My own personal experience bears this out. on 1/10/02 3:39 PM, Patrick Lawler at [email protected] wrote:
> > I belive emissions standards were designed to allow proper operation of radios > and televisions with minimal irritation. This would include sound and video > quality. I heard this story a long time ago with respect to FCC limits. > > On the other hand, immunity standards were developed so equipment would not be > damaged, not 'lock up', and remain safe. > > While equipment might meet a 3V/m immunity standard, I'll bet if it was an > 'Intentional Receiver' like a radio (there are international radiators, why > not > intentional receivers?), it would operate poorly when separated by 1m from a > CISPR Class A noise source. Obviously, this assumes the noise was comparable > in > frequency to the victim equipment. > > On Thu, 10 Jan 2002 14:18:37 +1000, [email protected] wrote: >> At the moment I'm examining as a generic case, the potential for >> interference with Item A (tested to comply with 3V/m radiated immunity) >> caused by Item B (tested to comply with FCC or EN Class A [industrial] >> emissions). >> >> Using simple inverse distance ( E2 = E1 x d1/d2 ) extrapolation (assuming >> dominant interfering frequencies will be in the far field), I come up with >> a required separation distance of approximately 75cm to ensure the 3V/m >> immunity limit of Item A isn't exceeded by the 47dBuV/m emissions from Item >> B. >> >> Based on this, I'd expect then the risk for EMC problems should be >> relatively low provided: >> 1. A minimum separation of 1m was used between Items A & B; >> 2. No direct interconnection of A to B via cables; >> 3. Use of a mains filter and/or separate power supply sources for A & B; >> 4. The nature of Item B is such that no significant low (eg.power) >> frequency magnetic fields are emitted; >> >> Does anyone have any experience to suggest that the minimum separation of >> 1m under theses conditions would not be adequate? > > ------------------------------------------- > 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: > 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: [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: No longer online until our new server is brought online and the old messages are imported into the new server.
