What is the purpose of the MOV in this situation?
What is the MOV Joule dissipation rating (can it dissipate the expected overvoltage)? Is the MOV protected by a fuse? (An equipment d.c. bus is not likely to have high-voltage transients.) -----Original Message----- From: Brian Oconnell [mailto:[email protected]] Sent: Monday, January 26, 2015 11:56 AM To: [email protected] Subject: [PSES] OSM decision Was reviewing customer's construction where a 475V MOV was across the (floated) 420Vdc bus. Said this was bad idea, and they referred me to OSM/EE decision sheet 09/01 for EN60950-1:2006; which says ok to do whatever you want with a VDR on primary side that is not connected to mains. Can think of more than one SFC that would result in this combination of circuit configuration and component ratings making a mess. Any record of TC108 having affirmed this? Thanks, Brian - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <[email protected]> All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe) 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]>
