Dave - Removing the load removes flux from the core. My experience has shown that some transformers vibrate only for higher current load conditions (not necessarily at saturation) and there's negligible or no vibration with only magnetization current supporting flux in the core. Replacing the in situ load with a resistive load would demonstrate if the phenomenon John is describing is the root cause. This is more seat-of-the pants than your method but could be more direct with regard to effects load type.
Regards, Peter L. Tarver, PE [email protected] > From: [email protected] > Sent: Tuesday, December 20, 2005 9:01 AM > > John, > > You have helped me to think about this differently. To tell > if it is the > transformer secondary load that is the culprit one can disconnect the > load. If it still hums then the load is not the problem. > _____________________________________________________________________________ Scanned by Sanmina-SCI eShield _______ _____________________________________________________________________ - 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
