On Mon, 2012-05-28 at 08:43 +0100, Dave Caroline wrote: > I think most people looking at idler rotary converters dont actually > scope the phases > I only came across one site stating the obvious > > given the basic diagram of > > 120 ac to motor P1 and output phase L1 > neutral--nc > 120 ac to motor P3 and output phase L3 > Capacitor P1 to P2 and to output phase L2 > > will notice the 180 deg phase of the two 120 lines are connected directly > to L1 and L3 so that is at 180 degrees not the 120 it should be. > So L2 is some where in between L1,L3 but if it was 120 degrees from L1 > then it would be 60 from L3 > the voltage imbalance would be silly so it is adjusted to be 90 form > L1 and it just about works ... snip
I made this argument a couple of years ago and I was eventually persuaded that I was mistaken. In trying to understand why, I made this diagram. http://wallacecompany.com/machine_shop/EMC2/three_phase_converter-1b.png This may change if the Neutral is used and taken into account, but this is my current understanding of how the most popular rotary converters work. I think a key point is that a Phase is not just one wire, it is the signal created by two wires. That is why two 120 VAC sources, say L1 and L2, no matter what their relation to Neutral is, produces a single phase. For a converter, the other two phases are not L2 and L3, but L1-L3 and L2-L3. -- Kirk Wallace http://www.wallacecompany.com/machine_shop/ http://www.wallacecompany.com/E45/index.html California, USA ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
