section 7.3 Test setup for surges applied to EUT power ports – “The selection of the CDN specification from Table 4 shall be made to match the current rating of the EUT (for example: an EUT rated at 5 A shall be tested using a CDN complying with the specifications of a 16 A rated CDN). Any higher current rated CDN can be used if it meets the specification requirements in Table 4 for the relevant lower current rating of the EUT (for example: a CDN rated 64 A can be used for testing an EUT rated at 5 A, if it meets the specification requirements of a 16 A rated CDN).” So maybe I answered my questions. Thank-you, Richard Georgerian Applications Engineer - 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 mailto:emc-p...@ieee.org>> All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe) List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas mailto:sdoug...@ieee.org>> Mike Cantwell mailto:mcantw...@ieee.org>> For policy questions, send mail to: Jim Bacher mailto:j.bac...@ieee.org>> David Heald mailto:dhe...@gmail.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 All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe) List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas Mike Cantwell For policy questions, send mail to: Jim Bacher: David Heald:
[PSES] IEC 61000-4-5:2014/AMD1:2017 - Using the correct CDN for AC mains testing
Greeting colleagues, Hopefully, someone in the PSTC group can correct my rational below and enlighten me on the finer points of CDNs. The discussion within our applications group is, shall the EUT current rating be correctly matched to the CDN current rating? For example, don't use a CDN rated for 32 A for a EUT that is rated for 2 A, to ensure that the correct Surge waveform will be applied to the EUT. I cannot think of a good rational why a CDN rated for 32 A cannot be used for a EUT rated for 2 A. We do understand that for the different current ratings of CDNs, 16 A, 32 A, 63A and 125 A, the internal components must have different values to meet the Surge waveform, for Open circuit and Short circuit. However, testing Open circuit and Short circuit on a CDN is without applying any currrent through the CDN, so in effect, the Surge waveform for a 16 A CDN and a Surge waveform for a 32 A CDN should have the same effect on a EUT drawing only 2 A of current. Probably two questions would help in trying to explain what our discussion is about. Must we use a CDN rated for 32 A, for products with a current rating between 16 A and 32 A, to be considered being compliant to IEC 61000-4-5, for AC mains surge testing? Must we use a CDN rated for 16 A, for products with a current rating less than or equal to 16 A, to be considered being compliant to IEC 61000-4-5, for AC mains surge testing? In the IEC 61000-4-5:2014, Section 7.3 Test setup for surges applied to EUT power ports - "The selection of the CDN specification from Table 4 shall be made to match the current rating of the EUT (for example: an EUT rated at 5 A shall be tested using a CDN complying with the specifications of a 16 A rated CDN). Any higher current rated CDN can be used if it meets the specification requirements in Table 4 for the relevant lower current rating of the EUT (for example: a CDN rated 64 A can be used for testing an EUT rated at 5 A, if it meets the specification requirements of a 16 A rated CDN)." So maybe I answered my questions. Thank-you, Richard Georgerian Applications Engineer - 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 All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe) List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas Mike Cantwell For policy questions, send mail to: Jim Bacher: David Heald:
