System for monitoring a predetermined level of a fluid in a container

摘要

The liquid level monitoring device uses two identical ultrasonic transducers positioned on the outside of the container at the upper and lower limits and wired to excitation and processing electronics. A pulse of ultrasound at a predetermined frequency is transmitted through a diaphragm to the container wall. A plastic adaptor (21) is provided for attachment to a variety of containers with a sensor unit (20) which contains the transducer and can be attached to and detached from the adaptor.