Explainer
What Is a Perimeter Intrusion Detection System (PIDS)?
Updated 30 September 2026 · 7 min read
A perimeter intrusion detection system (PIDS) is a set of sensors that detects someone approaching, crossing or tampering with the boundary of a site, and raises an alarm so it can be checked and responded to. This guide explains the main types of PIDS, how temporary and permanent systems differ, and what it takes to keep one powered and online on remote sites.
What a perimeter intrusion detection system does
A PIDS watches the edge of a site rather than the buildings inside it. The aim is to detect an intruder as early as possible — at the fence line, not at the door — which gives more time for a camera to confirm what is happening and for a response to arrive.
Every PIDS has the same basic parts: detectors along the perimeter, a controller or panel that processes their signals, a way of sending alarms to a monitoring centre or security team, and a power supply. On most sites the PIDS works alongside CCTV, so an alarm from a zone can be checked against a camera view before anyone is sent.
Types of perimeter intrusion detection
Different detection technologies suit different boundaries, budgets and environments. Many sites combine more than one.
| Type | How it detects | Typical use |
|---|---|---|
| Fence-mounted | Sensors or cable on the fence pick up cutting, climbing and lifting | Existing fences on construction, utility and industrial sites |
| Buried | Pressure or cable sensors in the ground detect footsteps and vehicles | High-security or covert perimeters |
| Microwave | A beam between two units detects anything crossing it | Open ground and gateways |
| Infrared beam | Invisible beams between posts are broken by an intruder | Straight fence lines and entrances |
| Radar | Scans an area and tracks moving objects | Large open sites such as solar farms |
| Video analytics | Software analyses camera images for people and vehicles | Sites with CCTV coverage of the boundary |
Temporary vs permanent PIDS
Permanent systems protect sites such as substations, prisons, airports, data centres and utility plants. They are designed in from the start, run on mains power and connect to fixed networks.
Temporary PIDS protect sites for weeks or months: construction projects, solar farm builds, infrastructure works, events and void properties. They are usually deployed from kits that move from job to job, often with battery-powered detectors, beam towers or tower-mounted cameras, and communicate over the mobile network. That flexibility brings its own challenges: power, coverage and physical robustness change with every site.
Powering a PIDS off-grid
Temporary and remote perimeters rarely have mains power along the boundary. Detectors, controllers and communications run from batteries, charged by solar panels, fuel cells or a nearby generator.
This is where most problems start. A battery bank sized for summer can run short in December, a shaded solar panel can stop charging, and a fuel cell can run out of cartridges. When the power fails, the perimeter goes quiet — and a quiet perimeter looks the same as a secure one until someone checks.
- Size batteries for the worst month, not the average
- Use a backup charging source such as a fuel cell where solar is marginal
- Measure state of charge, not just voltage
- Get an alert well before the battery is flat
Why false alarms and call-outs happen
Nuisance alarms from weather, wildlife and vegetation are a well-known PIDS problem, and are handled by the detection system's settings and by checking cameras. But on temporary sites a large share of engineer visits have nothing to do with detection at all: flat batteries, lost signal, a knocked beam tower or a controller that needs a restart.
Telling these apart from the office is the key to cutting call-outs. If you know the system is powered, charging and connected, a fault is more likely to be real; if the battery has been falling for two days, you know what the engineer needs to take.
Monitoring PIDS health remotely
Remote health monitoring sits alongside the PIDS rather than replacing it. The detection system and the monitoring centre keep doing their jobs; health monitoring answers the supporting questions: is the system powered, how long will the battery last, is it connected, and has anything been moved or tilted.
TrackSyte does this with the Neo 2 gateway on each installation, reading power and battery data from Victron equipment, smart lithium batteries and EFOY fuel cells, discrete signals over GPIO, controllers over RS485 / Modbus, and Ajax security systems where used. Each installation's location comes from full-constellation GNSS, and everything appears in one portal with alerts by email, webhook or Slack.
FAQs
What does PIDS stand for?
Perimeter intrusion detection system: sensors and a controller that detect someone approaching, crossing or tampering with a site boundary and raise an alarm.
What is the difference between PID and PIDS?
They are used interchangeably. PID usually means perimeter intrusion detection, and PIDS refers to the complete perimeter intrusion detection system.
Which type of perimeter intrusion detection is best?
It depends on the boundary. Fence-mounted sensors suit existing fences, beams and microwave suit straight runs and gateways, radar suits large open sites, and video analytics suits sites with good camera coverage. Many sites combine types.
Can a temporary PIDS run without mains power?
Yes. Temporary systems typically run on batteries charged by solar, fuel cells or a generator. Monitoring battery state of charge and charging is essential to keep them working through winter.
Does remote monitoring verify intrusion alarms?
No. Alarm verification stays with the detection system, cameras and monitoring centre. Health monitoring covers power, battery, connectivity, tilt and location so faults can be diagnosed before an engineer is sent.
Keep your perimeter powered and online
See how TrackSyte shows power, battery, connectivity, tilt and location for every PIDS installation in one portal.