Thanks for all the posts. I am on my lunch break but will be able to read all the posts again. To give a little history about this lathe, I bought it about 8 years or so ago. Right around the time hitachi seiki went bankrupt. I have not been able to acquire any manuals for it ( it is a NH-500... apparently not a Machine that was sold in the US from what I am told). It could possibly be a HT-500 but that is not confirmed. If anyone has a good resource for manuals that would be a nice help. Anyways the machine was fitted originally with a Fanuc 2000 control with an additional control used to control the drilling/headstock turret. So it has Z,X,W axes. Due to the fact I cannot get any data, parameters, and other such important data on this machine. I decided to scrap the controller and all it's components. I figured there is a lot more efficient and smaller components available now that I can use for the controls and systems. For the servos which ( I did keep the original fanuc drives) I am building the UHU servo drives for the servo control. I don't have the SCR drive for the original spindle. It has a two speed gearbox so I am not too worried about derating the spindle down a little bit. I am interested in the drives that can use the DC bus and also even one to control the existing DC motor since i am already building a massive power supply for the drives. I am sure I will have more to say tonight.
Thanks, Clint Washburn (Sent from my iPhone) On Mar 8, 2011, at 12:02 PM, Igor Chudov <ichu...@gmail.com> wrote: > On Tue, Mar 8, 2011 at 1:12 PM, Kirk Wallace > <kwall...@wallacecompany.com>wrote: > >> On Tue, 2011-03-08 at 09:16 -0800, dave wrote: >>> On Mon, 2011-03-07 at 22:03 -0800, Clint Washburn wrote: >>>> I am in the process of converting my 1978 Hitachi Seiki CNC lathe to >> EMC. >>>> It currently has a 7.5 KW dc motor that used to be powered by FUJI SCR >>>> drive. My first problem my house does not have 3 phase power. I am >> having >> ... snip >>> Just to be totally contrary if the dc motor is working fine then use a >>> rotary single phase to three phase converter. Lots of stuff on the web >>> about how to make one. It won't be perfect but probably good enough to >>> power the fuji controller. I used a 5 hp homebuilt for several years >>> before upgrading to a 30 Hp commercial job to power the Mazak. >>> The commercial one is much better balanced but the other was adequate. >>> >>> By OK I mean it balance to about 240, 240, 220 for the homebuilt. >>> The commercial is within 5 v. >> >> I use a home made rotary converter for one of my lathes. This lathe is >> not as convenient to use as the lathes with VFD's. It's kind of a pain >> to worry about turning the converter on only when I need to use the >> lathe, so I tend to not use the lathe unless I have to. Having a remote >> start might fix this. >> >> Another thing is that for all static and rotary converters I have seen, >> the single phase is passed right through and the converter creates a 90 >> (or 270) degree phase, so you get 0, 90 and 180 degrees instead of 0, >> 120 and 240 degrees. A three phase motor should run more smoothly with >> evenly spaced phases, but on the other hand, I haven't noticed any >> problem with my lathe that uses the converter. >> >> > This is not true, phases are evenly spaced on mine. I use run capacitors. My > voltages are very close to each other L1-L2, L1-L3, L2-L3. > > i > > >> Before I had any VFD's, I was thinking about making a three phase >> generator. I only have 50Amps feeding the shop, so I have to be very >> careful how I use power. My 300Amp welder needs 150Amps of 240VAC >> (36kW). Having a 30 or 40kW generator might fix the problem. For those >> with plenty of single phase amperage, the generator could be run with a >> single phase motor. >> >> Power factor may play a roll with these issues. I don't know much about >> the subject, but the Pro's seem to worry about it. >> >> For the Hitachi lathe, I would tend to figure out what the SCR drive >> needs and leave it in place. SCR's need zero Volt crossing to trigger, >> so some sort of AC seems to be needed, unless the drive converts the >> input to DC and then creates its own AC from that. >> -- >> Kirk Wallace >> http://www.wallacecompany.com/machine_shop/ >> http://www.wallacecompany.com/E45/index.html >> California, USA >> >> >> >> ------------------------------------------------------------------------------ >> What You Don't Know About Data Connectivity CAN Hurt You >> This paper provides an overview of data connectivity, details >> its effect on application quality, and explores various alternative >> solutions. http://p.sf.net/sfu/progress-d2d >> _______________________________________________ >> Emc-users mailing list >> Emc-users@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/emc-users >> > ------------------------------------------------------------------------------ > What You Don't Know About Data Connectivity CAN Hurt You > This paper provides an overview of data connectivity, details > its effect on application quality, and explores various alternative > solutions. http://p.sf.net/sfu/progress-d2d > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------------ What You Don't Know About Data Connectivity CAN Hurt You This paper provides an overview of data connectivity, details its effect on application quality, and explores various alternative solutions. http://p.sf.net/sfu/progress-d2d _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
