Re: Company close down due to EMC phenomena
A ROM (rough order of magnitude) estimate of magnetic radiation from power lines at 1 km yields a very small magnetic field. I used H = I/(6.28*r) with I = V/R and r = 1 km. I assumed V = 1 Volt and R = 100 Ohms to yield an I = 10 mA. Then H is on the order of 1 uA/m , very close to 1 pT which is well below the threshold of sensitivity of the ADF radio connected to the ADF loop. -- From: Mike Hopkins mhopk...@thermokeytek.com To: 'Ken Javor' ken.ja...@emccompliance.com, am...@westin-emission.no, emc-p...@majordomo.ieee.org Subject: RE: Company close down due to EMC phenomena Date: Thu, Jan 17, 2002, 12:25 PM Although there is no AM broadcast below 530kHz, there are still many services using the frequencies between 200kHz and 530kHz, the most important of which is the aviation industry. Called NDB's, these low frequency signals are still used for navigation globally and instrument approaches in airports world-wide. From a vantage point several thousand feet above the local power lines, a 25ms burst once/hour would be no big deal, but if there are lots of 25ms bursts/hour in a given area, this could be a problem! Mike Hopkins Thermo KeyTek (pilot of small airplane who does not want the ADF needle going around in circles -- especially when in use by pilot trying to figure out which way's home) -Original Message- From: Ken Javor [mailto:ken.ja...@emccompliance.com] Sent: Wednesday, January 16, 2002 4:53 PM To: am...@westin-emission.no; emc-p...@majordomo.ieee.org Subject: Re: Company close down due to EMC phenomena A technical response from an American. I sympathize with the viewpoint that the duty cycle is very low and the on-time is very low and the potential for mischief is near nil. I would add a further argument. 55022 CE limits protect AM radio reception. In the USA there is no AM broadcast below 530 kHz. In the EU there is some LW broadcasting from I believe 150 - 300 kHz, and then MW picks up again at 530 kHz. So the potential for rfi is limited. That officials would even consider banning such a product is an argument against anyone having such power. -- From: am...@westin-emission.no To: emc-p...@majordomo.ieee.org Subject: Company close down due to EMC phenomena Date: Wed, Jan 16, 2002, 2:17 PM Well, this might be the reality in a case I have been introduced to lately. Case: A company are manufacturing PowerLine Communication products. They communicate via the power lines and a typical link is between a consumer residence and the nearest power station. The products can of course also communicate inside the consumers residence. The communication protocol is called CEBus http://www.cebus.org/which and make use of the frequency band 100kHz-400kHz and the amplitude is approximate 2-5V. A typical length of a transmission is 25ms and occurs approximate one time pr hour. First of all, AFAIK PowerLine Communication and PowerLine Transmission (broadband 1.6MHz-30MHz) are now coming will full force in EU and CENELEC/ETSI are working together regulate this type of transmission path and also coming up with standards. The problem for the manufacturer is the conducted emission requirements in EU. According to the EN55022B levels the maximum quasi-peak emission is 66dBuV@150kHz, and a typical PLC (under transmission) which has been measured, showed the value of 120dBuV (peak). With no transmission it had a margin of 10dB (quasi-peak) and 30dB (average). The radiated emission had a margin of 10dB. Well, conducted emission is the problem when transmitting. But, as I said, the transmission occurs only 25ms/hour. The national authority will not allowed this product to be placed into the marked because it do not fulfil the EN55022B limits (100kHz-400kHz) under transmission mode. No way. Other national authorities have other approaches on this case, they say as long as you do not disturb other equipment, install it. If you do disturb, we will come and remove it. They also say install it even if it does not fulfil EN550022B, but we will remove it if it disturb others. Two completely different approaches as you see. Questions: 1. Is it possible to have different approaches within EU ? 2. Since PLC/PLT is quite new technology and since we do not have any EU product standard (no standard for whose who are using 100kHz-400kHz band), I like the approach as long as you do not disturb other equipment, install it. If you do disturb, we will come and remove it. What is your opinion about this? 3. The transmission occurs very seldom. 25ms/hour, that is 7e-6 and approximate 0,001% transmission rate. Can this seldom transmission rate be an argument to not test the PLC product under continuous transmission ? I would say yes, but which rate is acceptable / reasonable ? So, why should the company close down ? Because if the national authority gets what they want, there will be one sale. Logical
RE: Company close down due to EMC phenomena
