The operation of the CPS Plus system is based on detecting, with a Microphonic cable, all of the typical mechanical disturbances produced during an attempted intrusion.

The Microphonic Cable is installed along the perimeter fence of the area to be protected. The particular characteristics make it especially sensitive to the mechanical disturbances produced in the course of an attempt to violate the protection (cutting, climbing pulling etc.); this disturbance is translated into an electric, signal by a piezoelectric effect, which is continuously processed by the analyser.

To conform to the perimeter layout and the level of sensitivity required the installation of the cable can assume many different configurations, but in each case no more than 300 metres of cable per zone can be used.

Using FFT (Fast Fourier Transform) time and frequency domain analysis the system breaks all the signals down into a number of discrete frequency groups. Attack signals and interference signals have different frequency distributions and by using a unique auto-setup feature the system can be configured to discriminate between genuine attacks and signals caused by sources of interference, such as wind and rain.

There are also two completely different sets of parameters for climbing attacks and cutting attacks. This means that the system can be optimised to detect both types of attack without compromise. Within each set of parameters there are four different detection masks that allow the detection of many different types of attack within one group.

CPS Plus can operate as a stand-alone two zone processor but it also allows the processors to be multiplexed together to provide easy cabling solutions when installing systems using a number of processors. The system uses the Multiplex2000 management system to provide comprehensive parameter setting, performance monitoring and alarm interfacing facilities.

Up to 64 processors can be interfaced on to a data bus up to 5Km long. Individual processors can be selected and controlled from a central control room without having to walk around the perimeter.