Path: utzoo!mnetor!uunet!husc6!uwvax!oddjob!ncar!ames!ucsd!sdcsvax!ucsdhub!hp-sdd!hplabs!hpda!hpcupt1!hpcuhb!hpscdc!rkarlqu From: rkarlqu@hpscdc.HP.COM (Rick Karlquist) Newsgroups: sci.electronics Subject: How are power line voltages determined? Message-ID: <5770004@hpscdc.HP.COM> Date: 10 May 88 01:07:40 GMT Organization: HP, Santa Clara, CA Lines: 13 Does anyone out there know how the "official" power line voltages are arrived at. It seems that in the beginning, there was 110 volts (at least all the old timers talk about 110) and now you often see 115 volts listed as nominal. However, you often see equipment marked as 120 volts or surprisingly 117 volts. Where do they come up with an odd ball number like 117 anyway. My guess is its 115 + 2%, but that's not based on anything. Will the real power line voltage please stand up! Rick Karlquist Hewlett-Packard rkarlqu%hpscdc@hplabs.hp.com