Although there is no AM broadcast below 530kHz, there are still many services using the frequencies between 200kHz and 530kHz, the most important of which is the aviation industry. Called NDB's, these low frequency signals are still used for navigation globally and instrument approaches in airports world-wide. From a vantage point several thousand feet above the local power lines, a 25ms burst once/hour would be no big deal, but if there are lots of 25ms bursts/hour in a given area, this could be a problem! Mike Hopkins Thermo KeyTek (pilot of small airplane who does not want the ADF needle going around in circles -- especially when in use by pilot trying to figure out which way's home) -Original Message- From: Ken Javor [mailto:ken.ja...@emccompliance.com] Sent: Wednesday, January 16, 2002 4:53 PM To: am...@westin-emission.no; emc-p...@majordomo.ieee.org Subject: Re: Company close down due to EMC phenomena A technical response from an American. I sympathize with the viewpoint that the duty cycle is very low and the on-time is very low and the potential for mischief is near nil. I would add a further argument. 55022 CE limits protect AM radio reception. In the USA there is no AM broadcast below 530 kHz. In the EU there is some LW broadcasting from I believe 150 - 300 kHz, and then MW picks up again at 530 kHz. So the potential for rfi is limited. That officials would even consider banning such a product is an argument against anyone having such power. -- From: am...@westin-emission.no To: emc-p...@majordomo.ieee.org Subject: Company close down due to EMC phenomena Date: Wed, Jan 16, 2002, 2:17 PM Well, this might be the reality in a case I have been introduced to lately. Case: A company are manufacturing PowerLine Communication products. They communicate via the power lines and a typical link is between a consumer residence and the nearest power station. The products can of course also communicate inside the consumers residence. The communication protocol is called CEBus http://www.cebus.org/which and make use of the frequency band 100kHz-400kHz and the amplitude is approximate 2-5V. A typical length of a transmission is 25ms and occurs approximate one time pr hour. First of all, AFAIK PowerLine Communication and PowerLine Transmission (broadband 1.6MHz-30MHz) are now coming will full force in EU and CENELEC/ETSI are working together regulate this type of transmission path and also coming up with standards. The problem for the manufacturer is the conducted emission requirements in EU. According to the EN55022B levels the maximum quasi-peak emission is 66dBuV@150kHz, and a typical PLC (under transmission) which has been measured, showed the value of 120dBuV (peak). With no transmission it had a margin of 10dB (quasi-peak) and 30dB (average). The radiated emission had a margin of 10dB. Well, conducted emission is the problem when transmitting. But, as I said, the transmission occurs only 25ms/hour. The national authority will not allowed this product to be placed into the marked because it do not fulfil the EN55022B limits (100kHz-400kHz) under transmission mode. No way. Other national authorities have other approaches on this case, they say as long as you do not disturb other equipment, install it. If you do disturb, we will come and remove it. They also say install it even if it does not fulfil EN550022B, but we will remove it if it disturb others. Two completely different approaches as you see. Questions: 1. Is it possible to have different approaches within EU ? 2. Since PLC/PLT is quite new technology and since we do not have any EU product standard (no standard for whose who are using 100kHz-400kHz band), I like the approach as long as you do not disturb other equipment, install it. If you do disturb, we will come and remove it. What is your opinion about this? 3. The transmission occurs very seldom. 25ms/hour, that is 7e-6 and approximate 0,001% transmission rate. Can this seldom transmission rate be an argument to not test the PLC product under continuous transmission ? I would say yes, but which rate is acceptable / reasonable ? So, why should the company close down ? Because if the national authority gets what they want, there will be one sale. Logical, but is it a correct prohibition the authority call? 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
Re: Company close down due to EMC phenomena
A 25 ms burst of noise at a high enough frequency to get out of the radio speaker would sound like a click or pop. A momentary interruption that would be annoying but have no significant impact on information content. -- From: Chris Maxwell chris.maxw...@nettest.com To: am...@westin-emission.no, emc-p...@majordomo.ieee.org Subject: RE: Company close down due to EMC phenomena Date: Thu, Jan 17, 2002, 6:18 AM It sounds as though... The instantaneous emissions aren't as high as an EFT burst or other type of transient phenomenon. So, this product causing a hard upset of electronics is probably not a problem. When the conducted emissions limits were set, they were mostly dealing with whether the product would interfere with radio or TV. As a matter of fact, the quasi-peak and average detectors are used in order to simulate the response of the human ear. I'm curious. If you set this product right next to a radio. Would a human being even be able to perceive the 25millisecond burst? Chris Maxwell | Design Engineer - Optical Division email chris.maxw...@nettest.com | dir +1 315 266 5128 | fax +1 315 797 8024 NetTest | 6 Rhoads Drive, Utica, NY 13502 | USA web www.nettest.com | tel +1 315 797 4449 | -Original Message- From: am...@westin-emission.no [SMTP:am...@westin-emission.no] Sent: Wednesday, January 16, 2002 3:17 PM To: emc-p...