| 摘要 |
Device for preventing a biological growth on a surface immersed in water, and this device comprises a sound generator to propagate ultrasound, and this sound generator is formed by a transducer and an electrical or electronic controller for this transducer that is connected to an electricity supply that can be connected to an electrical power source, characterised in that the device is equipped with a meter for measuring the duration of the power failures of the supply of the sound generator. |
