I read in !emc-pstc that Rich Nute <ri...@sdd.hp.com> wrote (in <200201232308.paa21...@epgc264.sdd.hp.com>) about 'Harmonic current emissions', on Wed, 23 Jan 2002:
>The additional cost for a PF-corrected SMPS is >not a constant adder; it is proportional to >power output. One must use higher power PF >components for higher power output. But the whole cost is roughly proportional to power. The figures I quoted refer to 'a normal PC power supply', which I suppose is a 200 or 250 W unit. > >Having actually purchased production quantities >(1995) of the same SMPS in both non-PF-corrected >and PF- corrected schemes, the additional cost >for PF-corrected ranged from 50% to 75% higher >than the non-PF-corrected supply. In 1995, corrected supplies were relatively new and quantities were low. When the CDV for the Millennium Amendment was circulated, we in UK had protests from power supply manufacturers, saying that it undermined their market for corrected supplies, **which they were almost entirely concentrating on**. In fact, of course, the majority of their sales still go into Class D products. > > >More recently (2001), the cost difference was >indeed lower -- only about 25-30% premium. That still seems high. How does it compare with my USD figures, though? (;-) > >I suspect your sources wanted to sell PF-corrected >SMPS's and exaggerated on the low side. The figures I quoted did not come from a sales situation but information supplied to the IEC WG. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk After swimming across the Hellespont, I felt like a Hero. PLEASE do NOT copy news posts to me by E-MAIL! ------------------------------------------- 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: No longer online until our new server is brought online and the old messages are imported into the new server.
