I apologize if this has been answered already, but I could not find it.  I am playing as the Vasari and have the Vorastra Titan upgraded with the Phase Cannon.  I actually have all research done as well.  However, I have yet to see the darned thing fire on ANYTHING.  It has not shown any indication of a cooldown, and I have engaged Starbase's, cap ships and other Titans.  Can anyone help me out with how to make sure I have it correct and how I can use the Phase Cannon other than having a nice icon?  Thanks in advance.