Voltage varies like water pressure and essentially for the same reasons but electrically. Amperage is directly related to voltage as in the formula A=W/V where A=Amps, W=Watts (a unit of work like HP) and V=Voltage. As our friend from Belgium pointed out single phase is not the best way to transfer high power needs but 30-40 amps is in the realm of household gear like water heaters, dryers, stoves, well pumps, etc. I don't think there's any effect on soft start since that's a function of the starter relay and not the incoming raw power. You could compensate for the voltage loss with a giant Variac but I don't know if such an animal is available. When I was young a friend and I got a great deal on some 3 phase woodworking tools and used a big single phase motor to run a small three phase motor as a generator but that was a doctor science experiment by kids with too much creativity and too little sense.
On Wed, Aug 26, 2009 at 9:39 AM, Matthew J. Willis<[email protected]> wrote: > I think you are going to be proven correct... > > > Why the drop to 106, 108, 112? Amps were fine 33-38 > > > > > Matthew J. Willis, CET > Automatic Fire Sprinklers > Norred Fire Systems L.L.C. > 318-387-1134 Voice > 318-387-1163 Facsimile > [email protected] > -----Original Message----- > From: [email protected] > [mailto:[email protected]] On Behalf Of Todd Williams > Sent: Wednesday, August 26, 2009 11:35 AM > To: [email protected] > Subject: Re: 3 from 1 > > Thanks guys. I didn't look in the commentary. I rejected the idea > because it seemed like it could be more trouble than it is worth. > > > > At 12:26 PM 8/26/2009, you wrote: >>Todd, >> >>20-A.9.2.2 in the 2007 edition. Not prohibited but not recommended. >> >>On Wed, Aug 26, 2009 at 9:12 AM, Todd Williams<[email protected]> wrote: >> > You may need to have an electrical engineer review the installation. >> > I did a single phase pump a few years ago and ran into electrical >> > problems (for which I was blamed). Hired an EE and he went through >> > and found the electrician messed up the installation from the service >> > right through to the pump as well as the generator feed and >> > connection. Didn't have a converter, but did have two transformers >> > because the electrician told us the wrong voltage (208 v. 240 - for >> > which I was also blamed). >> > >> > BTW, what section of the Code says Phase Converters are not allowed? >> > I couldn't find that at the time, but had rejected the idea anyway. >> > >> > >> > >> > >> > At 11:58 AM 8/26/2009, you wrote: >> >>I need some education of Phase Converters. >> >> >> >> >> >> >> >>A 300 gpm Fire Pump (Tank fed), is supplied by one of these things. > Single >> >>phase only is available, so one of these has been installed to >> make it work. >> >>Installed in '06-07ish, just replaced main board in controller. I was > there >> >>to do test following part replace. 240vac, dropped to 106-108 across the > 3 >> >>as indicated on panel. Middle leg showed 422vac in event log, as high > peak. >> >>When started, pump shaft (vertical) jumped up and down repeatedly. We > red >> >>tagged it and are waiting on word from electricians. Pump Motor checked > out >> >>fine. I know they are not allowed, but it was approved, so., I >> just test it. >> >> >> >> >> >> >> >>R/ >> >> >> >>Matt >> >> >> >> >> >> >> >>Matthew J. Willis, CET >> >> >> >>Automatic Fire Sprinklers >> >> >> >>Norred Fire Systems L.L.C. >> >> >> >>318-387-1134 Voice >> >> >> >>318-387-1163 Facsimile >> >> >> >>[email protected] >> >> >> >> >> >> >> >>_______________________________________________ >> >>Sprinklerforum mailing list >> >>[email protected] >> >>http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum >> > >> > Todd G. Williams, PE >> > Fire Protection Design/Consulting >> > Stonington, Connecticut >> > www.fpdc.com >> > 860.535.2080 >> > _______________________________________________ >> > Sprinklerforum mailing list >> > [email protected] >> > http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum >> > >> >> >> >>-- >>Ron Greenman >>Instructor >>Fire Protection Engineering >>Bates Technical College >>Tacoma, WA >> >>Member: >>SFPE, ASCET, NFPA, AFSA, NFSA AFAA >>_______________________________________________ >>Sprinklerforum mailing list >>[email protected] >>http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum > > Todd G. Williams, PE > Fire Protection Design/Consulting > Stonington, Connecticut > www.fpdc.com > 860.535.2080 > _______________________________________________ > Sprinklerforum mailing list > [email protected] > http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum > > _______________________________________________ > Sprinklerforum mailing list > [email protected] > http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum > -- Ron Greenman Instructor Fire Protection Engineering Bates Technical College Tacoma, WA Member: SFPE, ASCET, NFPA, AFSA, NFSA AFAA _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum
