a test platform that doesn't work.
Of course!
but if we say that the cables is for data. then the power that gun need, it will get from the ship's engine room. The ship has six gas turbines. and two of them have been disconnected because she no longer needs to be fast when she's a testing platform. so the two gas turbines could be a ...
Also, we can say that she got the laser mounted on an old cannon towers, that would drop the cost of building a brand new one. Use an old one and locks it firmly in a specific position.
If these people in the odd lab trying to create a laser in a turret which can be turned!
one time or another, someone will make a laser that can be used in a turret which can be turned around. But the question is "when!" 50, 100, 5,000,000 years from now!