I think you are not correctly interpreting you power requirements.  You have 3 chassis w/ 4 PS each and are looking to supply twelve 16A circuits.  I put in 2 chassis w/ 4 PS each and it's working fine using 2 x 30A circuits into a Server Technology ...

Just a follow up to say that everything is working fine with our Server Technology Smart CDU.

Check out Server Technology and their Smart CDU line of products:  http://www.servertech.com/products/smart-pdus/smart-pdu-cs-12hdHere is a document covering use with UCS servers:  http://www.servertech.com/uploads/documents/0000/0611/Cisco-Server-Te...