Ed: I use toroidal cores on anmost everything and they work by reducing the conducted common mode RF on the poweline to the equipment, the cable to VCrs or TVs or telephones ext. Toroid cores are nonn intrusive, void no warranties, do not compromise safety and may be removed an retruned to the owner when they're no longer needed. They are the perfect after sale for improving conducted immunity of electronic equipment.
So to answer your quesrion, I'm talking about preventing the energy from entering the conducted port of the victim equipment. How we define sonducted port may differ from the common notion that the energytravels on the sheath of coax cable and if its not inhibited in some way it gets onto chassis ground and then its too late. I use the term isolate the DUT from the energy but do it with passive means. BTW if we all understand that acronym, I've been using the same technique successfully in most cases ( >95%) for 25 years. Its an ideal after sale solution which has been ignored. Ralph ----- Original Message ----- From: "Price, Ed" <ed.pr...@cubic.com> To: "EMC-PSTC (E-mail)" <emc-p...@ieee.org> Sent: Tuesday, June 26, 2001 8:20 PM Subject: RE: Examples of EMC problems in the real world > > >-----Original Message----- > >From: Gary McInturff [mailto:gary.mcintu...@worldwidepackets.com] > >Sent: Wednesday, June 20, 2001 2:12 PM > >To: EMC-PSTC (E-mail) > >Subject: Examples of EMC problems in the real world > > > > > > > > There have been requests in the past on this forum for > >examples of > >real world events that were EMC related, as I recall we got a > >few but not > >many examples. In an email with Ralph he mentioned some work > >and an article > >that he had written chronically some of these problems. I > >asked him for some > >of his examples and he kindly sent the items below and has graciously > >allowed me to forward them. > > Thanks Ralph, and I hope that you enjoy them as much as I did. > > Gary > > > >-----Original Message----- > >From: Ralph Cameron [mailto:ral...@igs.net] > >Sent: Tuesday, June 19, 2001 6:14 PM > >To: Gary McInturff > >Subject: Some life threatening cases of EMI and others > > > > > >Gary: > > > >These cases were reviewed in an article I wrote about 14-15 > >years ago. Most > >incidents could happen tomorrow and came from a record of emi > >cases reported > >to all Canadian district offices of what used to be called > >Communications > >Canada. The reports covered a planned three month monitoring > >period during > >which time ther were 439 emi related reports and another 242 cases of > >swamping > >( RF overload of TV, radio etc.) If you consider that > >Canadian incidents > >represented about 8% of the total number of incidents in the > >U.S. at that > >time, it may help to place the occurrences in perspective. > > > >Since that time, Industry Canada has not recorded domestic problems or > >complaints due to a lack of immunity ( radiated or conducted) > >but do have > >an advisory bulletin specifying field strengths communication > >transmitter > >owners cannot exceed. These limits are taken from the EU > >requirements for > >electronic equipment radiated immunity . Not surprisingly, I > >have found at > >least 95% of interference cases have been resolved not by increasing > >radiated immunity but, by reducing or eliminating most of the > >conducted > >component. > > SNIP > > Ralph: > > When you describe the success of eliminating the "conducted component", are > you talking about preventing the energy from exiting the source equipment or > preventing the energy from entering the conducted port of the victim > equipment? > > If it's the former, then you are also reducing the radiated component (which > radiates from the common powerlines). > > BTW, I have a 1 MB zip file with plots of the RF field strength that I > measured at a number of the San Francisco BART stations. I'll email the > package to anyone who would like a copy (email me directly, not through the > list). The strongest field strengths were less than 10 V/M, and all > originated from personal communication devices. > > Regards, > > Ed > > Ed Price > ed.pr...@cubic.com > Electromagnetic Compatibility Lab > Cubic Defense Systems > San Diego, CA USA > 858-505-2780 (Voice) > 858-505-1583 (Fax) > Military & Avionics EMC Services Is Our Specialty > Shake-Bake-Shock - Metrology - Reliability Analysis > > ------------------------------------------- > 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: > http://www.rcic.com/ click on "Virtual Conference Hall," > > ------------------------------------------- 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: http://www.rcic.com/ click on "Virtual Conference Hall,"
