Ring-11 Liquid Level Switch
The Ring-11 has obtained several industry certifications, including SIL2 / SIL3, CCC, CE, as well as certifications for Intrinsic Safety and Flameproof Enclosure explosion protection.
The Ring-11 Liquid Level Switch is a highly reliable and precise instrument designed for liquid level detection and control in a variety of applications. With a compact fork length of just 40mm, it is particularly suited for vessels, process tanks, storage tanks, pipelines, and other confined spaces. The switch operates based on the fork resonant principle, where the vibrating fork experiences a significant frequency decrease when it comes into contact with a liquid. This change in frequency is used to detect the presence of the liquid, and the fork’s resonant frequency is carefully calibrated to achieve high sensitivity. This allows the Ring-11 to detect fluids with densities as low as 0.5g/cm³, making it highly effective in a wide range of challenging applications.
For environments that require high resistance to corrosion, the Ring-11 offers an option with Hastelloy C-22, which provides excellent protection against aggressive chemicals such as HCl, H₂SO₄, H₂SO₃, as well as alkali liquids, syrup, medical fluids, and industrial wastewater. The Ring-11 is also ideal for applications involving pressurized liquefied gases, LNG, foaming liquids, high-viscosity substances, and environments subject to vibrations or mechanical disturbances. Additionally, the design incorporates a gas-tight leadthrough, ensuring the safe containment of high-pressure corrosive liquids and preventing accidental leakage.
The Ring-11 has obtained several industry certifications, including SIL2 / SIL3, CCC, CE, as well as certifications for Intrinsic Safety and Flameproof Enclosure explosion protection. It has been granted over 10 patents, including both invention patents and utility model patents , underscoring its innovative design and advanced technology.
With its robust performance and versatility, the Ring-11 Liquid Level Switch is an optimal solution for liquid level detection in demanding industrial environments.
Piezoelectric devices are used to drive vibration and detect changes. When the resonant vibration fork contacts the application medium, its vibration frequency decreases significantly. This reduction in frequency is reflected in the output signal from the piezoelectric detection device. An integrated circuit then analyzes this signal and generates a switch signal in response.
● 40mm Fork Length: Specially designed for pipelines and confined spaces, offering easy installation in tight environments.
● High Sensitivity: The fork’s harmonic resonant frequency is precisely pre-adjusted, enabling detection of media with a density as low as 0.5g/cm³.
● Strong Anti-Interference: Resistant to foam, bubbles, viscosity, oscillation, and other liquid characteristics, ensuring reliable performance in challenging conditions.
● Corrosion-Resistant Option: Hastelloy C-22 material withstands fluid corrosion and erosion in high-temperature applications, setting a benchmark in China’s technology.
● High Temperature Performance: The Ring-11 operates efficiently at process temperatures up to 250℃, making it ideal for high-temperature environments.
● Flexible Output Options: Choose from relay, two-wire, NAMUR, or transistor outputs for versatile integration.
● Certifications: Compliant with SIL2/SIL3 according to IEC 61508 standards, and certified for Intrinsic Safety and Explosion-Proof protection for use in hazardous areas.
● CE Certified: Meets European safety and environmental standards.
| Applicable liquid | Density | ≥0.5g/cm³ |
| Viscosity | 0.1～10000mPa.s ① | |
| Flow velocity | Max. 6m/s | |
| Probe data | Surface finish | Ra<0.5μm ② |
| Vibration frequency | ～1200Hz | |
| Fork length | 40mm | |
| Accuracy | Measurement error | ±1mm |
| Delay | 2mm | |
| Repeatability | 0.1mm | |
| Switching delay | When immersed | 0.5s |
| When laid bare | 1s | |
| Power supply | Relay | DPDT 20～253V AC/20～72V DC |
| Two-wire | 10～36V DC | |
| NAMUR | 8.2V DC | |
| Transistor | 6～48V DC | |
| Max. power consumption | 8VA(AC)；1.5W(DC) | |
| Output | Relay | 5A/253V AC/24V DC |
| Two-wire | 8mA/16mA，Alarm<2.3mA | |
| NAMUR | ≤1mA or ≥2.1mA， Fault ≤1mA | |
| Transistor | NPN/PNP | |
| Installation conditions | Process pressure | -1～64bar |
| Process temperature | Regular temperature: -50～150℃ | |
| High temperature: 50～250℃ | ||
| Ambient temperature | -40～70℃ | |
| Storage and transport temperature | -40～80℃ | |
| Overvoltage protection | Relay | Category III, class I |
| Two-wire | Category III, class II | |
| Certificates and approvals | SIL Qualification | SIL2 (HFT=0) / SIL3 (HFT=1) |
| China Compulsory Certification | CCC | |
| China Classification Society | CCS certificate for ships | |
| Explosion-Proof | Flameproof Enclosure: Ex d IIC T6～T1 Gb | |
| Intrinsic Safety: Ex ia IIC T6～T1 Ga | ||
| CE | LVD and EMC Certificates | |
| Ingress Protection | IP66/IP67 | |
| Materials | Housing | Aluminum alloy, , stainless steel |
| Ground terminal | 316L | |
| Thread connection | 316L | |
| Flange connection | 316L, 316L coated Enamel, ECTFE, PFA | |
| Fork | 316L, 316L coated Enamel, ECTFE, PFA | |
| Process seal | Klingersil C-4400 |
② Applicable: for Hygienic Ring-11 only.
● Liquefied Natural Gas (LNG): Effective for detecting LNG with a density of 0.56g/cm³ in transport pipelines, ensuring accurate level measurement in critical applications.
● Pump Protection Systems: Ideal for use in pipelines within pump protection systems, preventing damage and ensuring safe operation.
● Herbicides and Fungicides: Perfect for monitoring levels of herbicides and fungicides in insecticide manufacturing, ensuring precise control in chemical processing.
● Battery Electrolyte: Reliable for measuring battery electrolyte levels, critical in the production and maintenance of batteries.
● Food Industry: Suitable for food-grade liquids, such as syrups, oils, and beverages, where compliance with hygiene and safety standards is essential.
● High Temperature and High Pressure: Designed for high-temperature and high-pressure environments, with the ability to operate at process temperatures up to 250℃ and withstand challenging industrial conditions.
● Corrosive Liquids: With Hastelloy C-22 option, the Ring-11 can handle corrosive fluids, making it ideal for industries dealing with strong acids, alkalis, or industrial wastewater.
● Foaming and Bubbly Liquids: Performs reliably in applications with foaming or bubbling liquids, offering accurate level measurement even in such challenging conditions.
● High Viscosity Fluids: Suitable for thick, high-viscosity fluids, providing consistent and accurate detection even when liquids are dense or sticky.
