摘要 |
Apparatus, including an ultrasonic liquid level gauge and control system, includes a gauge configured to be coupled on the outside of a device, having a boiler or hot water tank, having liquid contained therein. The gauge is also configured to receive and contain a small part of the liquid of the device; and an ultrasonic transducing and signal processing arrangement configured to: reflect an ultrasonic pulse off a liquid surface of the small part of the liquid of the device contained in the gauge, and determine the level of liquid in the device based at least partly on a time of flight analysis related to the ultrasonic pulse reflected off the liquid surface of the small part of the liquid of the device contained in the gauge. |