Hi, Ned
What you've stated below is a misapplication of the standard. §4.5.1 (you quote from 60950/60950-1) is related to normal operating condition testing, rather than the abnormal operating condition of ventilation opening blockage. I also doubt that instructions will include starving of necessary ventilation under normal operating conditions, unless the technical writer and the engineers weren't on speaking terms. ;> Blocked ventilation testing would be addressed by one of the §s under §5.3. Even under abnormal operating conditions in a rack, the standard does not anticipate all ventilation openings are blocked. Whether or not the equipment is rack mounted, they're over testing. Regards, Peter L. Tarver, PE [email protected] > -----Original Message----- > From: Ned Devine > Sent: Tuesday, November 25, 2003 12:19 PM > > Hi, > > For rack mounted equipment, UL requires all vent > openings be blocked. > See 4.5.1 "...Equipment intended for building-in > or rack-mounting, or > for incorporation in larger equipment, is tested > under the most adverse > actual or simulated conditions permitted in the > installation > instructions." > > If it is not rack mounted, then they are over testing. > > Ned Devine > Entela Inc > This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ieee-pses.org/ To cancel your subscription, send mail to: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: [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.ieeecommunities.org/emc-pstc