@majordomo.ieee.org Subject: Company close down due to EMC phenomena Well, this might be the reality in a case I have been introduced to lately. Case: A company are manufacturing PowerLine Communication products. They communicate via the power lines and a typical link is between a consumer residence and the nearest power station. The products can of course also communicate inside the consumers residence. The communication protocol is called CEBus http://www.cebus.org/which and make use of the frequency band 100kHz-400kHz and the amplitude is approximate 2-5V. A typical length of a transmission is 25ms and occurs approximate one time pr hour. First of all, AFAIK PowerLine Communication and PowerLine Transmission (broadband 1.6MHz-30MHz) are now coming will full force in EU and CENELEC/ETSI are working together regulate this type of transmission path and also coming up with standards. The problem for the manufacturer is the conducted emission requirements in EU. According to the EN55022B levels the maximum quasi-peak emission is 66dBuV@150kHz, and a typical PLC (under transmission) which has been measured, showed the value of 120dBuV (peak). With no transmission it had a margin of 10dB (quasi-peak) and 30dB (average). The radiated emission had a margin of 10dB. Well, conducted emission is the problem when transmitting. But, as I said, the transmission occurs only 25ms/hour. The national authority will not allowed this product to be placed into the marked because it do not fulfil the EN55022B limits (100kHz-400kHz) under transmission mode. No way. Other national authorities have other approaches on this case, they say as long as you do not disturb other equipment, install it. If you do disturb, we will come and remove it. They also say install it even if it does not fulfil EN550022B, but we will remove it if it disturb others. Two completely different approaches as you see. Questions: 1. Is it possible to have different approaches within EU ? 2. Since PLC/PLT is quite new technology and since we do not have any EU product standard (no standard for whose who are using 100kHz-400kHz band), I like the approach as long as you do not disturb other equipment, install it. If you do disturb, we will come and remove it. What is your opinion about this? 3. The transmission occurs very seldom. 25ms/hour, that is 7e-6 and approximate 0,001% transmission rate. Can this seldom transmission rate be an argument to not test the PLC product under continuous transmission ? I would say yes, but which rate is acceptable / reasonable ? So, why should the company close down ? Because if the national authority gets what they want, there will be one sale. Logical, but is it a correct prohibition the authority call? 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
RE: Company close down due to EMC phenomena
touche' (That's too-shay for those not into French, fencing or watching Gilligan's Island reruns) I see your point. I see that you are from a cellular company. What would an entire nation of cellular phones be like? Noisy? Yes, but still functional (sort of like my house). Even though all of the cell phones and their towers have emissions higher than the radiated emissions limits for other products; they transmit in particular bands and use coding and other techniques. Perhaps this is what is wrong with this power line transmission scheme? If they are meant to be commercial products, these devices should be using some sort of standardized/allocated frequency band along with a recognized signaling method. If they were, they wouldn't be up a creek without a paddle; and we wouldn't have this thread. Chris Maxwell | Design Engineer - Optical Division email chris.maxw...@nettest.com | dir +1 315 266 5128 | fax +1 315 797 8024 NetTest | 6 Rhoads Drive, Utica, NY 13502 | USA web www.nettest.com | tel +1 315 797 4449 | -Original Message- From: Sundstrom Michael (NMP-RD/Dallas) [SMTP:michael.sundst...@nokia.com] Sent: Thursday, January 17, 2002 10:39 AM To: Chris Maxwell; am...@westin-emission.no; emc-p...@majordomo.ieee.org Subject: RE: Company close down due to EMC phenomena Guys, I don't think we want to forget that just one of these units will be in use. What would a whole country full of these units do to a mains network? I'd guess it to be very noisy indeed! Michael Sundstrom NOKIA TCC Dallas / EMC ofc: (972) 374-1462 cell: (817) 917-5021 amateur call: KB5UKT -Original Message- From: ext Chris Maxwell [mailto:chris.maxw...@nettest.com] Sent: Thursday, January 17, 2002 6:19 AM To: am...@westin-emission.no; emc-p...@majordomo.ieee.org Subject: RE: Company close down due to EMC phenomena It sounds as though... The instantaneous emissions aren't as high as an EFT burst or other type of transient phenomenon. So, this product causing a hard upset of electronics is probably not a problem. When the conducted emissions limits were set, they were mostly dealing with whether the product would interfere with radio or TV. As a matter of fact, the quasi-peak and average detectors are used in order to simulate the response of the human ear. I'm curious. If you set this product right next to a radio. Would a human being even be able to perceive the 25millisecond burst? Chris Maxwell | Design Engineer - Optical Division email chris.maxw...@nettest.com | dir +1 315 266 5128 | fax +1 315 797 8024 NetTest | 6 Rhoads Drive, Utica, NY 13502 | USA web www.nettest.com | tel +1 315 797 4449 | -Original Message- From: am...@westin-emission.no [SMTP:am...@westin-emission.no] Sent: Wednesday, January 16, 2002 3:17 PM To: emc-p...