It took a little searching, but I found a web page on UL's site that has this comparison at:
http://www.ul.com/hazloc/ref/conversion.htm which matches the NEMA250:1997, Table A-1 conversions. The web page refers to NEMA 250, "for additional details," and NEMA 250 makes the same reverse conversion statement, mentioned by Art Michael. It's not as detailed as the NFPA79:2002, Table F.5.5. There seems to be a difference of opinion as to conversion between NEMA enclosure Types and IP ratings, NFPA79 (at first blush) being the more conservative (but this may not apply across the entire chart). All only consider the first two IP characters. NEMA 250, Appendix A, paragraph 1, indicates this is doe to NEMA requirements not addressing "corrosion, rust, icing, oil, and coolants." Regards, Peter L. Tarver, PE Product Safety Manager Sanmina-SCI Homologation Services San Jose, CA [email protected] > From: Arthur Michael > Sent: Wednesday, July 02, 2003 9:05 AM > > Hi Jim, > > Where have you already found data re NEMA vs IEC ratings? > > UL offers a chart (NEMA > IP Ratings) as does > NEMA (NEMA 250, Table A-1) > for NEMA > IEC - IP Ratings); however, each > notes that the charts are to > be used only in the indicated direction (and not > the reverse). > > I expect that because the ratings are not precise > equivalents, that > discrepancies do occur and thus, the differences > in the charts you may > have found. > > Best regards, Art Michael > 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: [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] Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
