The GD5000 analyser, combined with Alpha Sensor, is a stand alone perimeter intruder detection device. It exploits the precision Alpha Sensor technology by processing the analogue signal generated by an intrusion attempt on the perimeter fence For use with the Defensor system, it is designed to pick up vibrations as soon as any contact is made with the fence. A security system which incorporates Defensor will alarm as soon as an attack starts. During the time taken to breach the fence, the area of attack can be located, security staff mobilised and CCTV, lights and sirens activated. This means that the control of the situation stays with the security service and the attack can often be prevented.