Deluge after Frankfurt
By J. M. Woodgate B.Sc.(Eng.) C.Eng. MIET MIEEE FAES
There has been a huge burst of circulated standards documents since last time, partly because of the CISPR meetings in Frankfurt in October.
CISPR, as the policy committee, has two 'political' matters to deal with at present. CISPR, as advised by its Steering Committee, CISPR/S, can make policy decisions on the content of standards and other matters, but the IEC rules allow CISPR sub-committees to derogate from those decisions and it's far from obvious how the rules could be changed to remove the anomaly. Of course, the sub-committees could be re-designated as Working Groups...
A new Document for Comment (DC) will be circulated, giving the proposed new CISPR rule, which will be published, when approved, in an INF document until the ISO/IEC Directive Part 1 (or the IEC Supplement) is revised.
The other problematic issue is the 80/80 rule, which in Europe is now considered regulatory and thus should not appear in standards. CISPR decided to tell the European Commission that it isn't regulatory. More on this in the Column, because strictly it's not about standards.
A third issue was 'kicked upstairs' to ACEC – a system committee proposed to produce rather stringent EMC standards for some products, which hasn't gone down too well with the product committees concerned. IEC Guide 107 makes it clear that CISPR and TC77 limits shall be applied by all other committees (unless there is a VERY good case made out for deviation).
This extremely active committee on EMC methods of measurement continues to produce many documents relating to the huge 4-Part CISPR 16. There remain obscurities and inconsistencies despite the work done over the last three years to eliminate them.
A particular concern is an attempt, originated by British experts, to improve the texts on site acceptance in CISPR 16-1-4. The subject is technically quite complex; traditional methods of measurement are now considered less than satisfactory, and the upper frequency bound has moved from 1 GHz to 18 GHz. In addition, the texts on uncertainty budgets do not reflect the performance of modern test equipment. There are also issues concerning the movement of antennas during some procedures.
The proposals have proved very controversial, partly because there are fears, somewhat justified, that existing test facilities, some not so very old, might not meet newly-proposed criteria. It seems that the project will not go ahead in its present form. The subject has actually generated two new Sections of CISPR-16-1, Sections 5 and 6, both of which have passed their FDIS vote.
A document CISPR/A/1092/INF concerning SC A/SC H JTF on reverberation chambers was due to be discussed in SC A WG1 but appears not to have been reviewed.
The chairman of CISPR/B is to retire a year early to allow a new chairman to act at the next Plenary meeting in September 2015. The five fragment CDVs for the revision of CISPR 11 have all passed their vote. Unusually, a draft combined FDIS for the 6th Edition was circulated first as an INF document, and the final version is expected to be circulated early in 2015. However, already Amendment 1 to the new standard is planned, with at least two fragments. Fragment 1, on measurements at 3 m separation has been set to Stage Zero, to give time for CISPR A to study basic principles. Fragment 2, on the use of fully anechoic rooms (FAR), will proceed to a 3CD or CDV.
CISPR B is also studying wireless power transfer, and this is also of interest to many other committees. There is an existing ETSI standard, EN 300 330-1, which CISPR I wants to adapt for CISPR 32. CISPR 18 and CISPR TR26 are under maintenance, but progress is slow.
This committee has three main tasks – the maintenance of CISPR 12 and 25 and work on a new standard, CISPR 36. The maintenance of CISPR 12 is at the 1CD stage, but that for CISPR 25 is at the 3CD stage, indicating some on-going controversy. It is a very long document – 152 pages – so there is ample opportunity for comments. The comments on this document were available at the meeting but have not yet been circulated. The project team for CISPR 36 Vehicles, boats and internal combustion engines - Radio disturbance characteristics - Limits and methods of measurements of radiated field below 30 MHz expect a 1CD after June 2015. The document considers only magnetic fields and only in the range above 150 kHz.
The combined CD (editorial and technical) for the revision of CISPR 14-1 has received a 'warm' reception – 33 pages of National Committee comments, which were discussed in Frankfurt. While there are quite a few technical comments, there are very many editorial comments, many of which really should not have escaped into a circulated document. It is possible that the next stage will be a CDV. The RMS-average detector will not be included.
