High precision intelligent apparatus driven by a step motor for measuring liquid level

This paper presents a steel rope float type apparatus driven by a step motor for measuring liquid level. The apparatus consists of a tank top gauge, a pulse power supply, a STD industrial computer (Z80CPU) and a multiplexer. This apparatus has the features of very simple mechanic construction of the top gauge, uncomplicated circuit, highly accurate measurement, almost no influence by surrounding temperature variation, low cost, convenient operation, and easy maintenance. It can be not only used in making a long distance tour of tank group measurements but also can be plugged into a distributed control system (DCS) so as to directly provide data.<
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