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: 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.
