Scott, I am not familiar with the standard you cite, but am quite familiar with BCI testing in general and the equipment used specifically. The injection clamp used to 400 MHz is only good to 400 or 450 MHz, depending upon manufacturer. The current probe used to monitor CUT-injected current will either be good to 450 MHz or 1 GHz. To my knowledge, there are no current probes in general use above 1 GHz and measurement of current on an unmatched transmission line (the CUT) becomes quite problematical even at 400 MHz. So my answer, not authoritative in a specification sense, but based on the physics of the situation and the test equipment available is that you control harmonics up to 400 MHz, and don't try to measure beyond that.
P.S. You should have no such problems regardless. The harmonic problem is an issue when you are at the very low end of the frequency range of an injection clamp and it is more efficient at the harmonics than at the fundamental. The high power tube amps used up to 220 MHz do have high harmonic content (-16 dBc), but you should be able to use a lower power solid-state amp with better performance, and in any case you have an easy out. There is a clamp that covers 0.01 - 100 MHz and another that covers 2 - 400 MHz. If you use the lower range clamp to 10 MHz or thereabouts you can start using the upper range clamp at a frequency where its insertion loss is flat with frequency. The lower range clamp is flat from below 1 MHz and on up. Ken on 1/9/02 2:41 PM, scott....@jci.com at scott....@jci.com wrote: > > To All, > > We are performing BCI testing according to the test method described in ISO > 11452-4 (Test Range 1MHz - 400MHz) > > We are unclear on the statement described in Section 3 - "Test Conditions" > regarding measuring the harmonics. > The standard indicates that if a deviation in product performance occurs, > the first 5 harmonics (relative to the carrier) must be measured. These > harmonics must not exceed -9dBc. > > Here's where my question originates... The standard says "...it must be > ensured that any of the first five harmonics (up to 400MHz) shall not > exceed - 9dBc relative to the fundamental frequency....." > > > I am looking for help with interpreting the text in the specification. > > > 1. Does the text indicate that only harmonics with frequencies from 1 - > 400MHz should be considered (carrier frequencies less than 80MHz)? > > 2. Does the text indicate that harmonics up to 2GHz (400MHz is the highest > test frequency - multiplied by 5 harmonics = 2GHz) SHOULD BE MEASURED.? > > 3. other? > > Any help would be greatly appreciated. > > Thank you. > > > Regards, > > Scott Mee > EMC Engineer > > Johnson Controls Inc. > PH: 616.394.2565 > EMAIL: scott....@jci.com > > > ------------------------------------------- > 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.