@majordomo.ieee.org Subject:Company close down due to EMC phenomena Well, this might be the reality in a case I have been introduced to lately. Case: A company are manufacturing PowerLine Communication products. They communicate via the power lines and a typical link is between a consumer residence and the nearest power station. The products can of course also communicate inside the consumers residence. The communication protocol is called CEBus http://www.cebus.org/which and make use of the frequency band 100kHz-400kHz and the amplitude is approximate 2-5V. A typical length of a transmission is 25ms and occurs approximate one time pr hour. First of all, AFAIK PowerLine Communication and PowerLine Transmission (broadband 1.6MHz-30MHz) are now coming will full force in EU and CENELEC/ETSI are working together regulate this type of transmission path and also coming up with standards. The problem for the manufacturer is the conducted emission requirements in EU. According to the EN55022B levels the maximum quasi-peak emission is 66dBuV@150kHz, and a typical PLC (under transmission) which has been measured, showed the value of 120dBuV (peak). With no transmission it had a margin of 10dB (quasi-peak) and 30dB (average). The radiated emission had a margin of 10dB. Well, conducted emission is the problem when transmitting. But, as I said, the transmission occurs only 25ms/hour. The national authority will not allowed this product to be placed into the marked because it do not fulfil the EN55022B limits (100kHz-400kHz) under transmission mode. No way. Other national authorities have other approaches on this case, they say as long as you do not disturb other equipment, install it. If you do disturb, we will come and remove it. They also say install it even if it does not fulfil EN550022B, but we will remove it if it disturb others. Two completely different approaches as you see. Questions: 1. Is it possible to have
RE: Company close down due to EMC phenomena
Guys, I don't think we want to forget that just one of these units will be in use. What would a whole country full of these units do to a mains network? I'd guess it to be very noisy indeed! Michael Sundstrom NOKIA TCC Dallas / EMC ofc: (972) 374-1462 cell: (817) 917-5021 amateur call: KB5UKT -Original Message- From: ext Chris Maxwell [mailto:chris.maxw...@nettest.com] Sent: Thursday, January 17, 2002 6:19 AM To: am...@westin-emission.no; emc-p...@majordomo.ieee.org Subject: RE: Company close down due to EMC phenomena It sounds as though... The instantaneous emissions aren't as high as an EFT burst or other type of transient phenomenon. So, this product causing a hard upset of electronics is probably not a problem. When the conducted emissions limits were set, they were mostly dealing with whether the product would interfere with radio or TV. As a matter of fact, the quasi-peak and average detectors are used in order to simulate the response of the human ear. I'm curious. If you set this product right next to a radio. Would a human being even be able to perceive the 25millisecond burst? Chris Maxwell | Design Engineer - Optical Division email chris.maxw...@nettest.com | dir +1 315 266 5128 | fax +1 315 797 8024 NetTest | 6 Rhoads Drive, Utica, NY 13502 | USA web www.nettest.com | tel +1 315 797 4449 | -Original Message- From: am...@westin-emission.no [SMTP:am...@westin-emission.no] Sent: Wednesday, January 16, 2002 3:17 PM To: emc-p...@majordomo.ieee.org Subject: Company close down due to EMC phenomena Well, this might be the reality in a case I have been introduced to lately. Case: A company are manufacturing PowerLine Communication products. They communicate via the power lines and a typical link is between a consumer residence and the nearest power station. The products can of course also communicate inside the consumers residence. The communication protocol is called CEBus http://www.cebus.org/which and make use of the frequency band 100kHz-400kHz and the amplitude is approximate 2-5V. A typical length of a transmission is 25ms and occurs approximate one time pr hour. First of all, AFAIK PowerLine Communication and PowerLine Transmission (broadband 1.6MHz-30MHz) are now coming will full force in EU and CENELEC/ETSI are working together regulate this type of transmission path and also coming up with standards. The problem for the manufacturer is the conducted emission requirements in EU. According to the EN55022B levels the maximum quasi-peak emission is 66dBuV@150kHz, and a typical PLC (under transmission) which has been measured, showed the value of 120dBuV (peak). With no transmission it had a margin of 10dB (quasi-peak) and 30dB (average). The radiated emission had a margin of 10dB. Well, conducted emission is the problem when transmitting. But, as I said, the transmission occurs only 25ms/hour. The national authority will not allowed this product to be placed into the marked because it do not fulfil the EN55022B limits (100kHz-400kHz) under transmission mode. No way. Other national authorities have other approaches on this case, they say as long as you do not disturb other equipment, install it. If you do disturb, we will come and remove it. They also say install it even if it does not fulfil EN550022B, but we will remove it if it disturb others. Two completely different approaches as you see. Questions: 1. Is it possible to have different approaches within EU ? 2. Since PLC/PLT is quite new technology and since we do not have any EU product standard (no standard for whose who are using 100kHz-400kHz band), I like the approach as long as you do not disturb other equipment, install it. If you do disturb, we will come and remove it. What is your opinion about this? 3. The transmission occurs very seldom. 25ms/hour, that is 7e-6 and approximate 0,001% transmission rate. Can this seldom transmission rate be an argument to not test the PLC product under continuous transmission ? I would say yes, but which rate is acceptable / reasonable ? So, why should the company close down ? Because if the national authority gets what they want, there will be one sale. Logical, but is it a correct prohibition the authority call? 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
