Power consumption for controllers and drive shelves is listed in Hardware Universe.
http://hwu.netapp.com/Home/Index
On a FS8040 it sez 8.76A@100V ...
I hope this response has been helpful to you.
At your service,
Eugene E. Kashpureff, Sr.
Independent NetApp Consultant http://www.linkedin.com/in/eugenekashpureff
Senior NetApp Instructor, FastLane US http://www.fastlaneus.com/
(P.S. I appreciate 'kudos' on any helpful posts.)