Radio frequency capacitive liquid level gauge is suitable for measuring the liquid level (material level) of pressurized conductive and non-conductive liquids (solids) in pressurized containers. The product is powered by two-wire system, which outputs 4-20mA and superimposes Hart digital signal. At the same time, ufb RF capacitive liquid level gauge is powered by two-wire system, which outputs 4-20mA and superimposes Hart digital signal. At the same time, it can display the liquid level locally. Using the two-wire isolation and conversion technology of sensor signal, the 4-20mA isolation signal output is completely isolated from the field analog signal, ground wire, etc. The liquid level can be displayed locally. Using the two-wire isolation and conversion technology of sensor signal, the 4-20mA isolation signal output is completely isolated from the field analog signal, ground wire, etc. Ordinary ufb capacitive level transmitter belongs to capacitive liquid level detection instrument, which can convert the changes of various liquid level parameters into standard current signals and transmit them to the operation room for centralized display, alarm or automatic control of secondary instruments or computer devices.
Radio frequency capacitive liquid level gauge can convert the changes of various liquid level parameters into standard current signals and transmit them to the operation room for centralized display, alarm or automatic control by secondary instruments or computer devices. Combined with the user’s specific process conditions, equipment structure and use requirements, through the flexible combination of the material, structure and installation mode of the liquid level gauge, it can be applied to the continuous detection of liquid level, material level or material level under special conditions such as high pressure, high temperature, strong corrosion, easy crystallization, anti blocking, anti freezing and solid powder, granular materials, and can be widely used in the detection and control of various industrial processes.
The detection principle of the liquid level gauge is capacitance conversion type. Its principle: two parallel plates, which are parallel to each other and closely separated from each other, form a capacitor. The capacitance of the capacitor changes with the change of liquid level. The change of capacitance corresponding to the change of liquid level is converted into a standard current signal through the transmission circuit and output to the secondary meter to display the corresponding liquid level height.
Basic calculation formula Δ C=(0.885· ε·Δ S)/d
In the above formula, 0.885 is the calculation constant, ε The dielectric constant of the measured medium, △ s is deep into the surface of the medium and the product, D is the distance between the two poles.
In the above formula, the invariant is ignored, and the conversion formula can be simplified as Δ C= Δ S=> Δ C=∏R2=> Δ C= Δ H means that only Δ H. That is, the liquid level changes up and down, and the amount of change has nothing to do with temperature and pressure. The capacitive liquid level structure is composed of transmission circuit, structural connector, probe rod, etc.
Single electrode is suitable for: the equipment of the measured medium is a metal container, and the medium with good conductivity.
Cable type double electrode is applicable to: the equipment of the measured medium is a non-metallic container, the medium with good conductivity or the electrode with a length greater than 3m.
Threaded connection: m27*2, m20*1.5, 3/4 “, etc;
Flange connection: flange installation: dn25-dn100hg20592
High pressure flange: dn15n pn32 (three hole flange, lens pad).
Features of RF capacitive liquid level gauge:
Liquid level measurement of conductive medium in pressurized vessels: various acids, bases and salts: 98% H2SO4 concentrated H3PO4 concentrated HCl, NaOH, etc;
Liquid level measurement of non-conductive liquid: oil, solvent CO2, etc;
Solid: fly ash, cement;
High pressure vessel: liquid ammonia: working pressure: 10MPa;
Working medium temperature: -70-200 ℃ (PTFE electrode);
Local LCD display + transmission +hart digital data signal;
It can adjust zero point, full scale, damping time, data recovery and other functions with three buttons on site; Completely replace the manual operator;
Liquid level detection is basically not affected by changes in process conditions. The buoyancy type, differential pressure type and isotope type liquid level gauges are all related to the importance of the medium in the detection. The change of the gravity of the gas-liquid phase medium will cause additional errors in the detection results;
Wide application range: it is specially customized according to the specific characteristics of the test object, which can adapt to liquid level detection under a variety of harsh conditions;
Light installation: the self weight of a high-pressure liquid level gauge working under 32Mpa is less than two kilograms, which is one tenth of the weight of the high-pressure pontoon liquid level gauge.
Technical indicators of RF capacitive liquid level gauge:
Measurement range: rod type 0 ~ 3500mm, cable type 2 ~ 20m, optional;
Accuracy: ± 0.25% F.S, ± 0.5% F.S; (range within 1m ± 5mm) when the measured medium is crystallization, scaling or high viscosity, it will have a certain impact on the measurement accuracy;
Working pressure: 0–10mpa; Working medium temperature: -70-200 ℃ (PTFE electrode);
Working voltage: 24VDC output signal: 4 ~ 20mA superimposed Hart digital signal, load resistance: 0~600 Ω;
Applicable medium: any medium without corrosion to polytetrafluoroethylene;
When supporting the secondary meter, two-wire power supply is attached to the secondary meter;
Mounting thread: below 22Mpa, pressure pad type, M33 × 2； Pressure lens type below 32Mpa. M33 × 2 or M24 × 2;
Materials of structural connectors: chrome plated parts, 1 cil8ni9ti, 316L, mo2ti, etc.
ф 8mm single electrode: 0-200—2000mm, ф 12mm single electrode: 0-200—3000mm
Coaxial double electrode ф 22mm（ ф 19mm）/ ф 8mm：0—300—3000mm
ф 3.6m cable type single electrode: 0-2—20m, 4.3*2.5 cable type double electrode: 0-2—20m
Post time: 20-07-22