Level gauge problem

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Working principle: It utilizes radio frequency admittance technology and consists of two parts: an electronic circuit and a probe. The electronic circuit includes a high-frequency oscillator, a detection circuit, and an output circuit. The probe is made up of a detection electrode and a protective cover; both of these components are insulated from each other as well as from the grounded container. A stable radio frequency voltage is provided by the high-frequency oscillator and transmitted to the detection electrode. When material comes into contact with the detection electrode, an unbalanced voltage is generated, which, after being processed by a demodulator and amplifier, triggers the relay to operate. Installation requirements: 1) Avoid excessive torque between the housing and the probe rod ； 2) The end of the probe should be at least 100 mm away from the container; 3) The probe should be installed far away from the feed inlet; 4) If installed in a non-metallic container, it must have proper grounding ； If installed in a reinforced concrete silo, the instrument’s grounding terminal should be connected to the rebar inside it ； 5) In cases where foreign objects fall or materials impact the sensor, a protective cover should be installed. This cover can be made of circular or semi-circular steel pipes or angle iron, and it must have sufficient strength (when the distance between the protective cover and the probe is less than 100 mm, the sensitivity needs to be adjusted again); 6) When measuring the level of liquid substances, the density of the material should be greater than 240 kg/m3 ； 7) When the temperature of the object being tested exceeds 100°C, it is recommended to use a split-type design for installation ； 8) When installed horizontally, the outlet of the housing should be at the bottom. The correct installation location of a level gauge is often determined by the position of the container opening at the installation point. When installed in threaded ports or flanged connections, make sure that the connection does not extend beyond the first insulating layer of the sensing probe. During installation, make sure that the insulation layer of the sensing probe is not cut or scratched.