[Taqwus]

You mean the Long Range Scanners, right?

There's also a range limitation on them (five squares for a LRS III, if memory serves).

If the target is known (it can be cloaked, as long as you've got good-enough sensors in the same system), within range, not using scanner jammers (including the armor which jams it -- either stealth or scattering, don't recall which one), and it's a ship (not a planet!) -- just select it. IOW, it doesn't go through any "use component" option; it's always-on.