2012/11/20 andy pugh <bodge...@gmail.com>: > On 20 November 2012 11:23, <kqt4a...@gmail.com> wrote: > >> I see a great many lower priced switching supplies > > Possibly because a motor power supply contains too few components to > bother selling as a unit. > A transformer, rectifier and capacitor is all that is needed. And the > transformer may be optional.
For my last 3 machines I used ~1kW transformer with 220VAC input and 20VAC output, which gives ~28 VDC after rectification. My current build has 800W transformer with 20VAC output, that machine has 2 7i39 drives, 10A for each motor is 40A total. That is what transformer rated for, but I am now curious to find out, if capacitors, when they will be charged, will not actually draw a lot more current. What do others think about it? How can I calculate that? BTW those are custom-made for me torroidal transformers by a company in Poland. The 1kW transformer cost me 200EUR, including shipping, the 800W was 150EUR. I managed to burn down 50A rectifier bridge (despite the heatsink), but I was not able to feel by hand that transformer had warmed even a little. They work really great. If anyone ever needs, let me know, I can pass their contacts. -- Viesturs If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto ------------------------------------------------------------------------------ Monitor your physical, virtual and cloud infrastructure from a single web console. Get in-depth insight into apps, servers, databases, vmware, SAP, cloud infrastructure, etc. Download 30-day Free Trial. Pricing starts from $795 for 25 servers or applications! http://p.sf.net/sfu/zoho_dev2dev_nov _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
