John, I think it is finally done... sorry for the delay.
http://gnipsel.com/shop/rpc/rpc.xhtml John John Crane wrote: > John, > > Thanks for the update. > > JRC > > On Sun, Mar 27, 2011 at 6:02 AM, John Thornton<bjt...@gmail.com> wrote: > > >> I can't find my drawings atm, so I'm recreating them from scratch and >> will post them as soon as done. Just wanted to let you know I did not >> forget although sometimes I do. >> >> John >> >> John Crane wrote: >> >>> Thanks, >>> >>> John R. Crane >>> >>> On Mon, Mar 21, 2011 at 7:27 AM, John Thornton<bjt...@gmail.com> wrote: >>> >>> >>> >>>> John, >>>> >>>> I'll dig out my schematic and make sure it is up to date and figure a >>>> way to post it to the list. >>>> >>>> John >>>> >>>> John Crane wrote: >>>> >>>> >>>>> John, >>>>> >>>>> I would like to know more about the way you have engineered your phase >>>>> converters. I am in the process of adding this capability in my shop. >>>>> >>>>> Thanks, >>>>> >>>>> John R. Crane >>>>> >>>>> On Thu, Mar 17, 2011 at 5:53 AM, John Thornton<bjt...@gmail.com> >>>>> >> wrote: >> >>>>> >>>>> >>>>> >>>>>> I have three rotary phase converters. The are all using a potential >>>>>> relay for the start caps and a relay that pulls in the mains. So I >>>>>> >> don't >> >>>>>> have to hold the push button and if the power drops out for a few >>>>>> seconds the phase converter does not try and restart without the start >>>>>> caps. I've not had the fun of blowing anything up when building them. >>>>>> They are all balanced phase to phase within a couple of volts. However >>>>>> phase to phase the run caps are very different in order to get the >>>>>> voltage phase to phase to balance. I can post some details if anyone >>>>>> >> is >> >>>>>> interested... >>>>>> >>>>>> John >>>>>> >>>>>> Dave wrote: >>>>>> >>>>>> >>>>>> >>>>>>> Back when I put my 10 hp phase converter together, I found some >>>>>>> >> charts >> >>>>>>> on the web someplace about suggested capacitor sizing. I found a >>>>>>> >>>>>>> >>>> cheap >>>> >>>> >>>>>>> supply of capacitors at Mendelson's in Dayton, Ohio >>>>>>> and bought a small box of them. I ended up using I believe, 4 - 330 >>>>>>> >>>>>>> >>>> uf >>>> >>>> >>>>>>> 330 volt units as starting caps and 4- 135 uf run caps. I use a >>>>>>> >> push >> >>>>>>> button to start the motor and as long as I hold the button >>>>>>> down the starting caps are wired into the circuit. When the motor >>>>>>> >>>>>>> >>>> spins >>>> >>>> >>>>>>> up I release the button. I tried to use a voltage sensitive relay, >>>>>>> like the ones used on refrigeration systems and AC systems, but >>>>>>> it was not reliable probably due to the high current from the large >>>>>>> number of caps. There is also a motor contactor that seals itself in >>>>>>> via the button push. That way if the line power drops, the >>>>>>> >> contactor >> >>>>>>> drops out and the converter idler motor and he >>>>>>> attached slave motors are powered down. >>>>>>> >>>>>>> The math relating to how this works gets even more complicated when >>>>>>> >> you >> >>>>>>> consider the effects of hooking a 3 phase motor that you are going to >>>>>>> start (a slave motor) across the the idling phase converter motor. >>>>>>> For a brief period of time, the idler motor becomes a generator. >>>>>>> >> The >> >>>>>>> rotor slows slightly and the energy in the rotor pumps power into the >>>>>>> three phases and spins up >>>>>>> the slaved motor. It works very well. >>>>>>> >>>>>>> During experimentation, it is very obvious when more starting >>>>>>> >>>>>>> >>>> capacitors >>>> >>>> >>>>>>> are required as the motor will simply not spin up. >>>>>>> Adding more run caps helps balance the phases but they never really >>>>>>> fully balance. >>>>>>> >>>>>>> Safety glasses are very good idea when experimenting. Starting >>>>>>> >> caps >> >>>>>>> go off like firecrackers if you overstress them. They are only >>>>>>> designed to be switched in for a few seconds. >>>>>>> >>>>>>> A source of cheap starting caps is a really good idea if you want to >>>>>>> >> do >> >>>>>>> some phase converter experimentation. I blew up several of them. >>>>>>> >>>>>>> Dave >>>>>>> >>>>>>> On 3/14/2011 9:01 PM, Jon Elson wrote: >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>>> >>>>>>>> >>>>>>>>> On 14 March 2011 10:50, John Thornton<bjt...