Check this site http://www.lmphotonics.com/. You may have been here before. It has a lot of engineering information. The great thing is that it has information on bus bars so that we won't ever have to answer questions on this subject again.
MarkE, the site owner and occasional poster in here, is a friend of mine and a wealth of practical knowledge. He aslo runs another forum called LMP Forums that you can link to from that main website. Great info in there as well, lots of good discussions on VFDs, Soft Starters and so-called "Energy Savers".
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** All I every really wanted to be, was... A LUMBERJACK!.**