Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!uwm.edu!rpi!sci.ccny.cuny.edu!phri!roy From: roy@phri.nyu.edu (Roy Smith) Newsgroups: sci.electronics Subject: Re: Watt Hour Meters Message-ID: <1990Jan11.015852.7031@phri.nyu.edu> Date: 11 Jan 90 01:58:52 GMT References: <25675@cup.portal.com> <1262@island.uu.net> Sender: news@phri.nyu.edu (News System) Distribution: usa Organization: Public Health Research Institute, New York City Lines: 38 In article <1262@island.uu.net> rich@island.uu.net (Rich Fanning) writes: > Do the utility meters on the average house measure true watts Actually, they measure watt-hours, but you knew that; I'm just being pedantic. Large industrial users are not only "encouraged" to keep a reasonable power factor, but they also get zapped with a hefty penalty if their peak load (I'm not sure if kVA or kW) ever goes past some preset limit. Anybody know what the total average power factor on the power grid is? I would imagine it must be massively lagging, what with motors and transformers being most of the load. I can't think of any typical capacitive loads on the power grid. I know it is possible to make a synchronous motor have a leading power factor with proper external excitation, but have no idea how often that is done. If the above doesn't make sense, try interchanging all instances of leading and lagging; I never could keep them straight. Does current lag voltage or does voltage lead current? Pretty arbitrary, isn't it? I think of capacitive as leading and inductive as lagging. Did I get that right? I know about ELI the ICE man, but that's a pretty bad mnemonic because you can interpret either way! Now, for another question. A while ago, I was wandering around in the basement, looking at the power connections. No, not my basement, where I work basement. The building engineers are wonderfully lax about not locking doors. Anyway, behind the panels with the 5000 amp breakers were a couple of rather ordinary-looking electric meters and boxes with wire seals on them. Some of the boxes said "Con Edison" on them, which seems normal, but some of them said "New York Power Authority" which got me curious. Why would the NYPA have a sealed box in a not-particularly-special building in Manhattan? What's in that box? Could the NYPA actually be interested in the few measly MW our building must draw? Isn't that sort of like the Federal Reserve worrying about whether my personal checkbook gets balanced? -- Roy Smith, Public Health Research Institute 455 First Avenue, New York, NY 10016 roy@alanine.phri.nyu.edu -OR- {att,philabs,cmcl2,rutgers,hombre}!phri!roy "My karma ran over my dogma"