Orbital defence grid
From Tardis Wiki, the free Doctor Who reference
Orbital defence grid was an orbital array that protected planet Mechanus.
It sustained minor damage when the Daleks led by the Emperor of the Restoration arrived on the planet. Dalek Prime Strategist commanded to repair it immediately, but Mechanoid 2150 noticed that something was draining energy from the defence grid. Despite the efforts of them and the Strategist the energy was drained completely, leaving the Mechonoids defenceless. (WC: Planet of the Mechanoids)