RE: Company close down due to EMC phenomena
It sounds as though... The instantaneous emissions aren't as high as an EFT burst or other type of transient phenomenon. So, this product causing a hard upset of electronics is probably not a problem. When the conducted emissions limits were set, they were mostly dealing with whether the product would interfere with radio or TV. As a matter of fact, the quasi-peak and average detectors are used in order to simulate the response of the human ear. I'm curious. If you set this product right next to a radio. Would a human being even be able to perceive the 25millisecond burst? Chris Maxwell | Design Engineer - Optical Division email chris.maxw...@nettest.com | dir +1 315 266 5128 | fax +1 315 797 8024 NetTest | 6 Rhoads Drive, Utica, NY 13502 | USA web www.nettest.com | tel +1 315 797 4449 | -Original Message- From: am...@westin-emission.no [SMTP:am...@westin-emission.no] Sent: Wednesday, January 16, 2002 3:17 PM To: emc-p...@majordomo.ieee.org Subject: Company close down due to EMC phenomena Well, this might be the reality in a case I have been introduced to lately. Case: A company are manufacturing PowerLine Communication products. They communicate via the power lines and a typical link is between a consumer residence and the nearest power station. The products can of course also communicate inside the consumers residence. The communication protocol is called CEBus http://www.cebus.org/which and make use of the frequency band 100kHz-400kHz and the amplitude is approximate 2-5V. A typical length of a transmission is 25ms and occurs approximate one time pr hour. First of all, AFAIK PowerLine Communication and PowerLine Transmission (broadband 1.6MHz-30MHz) are now coming will full force in EU and CENELEC/ETSI are working together regulate this type of transmission path and also coming up with standards. The problem for the manufacturer is the conducted emission requirements in EU. According to the EN55022B levels the maximum quasi-peak emission is 66dBuV@150kHz, and a typical PLC (under transmission) which has been measured, showed the value of 120dBuV (peak). With no transmission it had a margin of 10dB (quasi-peak) and 30dB (average). The radiated emission had a margin of 10dB. Well, conducted emission is the problem when transmitting. But, as I said, the transmission occurs only 25ms/hour. The national authority will not allowed this product to be placed into the marked because it do not fulfil the EN55022B limits (100kHz-400kHz) under transmission mode. No way. Other national authorities have other approaches on this case, they say as long as you do not disturb other equipment, install it. If you do disturb, we will come and remove it. They also say install it even if it does not fulfil EN550022B, but we will remove it if it disturb others. Two completely different approaches as you see. Questions: 1. Is it possible to have different approaches within EU ? 2. Since PLC/PLT is quite new technology and since we do not have any EU product standard (no standard for whose who are using 100kHz-400kHz band), I like the approach as long as you do not disturb other equipment, install it. If you do disturb, we will come and remove it. What is your opinion about this? 3. The transmission occurs very seldom. 25ms/hour, that is 7e-6 and approximate 0,001% transmission rate. Can this seldom transmission rate be an argument to not test the PLC product under continuous transmission ? I would say yes, but which rate is acceptable / reasonable ? So, why should the company close down ? Because if the national authority gets what they want, there will be one sale. Logical, but is it a correct prohibition the authority call? 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
Re: Company close down due to EMC phenomena
Close down? That's alarming. And probably not what needs to happen. Power Line communication is controversial at the moment, especially with trials underway in the Netherlands and some deployments in Germany which generated high levels of RFI. (And appear to have been exceedingly vulnerable to radio signals as well). I understand that the only way the Germans could begin deployment was to enact a standard that allows much higher emissions, NB30. In the UK, MPT1570 is under study. However, it looks as if radiated field strength will not be acceptably low for residential radio receivers. This might not be the case with CEBus. There IS a CEBus hardware standard, EIA 600.31. However, CEBus doesn't look designed with European spectrum use in mind. It would be less an issue in the USA, where FCC conducted emission limits start (for now - we have yet to harmonize with Europe) at 450 KHz. If your user can keep emissions below 150 Khz, it should not be a problem in Europe, either. Why not do that? Alternatively, the peak level need not be a problem if quasi-peak measurements can be kept below the limit. This would depend on the sweep rate used by the signal. You don't need to close down. Just follow the rules where you sell equipment. Some authorities may interpret rules more strictly than others. For a long time that was Germany. Remember? We all tried to meet VDE 0871 because everyone accepted it. Well, now you have differing opinions. Isn't it true that if you get a NB to sign off on the TCF or DoC, it's approved all over Europe? I'd not rely on that 25 ms per hour to gain permission, though. Would I be allowed to operate a radio transmitter 60 dB above authorized levels if I only did it 25 ms per hour? Not even then! And do note that not all CEBus signals have the short duty cycle your application does. Cheers, Cortland (The people that I work for, Don't tell me what to say; I don't speak for them, ever, And we both like things that way.) am...