Logis-Tech Associates has launched a range of ultrasonic devices for listening to leaks in compressed air and vacuum installations as well as mechanical malfunctions/noise from movable parts.

by Hugo Gallagher, "Plant & Control Engineering", June 2002, issue 33, page 11.

The devices consist of a sensitive listening detector where a headphone or authorised hearing detector with loudspeakers can be connected. The system works by "listening" at a frequency band normally non-audible to humans(20kHz and up). Audible noises from the surrounding environment are filtered off. A key benefit of the sensor is that it can detect leaks in real time.

For mechanical malfunctions, the system consists of a detector with headphones or hearing protector where an electronic internal/external sensor can be connected. The sensor listens to mechanical noise and only picks up mechanical low frequency vibrations. Typical operations include bearings, pumps, motors, gears, and gearboxes. Conditions such as rubbing and lack of lubrication can also be detected.