The revision of CISPR 14-2 has fared better. The CDV was voted positively and the FDIS is being processed. The same applies to three amendments to CISPR 15 Ed. 8, all voted through at the CDV stage. The subsequent full revision, to make Ed. 9, is also under way and involves a lot of intricate work; the next stage may be a second DC or an RR and a CD. A notable innovation is port-based testing, necessary because so many lighting products have digital control and communication facilities.
No changes are envisaged for CISPR TR 30-1 and 30-2. The proposed TR30-3 on LED reference luminaires will not now be progressed. The necessary texts will be added to CISPR 15 Ed. 9.
CISPR/F has a considerable interest in the EMC characteristics of grid-controlled power converters (GCPC) and DC networks for lighting. CISPR/H is developing models, from which emission limits can be developed. Concern has been expressed at the addition by CISPR H of general DC networks to the original work on GCPC.
Three SC H projects have experienced delays. Amendment 1 to CISPR 16-4-4 was delayed due to a need for technical verification of provisions in the 3CD. This amendment is concerned with protection limits for radiated (magnetic) disturbances in the frequency range 9 kHz to 30 MHz. It seems a problematical task, because the sensitivity of common objects to low(ish) frequency magnetic fields varies from very high (electric guitars) to very low (simple jug kettles).
IEC 61000-6-3 amendment 2 and IEC 61000-6-4 amendment 2 were delayed due to technical questions about alternative test methods. These Generic standards are being changed quite a lot, so users may need to study the implications.
CISPR/H will make a new study of emission limits in the range 9 kHz to 150 kHz, but wait for further information before proposing limits. CISPR 31, the database of characteristics of radio services, is to be reconstituted, after consulting National Committees.
Perhaps the most pressing question for CISPR/I is the future of CISPR 35, which has proved very controversial and has taken a very long time to develop. Because of the latter, it had to go through the New Work procedure again, with a draft containing only the texts that were considered non-controversial. The closing date for voting was 3 October 2014, and it was reported to CISPR/I that the document was approved by a large majority. However, at the time of writing, the voting report has not been circulated. A CDV is planned for March 2015.
Another issue for CISPR 35 is the coexistence of broadcast and mobile radio in the VHF and UHF bands. A questionnaire resulted in an example of the rather too-common inconsistent response from National Committees. 19 voted to include this topic in CISPR 35 and 12 considered that an addition to the standard is required, but opinion was equally divided on whether CISPR/I should start the work! It is probably necessary not to have too many questions and to word the questions very carefully so as to try to avoid inconsistent responses. Not easy!
To add to CISPR/I's troubles (probably) CENELEC have put up for adoption EN 50561-1:2013 Power line communication apparatus used in low-voltage installations. Radio disturbance characteristics. Limits and methods of measurement. Apparatus for in-home use
A Questionnaire has been circulated, with a single question - to circulate the CENELEC document as a CDV or not. There may be a chance that this standard is acceptable in enough countries to allow it to fly, but it does not seem a good chance.
While CISPR has been meeting, other EMC committees have continued to emit. TC 77 circulated the voting report on the FDIS for IEC 6100-6-7, the National Committee comments on the CD for the revision of IEC 61000-1-2 and the voting report on the CDV for IEC 61000-6-5.
A series of documents has been circulated on the maintenance of IEC 61000-3-2. DON’T PANIC! Nothing revolutionary is planned. A DC was issued and the report of National Committee comments has been circulated. Ten sets of comments were submitted, some extensive but none seem highly controversial. National Committees are invited to resubmit their comments at the CD stage, as some reported that they preferred to do this. But this rather defeats the purpose of circulating the DC.
The current 4th Edition is to be revised and made into a 5th Edition by means of four fragments, on lighting equipment, test conditions for TV sets and induction cooking appliances and a full editorial revision to bring the standard into agreement with ISO/IEC Directives Part 2. These will be combined at the FDIS stage.
The FDIS for IEC 61000-4-30 on power quality measurement methods has been circulated.
This committee has circulated National Committee comments on a CD for IEC 61000-4-9 (document 77B/720/CC – the IEC web page is a bit garbled) and a new CD (50 pages) for the standard. There is also a new CD for IEC 61000-4-10 and a Review Report (RR) for the preparation of a second edition.
What of the future?
As is often the case, it is difficult to predict, but there does not seem to be anything controversial being cooked up. The next offering will have to be submitted before EMC committee meetings planned for early next year take place.