warmth insulated pipe system with means for detecting of moisture into the insulation

摘要

A heat insulated pipe system, especially a subterranean district heating pipe system, comprises electric wires incorporated in the heat insulating material and local detectors 8 for detecting an increase of electric conductivity between the wires due to moisture intrusion into the material. Clock pulses (e.g. cycles of power A.C.) drive individual counters 24 at the detectors, which are sequentially counted full for temporarily switching 22 the detector outputs to a common signal wire going to a central station, such that any moisture responding detector is readily identified by the associated counter step of a central counter 28. IMAGE