In message <[email protected]>, dated Mon, 23 Apr 2007, Brian O'Connell <[email protected]> writes:
>An attempting to discern test conditions with conducted emissions >(EN61000-3-2) requirement. > >The customer's end item is a printer that will be rated to consume an >average of 60W, but will have a peak input power of approx 200W for >'several' seconds. I am not yet certain what the duty cycle will be, >but the design engineer assures me that the 'average' input power will >be 60W. For 6.2.2 of the standard, the average input power is irrelevant. > >Because the peak input power will occur at other than start or stop, >clause 6.2.3.2 does not apply, so the measurement time constant would >seem to be the 1.5 sec that would be centered during a peak power >'surge' period. Yes; this 'surge' is presumably due to a heater, a linear load, and that means that the product is most unlikely not to comply. >Also table Z1 You are using the 2000 edition, which is OK, but there is a 2006 edition now. >indicates an observation period of 10 cycles, because Tcycle is less >that 2.5 sec. > >1. Definition of "equipment cycle" ? It's easier to define 'equipment cycle time', and deduce the meaning of 'equipment cycle'. 'Equipment cycle time' is the time from the equipment being at an initial, stable state until it returns to that state. In case of doubt, you apply 6.2.3.1; if the results of repeated tests with a duration T are within +/-5%, T is long enough, in the sense of Table Z1 (Table 4 now). >2. Are the above test conditions and assumptions correct ? With my additional explanations, I hope so! >3. What important questions have I failed to ask ? Nothing springs to mind at present. -- OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk There are benefits from being irrational - just ask the square root of 2. John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to [email protected] Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas [email protected] Mike Cantwell [email protected] For policy questions, send mail to: Jim Bacher: [email protected] David Heald: [email protected] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc ______________________________________________________________________ This email has been scanned by the MessageLabs Email Security System. For more information please visit http://www.messagelabs.com/email ______________________________________________________________________
