Duncan, Here is the definition of "Direct Plug-in Equipment" from the EN60950 standard-"Equipment that is intended to be used without a power supply cord; the mains plug forms an integral part of the equipment enclosure so that the weight of the equipment is taken by the socket-outlet"
These are what I refer to as wall transformers. They are small (at most about 3 x 4 x 2") units that plug in the wall and typically have a low voltage DC output for things like printers, portable radios, etc. Even if your unit was considered "Direct Plug-in Equipment" that part of the test would not be applicable since your equipment is Class I and therefore by definition has an equipment grounding conductor. I do not know the rationale behind the S1 requirement. I hope this answers at least some of your questions. Kurt Andrews Compliance Engineer Tracewell Systems, Inc. 567 Enterprise Drive Westerville, Ohio 43081 voice: 614.846.6175 toll free: 800.848.4525 fax: 614.846.7791 http://www.tracewellsystems.com/ <http://www.tracewellsystems.com/> -----Original Message----- From: duncan.ho...@snellwilcox.com [SMTP:duncan.ho...@snellwilcox.com] Sent: Friday, May 04, 2001 12:18 PM To: emc-p...@majordomo.ieee.org Subject: UL 1419 Earth Leakage Group, Are there any group members who are familiar with the earth leakage requirements of UL1419 (Standard for Safety - Professional Audio and Visual equipment) in section 41.1 Our equipment is a detachable power cord connected, class 1 appliance rated at 100 -250 V. Section 41.1.9 of the standard clearly states that 'Switch S1 as shown in figure 41.1 is used only for direct plug in power supply products that do not employ an equipment grounding conductor...' (S1 acually open circuits the neutral conductor) My three questions are: - Would they use S1 when leakage testing our type of equipment? - What is the definition of 'direct plug in' (it is not mentioned in the definitions section) - For 'direct plug in' equipment what is the reason for operating this switch i.e what is the rationale behind the provision of S1. Any help or comments would be greatly recieved. Many thanks in advance, Duncan Hobbs, Product Safety Engineer Snell and Wilcox Ltd. ------------------------------------------- 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: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson: pstc_ad...@garretson.org Dave Heald davehe...@mediaone.net 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.rcic.com/ click on "Virtual Conference Hall," ------------------------------------------- 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: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson: pstc_ad...@garretson.org Dave Heald davehe...@mediaone.net 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.rcic.com/ click on "Virtual Conference Hall,"
