I was waiting for a reply from Ted Rook, and I don't see one, so I will take a whack at the answer.
>From what I have seen of domestic well pumps in this country, they usually use a capacitor run (split phase) motor, with extra capacitance switched in for starting. The starting capacitor causes a leading power factor, increasing power line voltage. I have seen another cause for lights getting brighter which is due to the common domestic power feed here in the US, which is 240 volts center tapped. This gives two sets of 120 volt loads in the house. If there is high resistance in the neutral (center tap) conductor, a high current load (such as a motor starting) will cause one set of lights in the house to get dimmer, while the other set gets brighter. Don Borowski Schweitzer Engineering Labs Pullman, WA John Woodgate <[email protected]>@majordomo.ieee.org on 12/05/2002 01:01:34 PM Please respond to John Woodgate <[email protected]> Sent by: [email protected] To: [email protected] cc: Subject: Re: Undervoltage/Overvoltage Effect on Household Appliances I read in !emc-pstc that Ted Rook <[email protected]> wrote (in <[email protected]>) about 'Undervoltage/Overvoltage Effect on Household Appliances' on Thu, 5 Dec 2002: >In my semi rural home 50 miles NW of NYC I have the normal 120V 60Hz domestic >supply. The well water pump starts automatically and pulls a lot of current. >Inside the house the tungsten lighting brightens about 30% for half a second >everytime the pump turns on. Why does the pump cause an *increase* in voltage? -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk 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: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: [email protected] Dave Heald: [email protected] For policy questions, send mail to: Richard Nute: [email protected] Jim Bacher: [email protected] All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list" ------------------------------------------- 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: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: [email protected] Dave Heald: [email protected] For policy questions, send mail to: Richard Nute: [email protected] Jim Bacher: [email protected] All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
