First of all
Shield battery it's a protoss building, protoss buildings require to be near a pylon, or else be enabled before disabling them. Or they will crash.
Second
You need to have something that reveals the unit, like a detector to make the unit cloak.
Remember that you can only disable 1 unit per trigger and i don't think shield battery will glow
Oh here's a disable/cloaking list i made
List![right][snapback]505376[/snapback][/right]
dude you dont need to power toss buildings to disable um... also you can disable more then 1 unit per trigger/location but yes, you do need detector to view it to cloak it.