A failure in PFC section most onerous when a surge finds its way to the choke/diode/switch node. Any significant voltage 'reflected' into the gate of the PFC transistor will typically cause power supply to puke it guts.
Looks like data that would indicate a root-cause failure remains elusive - seems to be a need something non-intrusive that is self-powered and can get kicked yet stand back up for more abuse (please sir, may I have another...). During 2013, tried several commercial loggers over a six-month period and most did not survive the end-use environment . The two that lived through their ordeals had insufficient bandwidth, or had insufficient dynamic range, or had immunity problems, or used too much power, etc. So ignored the 'Not Invented Here' accusations and rolled own design. Second fielded version worked ok and management wanted to turn it into a standard product - but were able to convince otherwise by explaining the level of customer support required for various windoze computers that would be used to suck in the log files; and that marketing said could sell no more than 3 units per month of a specialty product (mostly used to monitor power converters, transformers, and reactors used on PV arrays). My latest incarnation of The One True Monitor Box looks at seven thermocouple channels, four Vdc (200-1500V) channels, three RMS (230-480V), two light sensor channels, and seven current channels; an array of four peak V (envelope detector) channels that can be paralleled with the voltage channels(mostly to detect when to go to hi-speed sample rate and use different data structure); and four comparator channels (hi-rate event triggers). The support from the good engineers at LT, ADI, Micrel, and TI was instrumental (pun intended) in this design. Have recently started using these loggers to monitor long-term Type Tests where there is a risk that the test conditions might kill my standard lab setup (Agilent34970/computer combo - $100 vs $3000 USD of equipment). The (im)moral of the story is that compliance engineering thrives where reliable *end-use* empirical product data is available. 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]>
