User talk:Jeh/Archives/2015/03
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Power Factor
Re: your comment "I never could understand how the power factor formula could result in a negative number. If you're "returning power to the source" then your putative load is not a load at that time, it's the source, and vice versa. So your power factor is still a positive number. Granted that meters will show negative numbers, that makes complete sense in this context, but it is merely an indication that the source and sink have swapped roles."[1]
What we call things is often a matter of convention. A classic example is calling a terminal on an AA battery "-" when it is a source of electrons.
In the case of power factor, there is a current, standards-based definition and an obsolete definition used on some very old test equipment.
Current, standards-based definition: Phase angles (leading and lagging) in the range of -90° to -0° and +0° to +90° have a positive power factor. Phase angles in the range of -90° to -180° and +180° to +90° have a negative power factor. Power factor readings do not indicate leading or lagging. Modern meters often have a separate display giving the phase angle.
Obsolete convention: Phase angles (lagging) in the range of -90° to -0° have a negative power factor. Phase angles (leading) in the range of +0° to +90° to have a positive power factor. Phase angles in the range of -90° to -180° and +90° to +180° are undefined. Some meters using the obsolete convention incorrectly show -90° to -180° as having a power factor in the range of -1.0 to -2.0. Some incorrectly "peg the needle" at -1.0. Some display "error". Some incorrectly give the same reading for -45° and -135° (this appears to be the source of the fringe theory). Also, some meters using the obsolete convention display "-" for leading and "+" for lagging while others display "+" for leading and "-" for lagging.
There is more on this at http://powerstandards.com/Shymanski/draft.pdf -- a paper written by by Alex McEachern, (Author of Electric Power Measurements and Handbook of Power Signatures, Chair of IEEE 1159.1 (Power Quality Measurements)]) specifically to correct Wtshymanski's WP:FRINGE claim that "power factor can only be positive", a claim that has only been published in one place (that we've found so far), in the form of an error in a single IEEE standards document -- and Alex McEachern is the chair of the IEEE committee that made the error. --Guy Macon (talk) 06:09, 7 March 2015 (UTC)
- ok, thanks for replying. Jeh (talk) 06:48, 7 March 2015 (UTC)
Word marks and Danny Cohen
Dear Jeh, I would highly appreciate if you comment on my latest edits in Talk:Endianness/Archives/2015/April#Wordmarks and Talk:Endianness/Archives/2015/March#Danny Cohen. Thanks a lot. --Nomen4Omen (talk) 10:52, 27 March 2015 (UTC)
"Development of Windows (version)" pages
I wanted to bring back the Development of Windows (Version) pages! — Preceding unsigned comment added by WikiParc (talk • contribs) 12:29, 29 March 2015 (UTC)
- Yes. You're trying to revert changes that were done almost a year ago. If you want to do that, please open discussions at the respective articles' talk pages. I doubt you'll get consensus, but you can try it. You certainly do not have consensus for such a change now.
- Note that the "Development of..." pages that were deleted were largely unsourced, non-encyclopedic content. After that was deleted, the remainder was easily small enough to fit in the parent article. That situation has not changed.
- Please do not discuss this question further here; discussions of article content belong on that article's talk page, not on any user's talk page where no one else is likely to see it. Jeh (talk) 15:37, 29 March 2015 (UTC)