MICROWAVE-BASED POINT LIQUID LEVEL MONITORING SYSTEM

摘要

A point liquid level monitoring system includes a sensor removeably mounted to a liquid level device. The sensor is designed to direct a microwave signal from a transmitter through a window in the liquid level device. In one embodiment, the microwave signal is reflected off a surface in the device opposite the window and collected by a receiver. In another embodiment, the microwave signal is collected by a receiver mounted onto a second window opposite the first window through which the microwave signal is transmitted. When liquid is present in the liquid level device at or above the level of the transmitter and receiver, the microwave signal is attenuated as it passes through the liquid. Sensor electronics compare the received signal to a predetermined threshold level and provide an output indicating the presence or absence of liquid at the transmitter/receiver level. The sensor can be easily installed or removed from the liquid level device without draining, depressurizing, or otherwise disturbing the operation of the device or attached fluid systems and, when installed, does not obstruct visually reading liquid levels in the device.