摘要 |
<p>The device has a detection cable (10c) comprising an element i.e. central electric wire (1), and an elongated electrically conducting element formed of electric wire, metal layer and another electric wire (2c), where the elements are separated by an extruded layer (3) of polymer material. A measurement apparatus e.g. megohmmeter, measures electrical resistance between the elements of the cable. The material is non-soluble and sensitive to moisture. The central electric wire is surrounded by the layer of polymer material, and the electric wire is wound around the layer of polymer material.</p> |