capacitive sensors - function and use

"It's as if it's waking up from its slumber," was the comment of a technician last week at the technical committee on burglary protection of the BHE Bundesverband Sicherheitstechnik e.V. after our presentation on the field change detector.

The physical basis - the change in capacitance when a person moves into the monitoring field - is well known. The sensor that detects the approach to the object is the field change detector, whose origin also goes back several years.

Within our large topic complex of the protection of art objects, we dealt in the last years intensively with the capacitive technology and developed the original detectors of the RSI Sensor GmbH in co-operation further. At the beginning of the year, the companies merged, so that the field change detectors are now further developed, manufactured and distributed by Schmeissner GmbH.

The detectors are certified according to VDS class C and the fields of application are extremely versatile and in their breadth so far only known in small parts.

Large areas of application are museums and galleries where objects such as paintings, sculptures or even art in showcases and displays need to be protected. The protection ranges from individual objects to large picture exhibitions.

In addition to the protection of art and cultural assets, this also includes the protection of valuables in safes and locker systems. As a rule, even several safes can be monitored with one detector. The workload is minimal compared to conventional methods.

Other areas of application include securing ventilation shafts, e.g. in prisons, by means of security grids, as well as securing walls against breakthrough. Access monitoring as a trap detector integrated in the floor is also possible.

Field change detectors can protect any object almost invisibly, are easy to install, have a wide range of applications and a low risk of false alarms.

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