@gmail.com> >>>>>>>>> >> wrote: >> >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>>> Is it not amazing that the hillbillies from backwoods Missouri >>>>>>>>>> >> with >> >>>>>>>>>> >>>> a >>>> >>>> >>>>>>>>>> 3rd grade education can make a rotary phase converter without all >>>>>>>>>> >>>>>>>>>> >>>> the >>>> >>>> >>>>>>>>>> math... >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>> Of course! The trick is the windings in the motor do all the math >>>>>>>> >> for >> >>>>>>>> you, all you need to do is hook up the wires. >>>>>>>> >>>>>>>> Jon >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>> >>>> >> ------------------------------------------------------------------------------ >> >>>> >>>>>> >>>>>>>> Colocation vs. Managed Hosting >>>>>>>> A question and answer guide to determining the best fit >>>>>>>> for your organization - today and in the future. >>>>>>>> http://p.sf.net/sfu/internap-sfd2d >>>>>>>> _______________________________________________ >>>>>>>> Emc-users mailing list >>>>>>>> Emc-users@lists.sourceforge.net >>>>>>>> https://lists.sourceforge.net/lists/listinfo/emc-users >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>> >>>>>>> >>>>>> >>>> >> ------------------------------------------------------------------------------ >> >>>> >>>>>> >>>>>>> Colocation vs. Managed Hosting >>>>>>> A question and answer guide to determining the best fit >>>>>>> for your organization - today and in the future. >>>>>>> http://p.sf.net/sfu/internap-sfd2d >>>>>>> _______________________________________________ >>>>>>> Emc-users mailing list >>>>>>> Emc-users@lists.sourceforge.net >>>>>>> https://lists.sourceforge.net/lists/listinfo/emc-users >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>> >>>>>> >>>> >> ------------------------------------------------------------------------------ >> >>>> >>>>>> Colocation vs. Managed Hosting >>>>>> A question and answer guide to determining the best fit >>>>>> for your organization - today and in the future. >>>>>> http://p.sf.net/sfu/internap-sfd2d >>>>>> _______________________________________________ >>>>>> Emc-users mailing list >>>>>> Emc-users@lists.sourceforge.net >>>>>> https://lists.sourceforge.net/lists/listinfo/emc-users >>>>>> >>>>>> >>>>>> >>>>>> >>>>> >>>> >> ------------------------------------------------------------------------------ >> >>>> >>>>> Colocation vs. Managed Hosting >>>>> A question and answer guide to determining the best fit >>>>> for your organization - today and in the future. >>>>> http://p.sf.net/sfu/internap-sfd2d >>>>> _______________________________________________ >>>>> Emc-users mailing list >>>>> Emc-users@lists.sourceforge.net >>>>> https://lists.sourceforge.net/lists/listinfo/emc-users >>>>> >>>>> >>>>> >>>> >>>> >> ------------------------------------------------------------------------------ >> >>>> Colocation vs. Managed Hosting >>>> A question and answer guide to determining the best fit >>>> for your organization - today and in the future. >>>> http://p.sf.net/sfu/internap-sfd2d >>>> _______________________________________________ >>>> Emc-users mailing list >>>> Emc-users@lists.sourceforge.net >>>> https://lists.sourceforge.net/lists/listinfo/emc-users >>>> >>>> >>>> >>> >> ------------------------------------------------------------------------------ >> >>> Enable your software for Intel(R) Active Management Technology to meet >>> >> the >> >>> growing manageability and security demands of your customers. 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