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 Heald davehe...@mediaone.net > > For policy questions, send mail to: > Richard Nute: ri...@ieee.org > Jim Bacher: j.bac...@ieee.org > > All emc-pstc postings are archived and searchable on the web at: > No longer online until our new server is brought online and the old > messages are imported into the new server. > ------------------------------------------- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson: pstc_ad...@garretson.org Dave Heald davehe...@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.