@westin-emission.no wrote: Well, this might be the reality in a case I have been introduced to lately. Case: A company are manufacturing PowerLine Communication products. They communicate via the power lines and a typical link is between a consumer residence and the nearest power station. The products can of course also communicate inside the consumers residence. The communication protocol is called CEBus http://www.cebus.org/which and make use of the frequency band 100kHz-400kHz and the amplitude is approximate 2-5V. A typical length of a transmission is 25ms and occurs approximate one time pr hour. First of all, AFAIK PowerLine Communication and PowerLine Transmission (broadband 1.6MHz-30MHz) are now coming will full force in EU and CENELEC/ETSI are working together regulate this type of transmission path and also coming up with standards. The problem for the manufacturer is the conducted emission requirements in EU. According to the EN55022B levels the maximum quasi-peak emission is 66dBuV@150kHz, and a typical PLC (under transmission) which has been measured, showed the value of 120dBuV (peak). With no transmission it had a margin of 10dB (quasi-peak) and 30dB (average). The radiated emission had a margin of 10dB. Well, conducted emission is the problem when transmitting. But, as I said, the transmission occurs only 25ms/hour. The national authority will not allowed this product to be placed into the marked because it do not fulfil the EN55022B limits (100kHz-400kHz) under transmission mode. No way. Other national authorities have other approaches on this case, they say as long as you do not disturb other equipment, install it. If you do disturb, we will come and remove it. They also say install it even if it does not fulfil EN550022B, but we will remove it if it disturb others. Two completely different approaches as you see. Questions: 1. Is it possible to have different approaches within EU ? 2. Since PLC/PLT is quite new technology and since we do not have any EU product standard (no standard for whose who are using 100kHz-400kHz band), I like the approach as long as you do not disturb other equipment, install it. If you do disturb, we will come and remove it. What is your opinion about this? 3. The transmission occurs very seldom. 25ms/hour, that is 7e-6 and approximate 0,001% transmission rate. Can this seldom transmission rate be an argument to not test the PLC product under continuous transmission ? I would say yes, but which rate is acceptable / reasonable ? So, why should the company close down ? Because if the national authority gets what they want, there will be one sale. Logical, but is it a correct prohibition the authority call? 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:
Re: Company close down due to EMC phenomena
I read in !emc-pstc that am...@westin-emission.no wrote (in LFENJLPMMJB mhpeibnilcedfccaa.am...@westin-emission.no) about 'Company close down due to EMC phenomena', on Wed, 16 Jan 2002: Questions: 1. Is it possible to have different approaches within EU ? No. 2. Since PLC/PLT is quite new technology and since we do not have any EU product standard (no standard for whose who are using 100kHz-400kHz band), I like the approach as long as you do not disturb other equipment, install it. If you do disturb, we will come and remove it. What is your opinion about this? The problem is that the technology has run far ahead of the standardization, in this case, simply because it is a very complex technical problem, not because it's been ignored. 3. The transmission occurs very seldom. 25ms/hour, that is 7e-6 and approximate 0,001% transmission rate. Can this seldom transmission rate be an argument to not test the PLC product under continuous transmission ? I would say yes, but which rate is acceptable / reasonable ? I don't think ad hoc solutions like that are appropriate. A proper resolution of the fundamental problem is essential. So, why should the company close down ? Because if the national authority gets what they want, there will be one sale. Logical, but is it a correct prohibition the authority call? No, it is an unduly harsh interpretation. The following IEC standard may be helpful: Project : IEC 61000-4-13 Ed. 1.0 Committee 77A Current document 77A/368/FDIS Current status CDIS - Draft circulated as FDIS Title (English): Electromagnetic Compatibility (EMC) - Part 4-13: Testing and measurement techniques - Harmonics and interharmonics including mains signalling at a.c. power port, low frequency immunity tests - Basic EMC Publication -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk After swimming across the Hellespont, I felt like a Hero. --- 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: Company close down due to EMC phenomena
