>-----Original Message----- >From: Gary McInturff [mailto:[email protected]] >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:[email protected]] >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 [email protected] 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: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson: [email protected] Dave Heald [email protected] For policy questions, send mail to: Richard Nute: [email protected] Jim Bacher: [email protected] All emc-pstc postings are archived and searchable on the web at: http://www.rcic.com/ click on "Virtual Conference Hall,"
