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The UK's premier EMC consultancyElmac Services offer design consultancy and training on EMC aspects at all stages of electronic and electrical product development. This includes individual consultancy and training seminars to your own requirements. We have particular expertise in the application of European EMC standards and test methods.Many companies do not have the resources to be expert in EMC and need the services of an EMC consultant. We can help you with
Elmac Services have extensive experience in product design to both immunity and emission standards. We number a wide variety of electrical and electronics companies among our clients, from the smallest to the largest. If you have EMC problems, we'll help you solve them.
Training
Tim Williams will also be in India in November 2010 for the 11th International Conference on Electromagnetic Interference & Compatibility - (INCEMIC 2010). In Bangalore on 23rd-26th November, it features two days of workshops where Tim will be running a day on Developments in EMC Testing. Meanwhile, if you want your own EMC seminar, get in touch for an in-house training course - our training page lists a whole menu of topics that can be covered, all you need to do is choose. NB we have just added a new one-day module on the EMC Design Review and how to do it. Power Line Telecommunication
At the beginning of September 2009 Ofcom came to a "decision" about PLT, which can be found on their website. Interested parties are encouraged to review this statement. The notable point is that "On the evidence, Ofcom has not so far found that there is a breach of the EMC essential requirements. Ofcom has therefore decided against taking further enforcement action at this time." This despite an acknowledged number of 143 complaints against PLT apparatus (at that time, now over 200); and in the next breath, the statement "It is recognised that EMC compliant equipment may still, in certain circumstances, have the capacity to cause interference to other radio communications equipment. This may happen due to the manner in which it is installed or operated." In the case of PLT in-home adaptors, this means plugging them in and switching them on. Ofcom commissioned a report on PLT from PA Consulting; it was originally due for publication in November 2009, but has not yet appeared.
Tim Williams has now written three articles on the subject in the
EMC Journal (in January, May and July 2009, the last issue having several PLT papers including from Keith Armstrong and Richard Marshall) and these have been added to this site, see the Papers page for downloads. Also on the same page you will find some sample
audio files of the interference generated by the Comtrend adaptors supplied with BT Vision.
Meanwhile, the CISPR/I PLT project team, who were attempting to find a way to publish an amendment to CISPR 22 which would have applied to PLT modems, have been told to start again. This means that there will not be any such amendment in the next few years. "There is clearly no consensus in the CISPR I National committees for the circulation of a CDV, and any CDV circulated would be expected to fail." The document that was under consideration would have legitimized high levels of emissions on the basis of a technical fix involving dynamic notching and/or power management; see the articles cited above for a view on this. At the same time, a proposal in CISPR/H to develop radiated limits below 30MHz within CISPR 16-4-4, which would have applied to the interference potential of wire line fixed installations carrying broadband communications, has failed for the near term. It may be resurrected in a couple of years' time, but for now CISPR/H has failed to grasp this particular nettle.
The Digital Dividend
Got here by mistake?Not interested in EMC? Looking for a different Elmac? Try this one for flame arrestors; or this one for graffiti art; or this one for Italian gaming machines. |
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Contact: |
Elmac Services, Wareham, Dorset - Phone +44 (0)1929 558279 |