Bob, UL 60950 1.4.14 states that faults shall be applied in turn, and one at a time. On the other hand I take a look at the practical operation of the unit being tested. For example one of our units is a floor standing unit that sits off the ground by about 2 inches. Since there will always be paper around my unit it would be safe to assume that some one may stick a small stack of paper under the unit (I have done it) and therefore block my intake vents. If the paper is big enough in size they could also inadvertently block the exhaust vents as well by doing the same thing.
So I typically block all the vents of my printers when I do testing. This will assure that the printer will operate and fail safely in the event that the operator wants to store important documents under our printers. Regards, Josh From: Robert Johnson [mailto:robe...@rcn.com] Sent: Tuesday, November 25, 2003 7:56 AM To: emc-p...@majordomo.ieee.org Subject: Blocked ventillation testing I have been requested by UL-HongKong to the blocked ventillation abnormal testing with all vents on all side blocked simultaneously. My previous experience has been that one side is blocked at a time. Blocking more than one side at a time was considered multiple faults. If it passes blocking all vents at once shortens test time, but is this method necessary? What is the experience of others? Bob Johnson ITE Safety 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: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: emc_p...@symbol.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc 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: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: emc_p...@symbol.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
