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Fiber Defender FD322/IP

Category: Detection Systems

Sub Category: Barrier Mounted Detection

Fiber Defender FD322/IP


The FD322 is a fibre-optic intrusion detection system for fence perimeter security. It will detect if someone is climbing over, cutting through or crawling under the fence. 

This system has been assessed over a section of Anti-Intruder Weld Mesh Fence. Four runs of sensor cable were attached, one each to the 9th and 25th strand from the top and to the top and bottom barbed wire strands. The sensor cable is attached using metal twisted-wire cable ties every 250 mm.

The Anti-Intruder Weld Mesh Fence is built to BS 1722 Pt10 and is:

  • a rolled welded mesh;
  • apertures of 75 mm vertical x 25 mm horizontal and 3 mm strand thickness;
  • height of the fence fabric is 2.4 m;
  • topped with three strands of barbed wire;
  • overall height of 2.9 m to the top strand of barbed wire; and
  • each bay is 3 m in width and buried 300 mm into the ground.