Title: Deployment of the inductance-based quasi digital sensor and instrument to monitor the metallic liquid level

Authors: Ramesh Sanga; M. Shivaramakrishna; G. Prabhakara Rao

Addresses: Security and Innovative Sensors Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102, India ' Security and Innovative Sensors Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102, India ' Security and Innovative Sensors Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102, India

Abstract: This paper proposes a simple method to develop an inductance type-level probe and device targeted towards the detection and monitoring of the metallic liquid level inside the process vessels of the pyroprocessing plant. An inductive quasi digital sensor-based approach is deployed to develop the level probe. A microcontroller-based instrument is designed and developed to monitor the metallic liquid level. Currently, there are no commercial sensors available in the market to detect the liquid metal level inside the tank for pyroprocessing plant. In this work, an inductance-capacitance (LC) type logic gate oscillator-based approach is detailed to measure the liquid level. The working principle, design concept, and results were discussed. A single coil inside a logic gate oscillator is used as a sensing element and the output frequency from the logic gate oscillator represents the level of the liquid metal. The sensor is mainly targeted to use at temperature 500°C and harsh radiation environment but currently developed sensor gives the feasibility of measuring the metallic liquid level at room temperature. Here, mercury is used as the liquid metal to test the sensor and instrument performance. The present design is suitable to measure the metallic liquid level in the range of 0 to 75 mm with a sensitivity of ~66 Hz/mm.

Keywords: quasi digital sensor; microcontroller; logic gate oscillator; inductor; molten metal; embedded system; mutual inductance; eddy current; transistor transistor logic; frequency.

DOI: 10.1504/IJIT.2021.123077

International Journal of Instrumentation Technology, 2021 Vol.3 No.1, pp.19 - 29

Received: 07 Jan 2021
Accepted: 26 Apr 2021
Published online: 26 May 2022 *

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