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 (talkcontribs) 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)