On Thu, 2012-03-08 at 03:19 -0800, charles green wrote: > it is a cost sensitive application, as always, and limited to single > 115v phase mains supply. there are the sherline spindles/motors with > decent speed controls, but sherline stuff is kinda spendy. i dont > recall seeing any retail vfd pages, but i'm thinking in the many H$ to > a K$ or so for a drive, and the smaller power motors i've come across > replacing are a few hundred on their own. in contrast, a bench > grinder from a home store or walmart can go as low as $40. ..hmm. i > wonder how hard it would be to rewind one?
In the US, 240 Volts AC is available from a dryer outlet and 240 VAC usually runs to the kitchen for an electric oven, so there may be a way to get 240 to where you need it that isn't too hard to rig up. I have a 40 Amp dryer type extension cord that I plug my machines into. It's not very convenient because I can only run one machine at a time, but it works for now. I also have a large transformer that can boost 120 VAC to 240 VAC. With 120 VAC outlets rated for 15 Amps max., I can only get 7 Amps of 240 VAC from the transformer, but this is enough for testing most of my VFD's. This one is similar: http://www.ebay.com/itm/290647166101 eBay has some cheap VFD's: http://www.ebay.com/itm/290580719222 Motors are a problem, but this might work: http://www.ebay.com/itm/170795747608 it runs on 120 VAC three phase, so a VFD would need to be set up to limit the output voltage, but that's easy to do. DC treadmill motors work well with KBIC type speed controllers but these can be harder to find and can be more expensive. I tend to look at what I have on hand or what I can find on trash day or in dumpsters before I start looking at new stuff. -- Kirk Wallace http://www.wallacecompany.com/machine_shop/ http://www.wallacecompany.com/E45/index.html California, USA ------------------------------------------------------------------------------ Virtualization & Cloud Management Using Capacity Planning Cloud computing makes use of virtualization - but cloud computing also focuses on allowing computing to be delivered as a service. http://www.accelacomm.com/jaw/sfnl/114/51521223/ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