Hello , I think we are missing the point here. CISPR 22 is an emission standard not an RF standard. CISPR 22 limits do not apply to the intentional radio frequencies. As this is an intentional radiator the product falls under the RTTE directive. That will also mean that notification must be given. If a particular country refuses your product then they must provide written reasons to Brussels. I think they would have a problem denying a radio access to their market based on it's transmit frequency exceeding the permitted power level for emissions in CISPR 22 :) How about another argument on a completely different tack? If one uses CISPR 22 then I noticed you quoted a peak measurement for the transmission. Assuming this is not a typo then the measurement is taken incorrectly. Pressing peak hold on a SA doesn't cut it for this measurement. It must be quasi peak and average measurements. If one ignores the problem of even capturing the transmission properly, then consider the following. As CE bus transmissions :jitter over a wide band you may pass when you consider the settling time of the detectors, the measurement bandwidth and the apparent bandwidth of the transmission and the shortness of your transmission. Best Regards, Kevin Harris Manager, Approval Services Digital Security Controls 3301 Langstaff Road Concord, Ontario CANADA L4K 4L2 Tel: +1 905 760 3000 Ext. 2378 Fax +1 905 760 3020 Email: harr...@dscltd.com -Original Message- From: Ken Javor [mailto:ken.ja...@emccompliance.com] Sent: Wednesday, January 16, 2002 4:53 PM To: am...@westin-emission.no; emc-p...@majordomo.ieee.org Subject:Re: Company close down due to EMC phenomena A technical response from an American. I sympathize with the viewpoint that the duty cycle is very low and the on-time is very low and the potential for mischief is near nil. I would add a further argument. 55022 CE limits protect AM radio reception. In the USA there is no AM broadcast below 530 kHz. In the EU there is some LW broadcasting from I believe 150 - 300 kHz, and then MW picks up again at 530 kHz. So the potential for rfi is limited. That officials would even consider banning such a product is an argument against anyone having such power. -- From: am...@westin-emission.no To: emc-p...@majordomo.ieee.org Subject: Company close down due to EMC phenomena Date: Wed, Jan 16, 2002, 2:17 PM Well, this might be the reality in a case I have been introduced to lately. Case: A company are manufacturing PowerLine Communication products. They communicate via the power lines and a typical link is between a consumer residence and the nearest power station. The products can of course also communicate inside the consumers residence. The communication protocol is called CEBus http://www.cebus.org/which and make use of the frequency band 100kHz-400kHz and the amplitude is approximate 2-5V. A typical length of a transmission is 25ms and occurs approximate one time pr hour. First of all, AFAIK PowerLine Communication and PowerLine Transmission (broadband 1.6MHz-30MHz) are now coming will full force in EU and CENELEC/ETSI are working together regulate this type of transmission path and also coming up with standards. The problem for the manufacturer is the conducted emission requirements in EU. According to the EN55022B levels the maximum quasi-peak emission is 66dBuV@150kHz, and a typical PLC (under transmission) which has been measured, showed the value of 120dBuV (peak). With no transmission it had a margin of 10dB (quasi-peak) and 30dB (average). The radiated emission had a margin of 10dB. Well, conducted emission is the problem when transmitting. But, as I said, the transmission occurs only 25ms/hour. The national authority will not allowed this product to be placed into the marked because it do not fulfil the EN55022B limits (100kHz-400kHz) under transmission mode. No way. Other national authorities have other approaches on this case, they say as long as you do not disturb other equipment, install it. If you do disturb, we will come and remove it. They also say install it even if it does not fulfil EN550022B, but we will remove it if it disturb others. Two completely different approaches as you see. Questions: 1. Is it possible to have different approaches within EU ? 2. Since PLC/PLT is quite new technology and since we do not have any EU product standard (no standard for whose who are using 100kHz-400kHz band), I like the approach as long as you do not disturb other equipment, install it. If you do disturb, we will come and remove it. What is your opinion about this? 3. The transmission occurs very seldom. 25ms/hour, that is 7e-6 and approximate 0,001% transmission rate. Can this seldom transmission rate be an argument to not test the PLC product under continuous transmission ? I would say yes, but which rate is acceptable / reasonable ? So, why should the company close
Re: Company close down due to EMC phenomena
