| 摘要 |
The invention relates to a device for sensing and indicating the state of a medium in a conduit. The device comprises a sensor means (10) for sensing the value of a parameter of the medium in the conduit (8), and an indicator means (13) which is coupled to the sensor means and is intended to provide an indication which is dependent on said sensed value. According to the invention, the sensor means (10) is coupled into the conduit (8) and is provided with a channel which, when coupled, is a portion of the conduit. The sensor means (10) has two electrodes insulated from each other, which extend into the channel. The indicator means is provided with, or is coupled to, a current source for applying a voltage between the electrodes of the sensor means (10) and is arranged to provide an optical and/or acoustic signal when the resistance of the medium lies beyond a predetermined threshold value. |
