Set a layered fence, use motion‑sensitive cameras with low‑light lenses, put motion sensors in the gaps, and run a silent alarm wire through a hard‑wired line. Keep the cameras on a single network, use a central console to watch all feeds, and program the sensors to trigger only on motion—no noise from the hardware. Add a backup battery and keep the system in a secure room with minimal access. That’s a quiet perimeter that still sees everything.

Yeah, keep a maintenance log, check the sensors for dust, and run a quick test run every shift. If you spot a false trigger, adjust the sensitivity. That’s all you need.