An improvement in sensor devices, particularly but not exclusively underground laid ones, operating on the principle of capacitive state changes and generally useful to warn of heavy masses passing by, and related systems for operating the device

摘要

An improvement in sensor devices, particularly but not exclusively underground laid ones, generally for warning of heavy masses passing by and operating on the principle of capacitive state changes. The invention is also concerned with the capacitive arrangements provided to implement the device. This invention further relates to a means of implementing and installing the subject device.