Re: Conducted Emissions Test in Telephones
Joe and Group, Thanks for your answers. But I think I should refine some points where I still have some doubts. I'll try to put my doubts in topic mode, for a matter of clarity: - The case is this: I have a Telephone Set (wired to the Public Telephony Network). And I'd like to sell it to markets where the EMC laws are mandatory. - What Standards apply for this kind of product?? (FCC XXX, EN XXX)?? - Does this kind of equipment need to be tested for electromagnetic emissions (conducted and radiated)??? Its only supply is the Public Telephony Network, that in Brazil supplies a voltage of 48Vdc. - In the case of MUST BE TESTED for conducted and radiated emissions, how should I realize the test? With the phone in idle mode, in receiving mode, in making call mode??? Or all of the previous modes? Well, it's all for the moment. Thanks in advance for those who help. Best Regards Muriel *** Muriel Bittencourt de Liz - Test Engineer Lab of Applied Electromagnetism for Engineering Dept. of Electrical Engineering Federal University at Santa Catarina State Florianópolis, Santa Catarina State Brazil In a message dated 6/28/01, Geoff Lister writes: EN55022:1998 section 9.5 indicates that measurements must be made on telecommunication ports, and covers, in great detail how this should be done. Hi Muriel: Geoff has provided a succinct answer to the question you posed. I just want to add that you will also have to test for immunity per EN 55024 if you plan to CE mark your product. This standard includes about seven different immunity tests (static discharge, lightning, etc.). Of the tests included in EN 55024, perhaps the most difficult is the conducted immunity test. For this test, common mode RF signals of 3 VRMS, 150 KHz to 80 MHz, are applied to the phone line. The RF carrier is 80% AM modulated at 1 KHz to simulate an AM radio station. Limits are placed on the amount of demodulated 1 KHz that appears on the phone line and in the handset. My experience with this new test suggests that most conventional telephone designs will have difficulty passing. You may need to add some special filtering in strategic locations order to pass. Joe Randolph Telecom Design Consultant Randolph Telecom, Inc. 781-721-2848 http://www.randolph-telecom.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: http://www.rcic.com/ click on Virtual Conference Hall,
Re: Conducted Emissions Test in Telephones
In a message dated 6/28/01, Geoff Lister writes: EN55022:1998 section 9.5 indicates that measurements must be made on telecommunication ports, and covers, in great detail Hi Muriel: Geoff has provided a succinct answer to the question you posed. I just want to add that you will also have to test for immunity per EN 55024 if you plan to CE mark your product. This standard includes about seven different immunity tests (static discharge, lightning, etc.). Of the tests included in EN 55024, perhaps the most difficult is the conducted immunity test. For this test, common mode RF signals of 3 VRMS, 150 KHz to 80 MHz, are applied to the phone line. The RF carrier is 80% AM modulated at 1 KHz to simulate an AM radio station. Limits are placed on the amount of demodulated 1 KHz that appears on the phone line and in the handset. My experience with this new test suggests that most conventional telephone designs will have difficulty passing. You may need to add some special filtering in strategic locations order to pass. Joe Randolph Telecom Design Consultant Randolph Telecom, Inc. 781-721-2848 http://www.randolph-telecom.com
RE: Conducted Emissions Test in Telephones
Muriel, EN55022:1998 section 9.5 indicates that measurements must be made on telecommunication ports, and covers, in great detail how this should be done. Section 8.2 starts with The operational conditions of the EUT shall be determined by the manufacturer according to the typical use of the EUT with respect to the expected highest level of emission. So, you should check both at standby and active for the highest levels. Other CISPR 22 related specifications may differ, but you will need to test for countries using the EN specs. Best regards, Geoff Lister (geoff.lis...@motion-media.com) Senior Engineer Motion Media Technology Ltd. Horton Hall, Horton, Bristol, BS37 6QN, UK Voice direct +44 (0) 1454 338561 Voice switchboard +44 (0) 1454 313444 Fax +44 (0) 1454 313678 http://www.motion-media.com -Original Message- From: Muriel Bittencourt de Liz [mailto:mur...@eel.ufsc.br] Sent: 27 June 2001 22:57 To: EMC-PSTC List Subject: Conducted Emissions Test in Telephones Hello Group, I'd like to know if telephone devices (plain telephone devices) must be tested for conducted emissions (CISPR 22, Class B). And if they must, what is the proceeding for testing them? Should I test with the telephone in stand-by (no calls) or during a call?? Thanks in advance for the answers. Best Regards Muriel --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.rcic.com/ click on Virtual Conference Hall, --- Incoming mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.261 / Virus Database: 131 - Release Date: 06/06/01 --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.rcic.com/ click on Virtual Conference Hall,
Conducted Emissions Test in Telephones
Hello Group, I'd like to know if telephone devices (plain telephone devices) must be tested for conducted emissions (CISPR 22, Class B). And if they must, what is the proceeding for testing them? Should I test with the telephone in stand-by (no calls) or during a call?? Thanks in advance for the answers. Best Regards Muriel --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.rcic.com/ click on Virtual Conference Hall,
