| 摘要 |
<p>The invention comprises a surface switch for determining the surface level of an explosive liquid stored in a container (15), for instance. Information about changes in the surface level is transmitted from the surface switch sensor (10) through an optic fibre cable (11) to the receiver (14) of a control unit (12). The surface level information correlates with the intensity of a returning light beam is controlled by means of a glass ball (6).</p> |