Hi Amund: I suggest you and your client and the regulatory authority meet to address the situation. Here are the issues as I understand them from your message: 1. In idle mode, the emissions are comfortably below the maximum allowed emissions. 2. In transmit mode, the emissions exceed the maximum allowed emissions. The duration of the transmission is 25 ms. The repetition rate of the transmission is about 1/hour. 3. The emission level is probably related to the nature of the system, i.e., transmission via the power distribution network. I feel that 25 ms/hour is the important parameter. I suspect that most motor-starting events exceed the emission level, and for more than 25 ms. Like- wise, I suspect most igniter events also exceed the emission level and for more than 25 ms. Does your regulatory authority permit such emissions? Set up the system for normal operation. Ask the regulatory authority to measure the emissions. The emissions will be in compliance for 1 hour. The regulatory authority must be observing the emissions at the moment of the 25 ms transmission in order to determine if the emissions exceed the allowed level. I suspect this is a difficult measurement. The receiver or SA must be tuned to the transmit frequency during the 25 ms transmit interval. This probably requires advance knowledge of the transmit frequency, and therefore the measurment is not an agnostic measurement. (If you were submitting the equipment to the regulatory authority, do you have an obligation to inform them of expected performance of the unit, especially the specifics of the transmit mode?) And, there must be some means of capturing the data during the event. Short of staring at the SA screen for an hour or more, I'm not sure this can be done except with exceptional effort and additional equipment. The preceding paragraph is something of a game to play with the regulatory authority. So, why should the company close down ? Because if the national authority gets what they want, there will be one sale. Logical, but is it a correct prohibition the authority call? The company SHOULD have known that its product would exceed conducted emissions. The company SHOULD have taken appropriate steps with the regulatory authority to know whether or not its product would be approved BEFORE it invested in the product development. This is not a fault of the regulatory authority, but a fault of the company to not understand the regulations BEFORE it developed the product. Best regards, Rich --- 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: Company close down due to EMC phenomena
A technical response from an American. I sympathize with the viewpoint that the duty cycle is very low and the on-time is very low and the potential for mischief is near nil. I would add a further argument. 55022 CE limits protect AM radio reception. In the USA there is no AM broadcast below 530 kHz. In the EU there is some LW broadcasting from I believe 150 - 300 kHz, and then MW picks up again at 530 kHz. So the potential for rfi is limited. That officials would even consider banning such a product is an argument against anyone having such power. -- From: am...@westin-emission.no To: emc-p...@majordomo.ieee.org Subject: Company close down due to EMC phenomena Date: Wed, Jan 16, 2002, 2:17 PM Well, this might be the reality in a case I have been introduced to lately. Case: A company are manufacturing PowerLine Communication products. They communicate via the power lines and a typical link is between a consumer residence and the nearest power station. The products can of course also communicate inside the consumers residence. The communication protocol is called CEBus http://www.cebus.org/which and make use of the frequency band 100kHz-400kHz and the amplitude is approximate 2-5V. A typical length of a transmission is 25ms and occurs approximate one time pr hour. First of all, AFAIK PowerLine Communication and PowerLine Transmission (broadband 1.6MHz-30MHz) are now coming will full force in EU and CENELEC/ETSI are working together regulate this type of transmission path and also coming up with standards. The problem for the manufacturer is the conducted emission requirements in EU. According to the EN55022B levels the maximum quasi-peak emission is 66dBuV@150kHz, and a typical PLC (under transmission) which has been measured, showed the value of 120dBuV (peak). With no transmission it had a margin of 10dB (quasi-peak) and 30dB (average). The radiated emission had a margin of 10dB. Well, conducted emission is the problem when transmitting. But, as I said, the transmission occurs only 25ms/hour. The national authority will not allowed this product to be placed into the marked because it do not fulfil the EN55022B limits (100kHz-400kHz) under transmission mode. No way. Other national authorities have other approaches on this case, they say as long as you do not disturb other equipment, install it. If you do disturb, we will come and remove it. They also say install it even if it does not fulfil EN550022B, but we will remove it if it disturb others. Two completely different approaches as you see. Questions: 1. Is it possible to have different approaches within EU ? 2. Since PLC/PLT is quite new technology and since we do not have any EU product standard (no standard for whose who are using 100kHz-400kHz band), I like the approach as long as you do not disturb other equipment, install it. If you do disturb, we will come and remove it. What is your opinion about this? 3. The transmission occurs very seldom. 25ms/hour, that is 7e-6 and approximate 0,001% transmission rate. Can this seldom transmission rate be an argument to not test the PLC product under continuous transmission ? I would say yes, but which rate is acceptable / reasonable ? So, why should the company close down ? Because if the national authority gets what they want, there will be one sale. Logical, but is it a correct prohibition the authority call? 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 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
